HomeMy WebLinkAboutDrainage Reports - 08/08/2013I
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August 5, 2013
C'tty of Ft. Collinsm:o;;:ns
Approved By. .
Date j>-)j.3 · ·
FINAL DRAINAGE AND
EROSION CONTROL REPORT
RIVER DISTRICT BLOCK ONE MIXED USE
, -' This O~inage Report is consciously provided as a PDF. . __
Please consider the envifonmei1t before printing this document in its entirety.
When a hard copy is absolutely necessary, we recommeild.-d!>u,~_i_e.-iict_~ printing.
Fort Collins, Colorado
Prepared for:
Encompass Technologies
324 Jefferson Street
Fort Collins, CO 80524
Prepared by:
NORTHERN
ENGINEERING
200 South College Avenue, Suite 10
Fort Collins, Colorado 80524
Phone: 970.221.4158 Fax, 970.221.4159
www.riorthernengineering.com
Project Number: 685,002
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NORTHERN
ENGINEERING
August 5, 2013
City of Fort Collins
Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
ADDRESS,
200 S. College Ave. Suile 10
Fort Collins. CO 80524
RE: Final Drainage and Erosion Control Report for
RIVER DISTRICT BLOCK ONE MIXED USE
Dear Staff:
PHONE, 970.221.4 I 58 WEBSITE,
FAX, 970.221.4159 www.nor thernengineer i ng.corn
Northern Engineering is pleased to submit Final Drainage and Erosion Control Report for your
review. This report accompanies the Project Development Plan submittal for the proposed River
District Block One Mixed Use development.
This report has been prepared in accordance to Fort Collins Stormwater Criteria Manual (FCSCM),
and serves to document the stormwater impacts associated with the proposed project. We
understand that review by the City is to assure general compliance with standardized criteria
contained in the FCSCM.
If you should have any questions as you review this report, please feel free to contact us.
Sincerely,
NORTHERN ENGINEERING SERVICES, INC.
tL{L
Aaron Cvar, PE
Project Engineer
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N S I NORTHERN
...5 I [NGINf.ERING
I River District Block One Mixed Use
TABLE OF CONTENTS
I. GENERAL LOCATION AND DESCRIPTION ................................................................... 1
A. Location ............................................................................................................................................. l
B. Description of Property ..................................................................................................................... 2
C. Floodplain .......................................................................................................................................... 3
11. DRAINAGE BASINS AND SUB-BASINS ....................................................................... 5
A. Major Basin Description .................................................................................................................... 5
111. DRAINAGE DESIGN CRITERIA ................................................................................... 5
A. Regulations ........................................................................................................................................ 5
B. Four Step Process .............................................................................................................................. 5
C. Development Criteria Reference and Constraints ............................................................................ 6
D. Hydrological Criteria ......................................................................................................................... 6
E. Hydraulic Criteria .............................................................................................................................. 6
F. Floodplain Regulations Compliance .................................................................................................. 7
G. Modifications of Criteria ................................................................................................................... 7
IV. DRAINAGE FACILITY DESIGN .................................................................................... 7
A. General Concept ............................................................................................................................... 7
B. Specific Details .................................................................................................................................. 8
V. CONCLUSIONS ........................................................................................................ 9
A. Compliance with Standards .............................................................................................................. 9
B. Drainage Concept .............................................................................................................................. 9
References ....................................................................................................................... 1 O
APPENDICES:
APPENDIX A
APPENDIX B
B.l
APPENDIX C
APPENDIX D
APPENDIX E
APPENDIX F
APPENDIX G
-Hydrologic Computations
-Hydraulic Computations
-Storm Sewers
-Water Quality Design Computations
-Stormwater Management Plan (Erosion Control Report)
-FEMA FIRMette
-EPA SWMM Analysis
-Standard Operating Procedures (SOPs)
Final Drainage and Erosion Control Report
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N-=;S NORTHERN
---[NGINEU11NG
River District Block One Mixed Use
LIST OF TABLES AND FIGURES:
Figure 1 -Aerial Photograph ................................................................................................ 2
Figure 2-Proposed Site Plan ................................................................................................ 3
Figure 3 -Existing Floodplains ............................................................................................. 4
Table 1 -Water Quality Pond Summary ................................................................................. 9
MAP POCKET:
Drainage Exhibits
Final Drainage and Erosion Control Report
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N ·;c,, ; NORTHERN
_5 fNGINf(RING River District Block One Mixed Use
I. GENERAL LOCATION AND DESCRIPTION
A. Location
1. Vicinity Map
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2. The project site is located in the northwest quarter of Section 12, Township 7 North,
Range 69 West of the 6 th Principal Meridian, City of Fort Collins, County of Larimer,
State of Colorado.
3. The project site is located on the east side of Linden Street, and just north of Willow
Street. The Cache La Poudre River runs just to the north of the project site.
4. The project site lies within the Downtown River District study area (Ayres, 2012), and
is located within Basin 115. This basin has a master planned outfall directly to the
Cache La Poudre river, which runs just north of the project site. However, based on
direction by the City, a new outfall to the river is not desired. The site will outfall to
the existing Linden Street storm system. Due to the project site proximity to the river,
no detention is required for onsite runoff.
5. Downtown development exists to the south and west of the site.
Final Drainage and Erosion Control Report 1
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N e=' II NORTHERN _5 ENGINEERING
I River District Block One Mixed Use
south bank of the Cache La Poudre River related to the proposed stabilization
measures being undertaken with this project. Upon completion of construction, a
Letter of Map Revision (LOMR) will be submitted to FEMA, based on as-constructed
conditions.
II. DRAINAGE BASINS AND SUB-BASINS
A. Major Basin Description
1. The project site is located within the Downtown River District study area (Ayres,
2012), and is located within Basin 115.
B. Sub-Basin Description
2. The subject property historically drains overland towards the Cache La Poudre River,
which runs northeast of the site. A more detailed description of the project drainage
patterns follows in Section IV.A.4., below.
3. Developed areas to the southwest of the site historically drain through the project site.
These off-site drainage flows and patterns will be maintained and accounted for with
the proposed development.
Ill. DRAINAGE DESIGN CRITERIA
A. Regulations
There are no optional provisions outside of the FCSCM proposed with the proposed
project.
B. Four Step Process
The overall stormwater management strategy employed with the proposed project utilizes
the "Four Step Process" to minimize adverse impacts of urbanization on receiving waters.
The following is a description of how the proposed development has incorporated each
step.
Step 1 -Employ Runoff Reduction Practices
Several techniques have been utilized with the proposed development to facilitate the
reduction of runoff peaks, volumes, and pollutant loads as the site is developed from the
current use as athletic facilities by implementing multiple Low Impact Development (LID)
strategies including:
Nil Conserving existing amenities in the site including the existing vegetated areas.
Nil Providing vegetated open areas throughout the site to reduce the overall impervious
area and to minimize directly connected impervious areas (MDCIA).
No Routing flows, to the extent feasible, through vegetated swales to increase time of
concentration, promote infiltration and provide initial water quality.
Step 2 -Implement BMPs That Provide a Water Quality Capture Volume (WQCV) with
Slow Release
The efforts taken in Step 1 will facilitate the reduction of runoff; however, urban
development of this intensity will still generate stormwater runoff that will require
additional BMPs and water quality. All stormwater runoff from the site will ultimately be
routed to the northeast corner of the site, where it is intercepted and treated in the main
water quality pond prior to exiting the site.
Final Drainage and Erosion Control Report 5
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C.
NORTHERN
ENGINEERING River District Block One Mixed Use
Step 3 -Stabilize Drainageways
There are no major drainageways within the subject property. While this step may not
seem applicable to proposed development, the project indirectly helps achieve stabilized
drainageways nonetheless. By providing water quality where none previously existed,
sediment with erosion potential is removed from the downstream drainageway systems
and Cache La Poudre River. Furthermore, this project will pay one-time stormwater·
development fees, as well as ongoing monthly stormwater utility fees, both of which help
achieve City-wide drainageway stability.
Step 4 -Implement Site Specific and Other Source Control BMPs.
The proposed project will require the need for site specific source controls including:
ND Several localized trash enclosures throughout the site for the disposal of waste
products.
Development Criteria Reference and Constraints
The subject property is essentially an "in-fill" development project as the property is
surrounded by currently developed properties. As such, several constraints have been
identified during the course of this analysis that will impact the proposed drainage
system including:
Nil Existing elevations along the west and south property lines will be maintained.
Nm As previously mentioned, overall drainage patterns of the existing site will be
maintained.
Nil Elevations of existing downstream facilities that the subject property will release to
will be maintained.
D. Hydrological Criteria
1. The City of Fort Collins Rainfall Intensity-Duration-Frequency Curves, as depicted in
Figure RA-16 of the FCSCM, serve as the source for all hydrologic computations
associated with the proposed development. Tabulated data contained in Table RA-7
has been utilized for Rational Method runoff calculations.
2. The Rational Method has been employed to compute stormwater runoff utilizing
coefficients contained in Tables R0-11 and R0-12 of the FCSCM.
3. Three separate design storms have been utilized to address distinct drainage
scenarios. A fourth design storm has also been computed for comparison purposes.
The first design storm considered is the 80th percentile rain event, which has been
employed to design the project's water quality features. The second event analyzed is
the "Minor," or "Initial" Storm, which has a 2-year recurrence interval. The third
event considered is the "Major Storm," which has a 100-year recurrence interval.
The fourth storm computed, for comparison purposes only, is the 10-year event.
4. No other assumptions or calculation methods have been used with this development
that are not referenced by current City of Fort Collins criteria.
E. Hydraulic Criteria
1. As previously noted, the subject property maintains historic drainage patterns.
2. All drainage facilities proposed with the project are designed in accordance with
criteria outlined in the FCSCM and/or the Urban Drainage and Flood Control District
(UDFCD) Urban Storm Drainage Criteria Manual.
3. As stated above the subject property is located in a FEMA regulatory floodplain.
Final Drainage and Erosion Control Report 6
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N e"' : NORTHERN _5. fNGlt<EERING River District Block One Mixed Use
IV.
4. The proposed project does not propose to modify any natural drainageways.
F. Floodplain Regulations Compliance
1. As previously mentioned, all structures are located outside of the Cache La Poudre
100-year floodplain, and thus the structures are not subject to any floodplain
regulations. However, extra care has been taken to ensure that neither existing nor
proposed structures will suffer damage during the 100-year storm as a result of the
proposed development.
2. Stabilization measures are being taken along the south bank of the Cache La Poudre
River. All stabilization design work is being conducted by Flywater Consultants.
Please refer to Flywater Consultants' design report for further discussion of bank
stabilization and related floodplain issues.
3. Critical facilities are prohibited within the 100-year and 500-year floodplain.
4. A floodplain use permit must be obtained prior to any work to be done within the
floodplain prior to construction. A no-rise certification must be completed for any
work to be done within the floodway prior to construction.
5. No floatable items are proposed within the floodway. Any floatable items within the
floodway must be anchored to prevent flotation.
6. A FEMA Conditional Letter of Map Revision (CLOMR) has been submitted and is
currently under FEMA review. This CLOMR is based on proposed changes to the
south bank ofJhe Cache La Poudre River related to the proposed stabilization
measures being undertaken with this project. Upon completion of construction, a
Letter of Map Revision (LOMR) will be submitted to FEMA, based on as-constructed
conditions.
G. Modifications of Criteria
1. The proposed development is not requesting any modifications to criteria at this time.
DRAINAGE FACILITY DESIGN
A. General Concept
1. The main objectives of the project drainage design are to maintain existing drainage
patterns, ensure no adverse impacts to any adjacent properties, and to maintain the
drainage concepts as outlined in the Downtown River District study (Ayres, 2012).
2. Developed areas to the southwest of the site historically drain through the project site.
These off-site drainage flows and patterns will be maintained and accounted for with
the proposed development.
3. A list of tables and figures used within this report can be found in the Table of
Contents at the front of the document. The tables and figures are located within the
sections to which the content best applies.
4. The drainage patterns anticipated for proposed drainage basins are described below.
Basin 1
Basin 1 consists of landscaped and concrete areas to the north and west of the
proposed building. The basin drains to the adjacent Linden Street.
Final Drainage and Erosion Control Report 7
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N ·s : NORTHERN
..5 ' f.NGINfERING River District Block One Mixed Use
Basin 2
Basin 2 consists entirely of the rooftop of the proposed building. The basin drains into
an existing "Bay Saver" water quality treatment unit, which outfalls to the existing
Linden Street storm sewer.
Basin 3
Basin 3 consists of landscaped and concrete areas to the north of the proposed
building. The basin drains as sheet flow into the Poudre River.
Basin 4
Basin 4 consists mainly of the proposed parking area. The basin drains into the
proposed water quality pond to be constructed with the development.
Basin 5
Basin 5 consists of landscaped areas to the southeast of the proposed building. The
basin drains as sheet flow into the Poudre River.
Basin OSl
Basin OSl consists of developed areas to the south of the project site. Runoff from
this basin will follow existing drainage patterns, as stormwater from this basin will be
directed via sheet flow to curb and gutter which will direct flows to Linden Street. An
area inlet and storm line (Storm Line B) have been added to capture minor (2-year)
flows prior to entry into Linden Street. Major (1O0-year) flows will sheet flow into
Linden Street, consistent with historic drainage patterns.
Basin OS2
Basin OS2 consists of developed areas to the south of the project site. Runoff from
this basin will follow existing drainage patterns, as stormwater from this basin will be
directed via sheet flow through the site and into the Poudre River.
Basin OS3
Basin OS3 consists of developed areas to the south of the project site. Runoff from
this basin will follow existing drainage patterns, as stormwater from this basin will be
directed via sheet flow through the site and into the Poudre River.
A full-size copy of the Drainage Exhibit can be found in the Map Pocket at the end of
this report.
B. Specific Details
1. Water quality treatment is being provided for the proposed development in the
form of extended detention as previously described. Standard Operating
Procedures (SOPs) are provided in Appendix G. A final copy of the approved
SOP manual shall be provided to City and must be maintained on-site by the
entity responsible for the facility maintenance. Annual reports must also be
prepared and submitted to the City discussing the results of the maintenance
program (i.e. inspection dates, inspection frequency, volume loss due to
sedimentation, corrective actions taken, etc.).
2. Table 1, below, summarizes the water quality information for the proposed water
quality pond.
Final Drainage and Erosion Control Report 8
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V.
NORTHERN
f.NGIIHf.RING River District Block One Mixed Use
Table 1 -Water Quality Pond Summary
Pond
Water Quality Water Quality Spillway Top of Pond
Capture Volume WSEL Elevation Elevation
{AC-FT) (FT) (FT) (FT)
0.012 4952.30 4953.50 4953.50
3. Proper maintenance of the drainage facilities designed with the proposed
development is a critical component of their ongoing performance and effectiveness.
The water quality pond may be easily accessed by maintenance staff via the gentle
slope provided to the bottom of the pond from the south side.
4. The drainage features associated with the proposed project are all private facilities,
located on private property, with the exception of the pond outfall. An easement will
be dedicated for the portion of the pond outfall that lies within City property.
5. The proposed outfall pipe will outfall to the existing storm line in Linden Street, which
drains north to the Cache La Poudre River.
CONCLUSIONS
A. Compliance with Standards
1. The drainage design proposed with the proposed project complies with the City of Fort
Collins' Stormwater Criteria Manual.
2. The drainage design proposed with this project complies with the Downtown River
District Final Design Report (Ayres, 2012).
3. There are no regulatory floodplains within the proposed development.
4. The drainage plan and stormwater management measures proposed with the
proposed development are compliant with all applicable State and Federal regulations
governing stormwater discharge.
5. The proposed development is in compliance with Chapter 10 of City Code.
B. Drainage Concept
1. The drainage design proposed with this project will effectively limit any potential
damage associated with its stormwater runoff by providing an extended detention
water quality pond.
2. The drainage concept for the proposed development is consistent with the Downtown
River District Final Design Report (Ayres, 2012).
Final Drainage and Erosion Control Report 9
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N = I NORTHERN _s I ENGINEERING River District Block One Mixed Use
References
1. City of Fort Collins Landscape Design Guidelines for Stormwater and Detention Facilities,
November 5, 2009, SHA Design, Inc. with City of Fort Collins Utility Services.
2. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, as adopted by Ordinance No.
17 4, 2011, and referenced in Section 26-500 (c) of the City of Fort Collins Municipal Code.
3. Larimer County Urban Area Street Standards, Adopted January 2, 2001, Repealed and
Reenacted, Effective October 1, 2002, Repealed and Reenacted, Effective April 1, 2007.
4. Soils Resource Report for Larimer County Area. Colorado, Natural Resources Conservation
Service. United States Department of Agriculture.
5. Urban Storm Drainage Criteria Manual. Volumes 1-3. Urban Drainage and Flood Control
District. Wright-McLaughlin Engineers, Denver. Colorado. Revised April 2008.
6. Downtown River District Final Design Report, February 2012, Ayres Associates.
7. Subsurface Exploration Report. 418 Linden Street. October 25. 2011. Earth Engineering
Consultants. Inc.
Final Drainage and Erosion Control Report
- - -- - -- ------ - -- -- -DEVELOPED RUNOFF COMPUTATIONS ~-,_, Rational Method Eguation: Ra.Tl:ONAL M&'tBCD nt£QllDICr AD~'Dmn' i'.1L"1'0RS Project: 685-002 Q = C 1(c)(i)(A) St:o=a lletuza hrlod ~cy i'&Qbn Calculations By: ATC (X'!!;:!') C. Date: April 15, 2013 From Section 3.2. l of the CFCSDDC 2 to 10 1.00 ll to 25 1.10 26 to SO 1.20 51 to 100 1.25 Rainfall Intensity: Note: The p~oduct ot C times Ci sha.ll not exceed. 1.00 Rainfall Intensity taken from the City of Fort Collins Storm Drainage Design Criteria (CFCSDDC), Figure 3.1 Design Area, A 2-yr 10-yr 100-yr Intensity, Intensity, Intensity, Flow, Flow, Flow, Point Basin(s) (acres) T, T, T, c, C10 C100 i, i10 iioo G, G10 G100 (min) (min) (min) (in/hr) (in/hr) (in/hr) (cfs) (cfs) (cfs) I 1 0.05 5 5 5 0.95 0.95 1.00 2.85 4.87 9.95 0.1 0.2 0.5 2 2 0.30 5 5 5 0.95 0.95 1.00 2.85 4.87 9.95 0.8 1.4 3.0 3 3 0.02 5 5 5 0.34 0.34 0.42 2.85 4.87 9.95 0.0 0.0 0.1 4 4 0.59 6 6 5 0.62 0.62 0.77 2.76 4.72 9.95 1.0 1.7 4.5 5 5 0.07 5 5 5 0.25 0.25 0.31 2.85 4.87 9.95 0.1 0.1 0.2 OSI OSI 0.63 5 5 5 0.67 0.67 0.84 2.85 4.87 9.95 1.2 2.1 5.3 OS2 OS2 0.38 5 5 5 0.72 0.72 0.90 2.85 4.87 9.95 0.8 1.3 3.4 OS3 OS3 0.12 5 5 5 0.55 0.55 0.68 2.85 4.87 9.95 0.2 0.3 0.8
--- - --- - - --- - -- - - - -DEVELOPED TIME OF CONCENTRATION COMPUTATIONS Overland FloW, Time of Concentration: T _ 1.87(1.1-C * CJ)✓L Project: 685-002 'rabi• 3-f Calculations By: ATC ;-s½ RATJ:a(AL ltlZ'?PCD PltZ.QIJZNCY N:IJU!J'DGm'l' rAC1'0RS Date: April 15, 2013 GutterLSwale Flow, Time of Concentration: Ste-1-tw,n Period ~-=v i'•ctor T1= L/60V •> ' Tc = T; + T1 (Equation R0-2) Z t.o 10 1.00 } (EquaUon RO-4) l1 to 25 l.10 Velocity (Gutter Flow). V = 20·S11' 26 to 50 1.20 Velocity (Swale Flow), V = 15·$';, 51 to 100 1.25 Note; The P"OdUCt o! C tiluos c, Sh411ll not exceed. l , 00 NOTE, C-value for overland flows over grassy suriaces: C = 0.25 Overland Flow Gutter Flow Swale Flow Time of Concentration Design Basin Is Length C*C1 C*C1 C*C1 Length, Slope, T, T, T, Length, Slope, Velocity, T, Length, Slope, Velocity, T, 2-yr 10-yr 100-yr Point (2-yr (10-yr (100-yr L s 2-yr 10-yr 100-yr L s V L s V T, T, T, >500'? (min) (min) C1=1.00) C,=l.00) C,= 1.25) (ft) (%) (min) (min) (min) (ft) (%) CIVsl (ft) (%) (IVs) (min) (min) (min) I I No 0.95 0.95 1.00 17 2.00% 0.9 0.9 0.6 0 0.00% N/A N/A 0 N/A NIA NIA 5 5 5 2 2 No 0.95 0.95 1.00 92 0.50% 3.4 3.4 2.3 0 0.50% NIA NIA 0 NIA NIA NIA 5 5 5 3 3 No 0.34 0.34 0.42 15 2.00% 4.4 4.4 3.9 0 0.50% N/A NIA 0 NIA NIA NIA 5 5 5 4 4 No 0.62 0.62 0.77 94 3.50% 5.7 5.7 3.9 0 0.50% NIA NIA 0 NIA NIA NIA 6 6 5 5 5 No 0.25 0.25 0.31 27 14.00% 3.4 3.4 3.2 0 0.00% NIA NIA 0 NIA NIA N/A 5 5 5 OSI OSI No 0.95 0.95 1.00 150 1.00% 3.4 3.4 2.3 85 0.40% 1.26 I.I 0 NIA NIA N/A 5 5 5 0S2 0S2 No 0.95 0.95 1.00 150 1.00% 3.4 3.4 2.3 37 0.40% 1.26 0.5 0 NIA NIA N/A 5 5 5 0S3 0S3 No 0.95 0.95 I.DO 133 1.00% 3.2 3.2 2.2 0 0.00% NIA NIA 0 NIA NIA N/A 5 5 5
-------- - --- - -- - -- -DEVELOPED COMPOSITE% IMPERVIOUSNESS AND RUNOFF COEFFICIENT CALCULATIONS CHARACTER OF SURFACE: Runoff Percentage Coefficient Impervious Project: 685-002 Streets, Parking Lots, Roofs, Alleys, and Drives: Calculations By: ATC Asphalt ... 0.95 100% Date: April 15, 2013 Concrete . 0.95 90% Gravel. 0.50 40% Roofs. 0.95 90% Pavers .. 0.40 22% Lawns and LJJndscaping Sandy Soil .............. 0.15 0% Clayey Soil ........................................ 0.25 0% 2-year C, = 1.00 !()..year C. = 1.00 100-year C1 = 1.25 Runoff Coefficients are taken from the City of Fort Collins Storm Drainage Design Criteria and Construction Standards, Table 3-3. % Impervious taken from UDFCD USDCM, Volume I Area of Area of Area of Area of -Area of 2-year 10-year 100-year Basin ID Basin Area Basin Area Asphalt Concrete Roofs Gravel Lawns and Composite Composite Composite Composite (s.f.) (acl landscaping Runoff Runoff Runoff (ac) (ac) (ac) (acl (acl Coefficient Coefficient Coefficient % lmperv. 1 2178 0.05 0.050 0.000 0.000 0.000 0.000 0.95 0.95 1.00 100% 2 13068 0.30 0.000 0.000 0.300 0.000 0.000 0.95 0.95 1.00 90% 3 935 0.02 0.000 0.002 0.000 0.000 0.021 0.34 0.34 0.42 8% 4 25590 0.59 0.230 0.080 0.000 0.000 0.277 0.62 0.62 0.77 51% 5 3076 0.07 0.000 0.000 0.000 0.000 0.071 0.25 0.25 0.31 0% OS! 27443 0.63 0.113 0.000 0.236 0.092 0.188 0.67 0.67 0.84 58% OS2 16553 0.38 0.124 0.000 0.066 0.179 0.011 0.72 0.72 0.90 67% OS3 5238 0.12 0.038 0.000 0.000 0.038 0.045 0.55 0.55 0.68 44%
APPENDIX B
HYDRAULIC COMPUTATIONS
B.1 -Storm Sewers
~ iill,vrp s•-, f'p -----• -------ile:..il:)utl.., [POND OUTLET PIPE Elev. (ft) 4961.00 Sta 0+0 .00,Ou\1llH .+15.73 .. , .. Ln:11 ... Sta0+32.16,Ln: 2 1 1 1 1 Grnd:·EI 4953:00Rim El~4953:50--j--Rim-El~4,952:501----1------t------+----1--------Inv: E1:-41 48.:8011rlnv:-1:-4943·:88-out. -1nv:·E1:-4950:25-out··--t------+-------+----·· ----. Inv: I. 4950:17 In -·-·-·-·· -··----1----•--·-1---+----+----1----4958.00 --1·--1---1 --1--1------1---+-----+----+----+----+-----I----4955.00 4952.00 4949.00 4946.00 ··················I·· 1---············I· ! .. I 1------1 ---1 ·---------·-----·1----------·l---------l------,c-I---I----+----I ,. ___________ · j ···I· I · .......... ···I ~ ................. ::,.•·•·•·:'f.:T=l~l:>~--~c:::_::~~·.·.·.•··••·••····••··•·••··•1··· I 1-------I •..••.•••.•...•••....••.•.........•..•. I ···············I····· ······I"· I I I· I···· I ················ 1············1·•·····•>~~~(~~:~~t~···· ✓r4f -· i01I--+-------·I· I t-----I ---··· ••.-1----is:73U~~-;,-;;r;~~l,; J•.········•··· -• ···I··"-·· --1 .. I ----··I"· I ·······-1----t------+----1----1------i----1 ----I --~----!---------1-------1 ··········I· --·-------~------~-------~------~------~~-------'---------'-------'-----------· 0 10 20 30 40 50 Reach (ft) 60 70 80 90 100 Hydraflow Storm Sewers 2005
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Storm Sewer Summary Report
Line Line ID ' I Flow Line Line Invert
No. rate size length EL Dn
(els) (in) (ft) (ft)
1 8.70 18 C 15.7 4948.80
2 8.70 18 C 16.4 4950.17
Project File: PondOutlet.stm
NOTES: C = cir; e = emp: b = box; Return period = 2 Yrs.
Page 1
Invert Line HGL HGL Minor HGL Dns
EL Up slope down up loss Junct line
(ft) (%) (ft) (ft) (ft) (ft) No.
4948.88 0.509 4949.93 4950.17 0.42 4950.59 End
4950.25 0.487 4951.30 4951.55 0.44 4952.00 1
Number of lines: 2 I Run Date: 04-30-2013
•ydlaul's G.~ Ltli:c ca.1n t•s --- -- - -- --• 1 Line Size Q Downstream Len Upstream Check JL Minor coeff loss Invert HGL Depth Area Vel Vel EGL Sf Invert HGL Depth Area Vel Vel EGL Sf Ave Enrgy elev elev head elev elev elev head elev Sf loss (In) (els) (ft) {ft) (ft) (sqft) (ft/s) (ft) (ft) (%) (ft) (ft) (ft) (ft) (sqft) (ft/s) (ft) (ft) (%) (%) (ft) (K) (ft) 1 18 8.70 4948.80 4949.93 1.13 1.42 6.11 0.58 4950.51 0.824 15.7 4948.88 4950.17 1.29 1.62 5.37 0.45 4950.62 0.634 0.729 0.115 0.94 0.42 2 18 8.70 4950.17 4951.30 1.13' 1.42 6.11 0.58 4951.88 0.824 16.4 4950.25 4951.55 1.30 1.63 5.34 0.44 4952.00 0.627 0.725 0.119 1.00 0.44 Project File: PondOutlet.stm I Number of lines: 2 I Run Date: 04-30-2013 Notes: • Critical depth assumed. Hydraflow Storm Sewers 200~
St n illlll,, r 'j r: ! - - - - - - - - - - - -Pr-N.., Elev. (ft) 4971.00 Sta 6 -1-n: 1 . I ' Grn . 2:7i9----1----+-----+---························· ................ -l1c-----=c---1----+--1nv. I. 4959.00 Out I I I -1--4968.00 I e---I I .. + ·············I·· 4965.00 1 I 1 ___ c -j 7 4962.00 ~-----=--=-1==R=+=~===t===~==t===t==J====I-r------,·--·--·+-t--r-------i------t-----f------+------1------t----4959.00 1b.66IX;;::l0'"~~,:J;/~-·I--+-----+-----+----+----+-----I I ---·······I-----1 r ········· I 4955_00 -1 40 0 10 20 30 50 Reach (ft) -_L ______ 60 70 80 90 !STORM B I · 1 ... 1 i ··· l I ' 100 Hydraflow Storm Sewers 2005
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Storm Sewer Summary Report
Line Line ID Flow Line Line Invert
No. rate size length ELDn
(els) (in) (ft) (ft)
1 1.20 10 C 15.7 4958.69
Project File: New.stm
NOTES: c = cir; e = ellip; b = box; Return period = 2 Yrs.
Page
Invert Line HGL HGL Minor HGL Dns
EL Up slope down up loss Junct line
(ft) (%} (ft) (ft) (ft) (ft) No.
4959.00 1.980 4959.06 4959.49 0.20 4959.49 End
Number of lines: 1 I Run Date: 04-30-2013
' t r ~~li;!w.'!""":ii!Fi'~" ,J~' ...._ 1· ,_y'-u '")"" a q•,1 : !('. •• ...,,,~. • ~. .........,. I • Cu;,., . , ..... -.,'" .•. '.!'!.' .. , · .. •~ .. ' .• ·~. ·.·•'"'· .,,,," .... r--e ·llt!!'!!""!'ali-Slll-,"_ '.'-: -. . . . ' ;·".,''?'.'_· ·\·,·::-,. -", • '",."' . "" -:-• ' . '', ' ' '' ' ,-'. '~.~.:-·-.~~·-~,~~~. ~'""IC,·-~·,,, : !"' ~'.'\F":· .... ~1 - - -... Line Size Q Downstream Len Upstream Check JL Minor coeff loss Invert HGL Depth Area Vel Vel EGL Sf Invert HGL Depth Area Vel Vel EGL Sf Ave Enrgy elev elev head elev elev elev head elev Sf loss (In) (els) (ft) (ft) (ft) (sqft) (ft/s) (ft) (ft) (%) (ft) (ft) (ft) (ft) (sqft) (ft/s) (ft) (ft) (%) (%) (ft) (K) (ft) 1 10 1.20 4958.69 4959,06 0.37 0,24 5.08 0.40 4959.46 0.720 15.7 4959,00 4959.49 0.49 .. 0.33 3,62 0.20 4959.69 0.721 0.721 n/a 1.00 0.20 Project File: New.stm I Number of lines: 1 I Run Dale: 04,30,2013 Notes: : •• Critical depth. Hydraflow Storm Sewers 200~:, ~~ -·,:'.;»;r;.-.,' ,,._.:..e:'1,il,,i_, ',,,)'; ,i!£:;.·i. «K '.:,•~ -' ,: _,...__,, ~, .••• :!~ , .•. ,. . .,. ~;,_, . .iill
APPENDIX C
WATER QUALITY DESIGN COMPUTATIONS
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WATER QUALITY POND DESIGN CALCULATIONS
Water Qualitv Pond
Project: 685-002
By:ATC
Date: 4.24.13
REQUIRED STORAGE & OUTLET WORKS:
BASIN AREA= 0.590 <--INPUT from impervious calcs
BASIN IMPERVIOUSNESS PERCENT = 51.00 <--INPUT from impervious calcs
BASIN IMPERVIOUSNESS RATIO = 0.5100 <--CALCULATED
WQCV (watershed inches) = 0.209 <--CALCULATED from Figure EDB-2
WQCV (ac-ft) = 0.012 <·-CALCULATED from UDFCD DCM V.3 Section 6.5
WQ Depth (ft) = 1.000 <--INPUT from stage-storage table
AREA REQUIRED PER ROW, a (in 2 ) = 0.054 <--CALCULATED from Figure EDB-3
CIRCULAR PERFORATION SIZING:
dia (in) = 1/4 <--INPUT froni"Figure 5
n= 3.000 <-· INPUT from Figure 5
t (in)= 0.500 <--INPUT from Figure 5
number of rows = 1.000 <--CALCULATED from WQ Depth and row spacing
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WATER QUALITY POND STAGE STORAGE TABLE
Project: 68S-002
Date: 4/24/2013
By: ATC
ELEV AREA CONIC
INC. VOL.
(FT) {SF) {CF)
4951.5 0 0
4952 230 53
4953 1670 169
CONIC CONIC
TOTAL VOL. TOTAL VOL.
(CF) (AC-FT)
0 0.000
53 0.001
1723 0.040
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Area Inlet Performance Curve:
Water Quality Pond Outlet
Governing Equations:
At low flow depths, the inlet will act like a weir governed by lhe following equation: Q 3 . 0 p H I .S
• where P = 2(L + W)
• where H corresponds to the depth of water above the flowline
At higher flow depths, the inlet will act like an orifice governed by the following equation:
• where A equals the open area of the inlet grate
Q 0.67 A(2gH )0
'
* where H corresponds to the depth of water above the centroid of the cross-sectional area (A)
The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown.
However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation
will cross at a certain flow depth. The two curves can be found below:
ta e -0isc a
If H > 1. 792 (NP), then the grate operates like an orifice; otherwise it operates like a weir.
Input Parameters:
Type of Grate:
Length of Grate (ft):
Width of Grate (ft):
Open Area of Grate (ft 2):
Flowline Elevation (ft):
Allowable Capacity:
Depth vs. Flow:
Depth Above Inlet (ft)
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
(4) Neenah R-3409
2.5
2.5
4.06
0.000
50%
Elevation
(ft)
0.00
0.10
0.20
0.30
0.400
0.50
0.60
0.70
0.80
0.90
0.996
Shallow
Weir Flow
(els)
0.00
0.47
1.34
2.46
3.79
5.30
6.97
8.71
10.65
12.72
14.91
Inlet S is desi ned to interce t the full 100-ear flow of 8.2 els u
Orifice
Flow
(els)
0.00
3.45
4.88
5.98
6.90
7.71
8.45
9.10
9.73
10.33
10.89
Actual
Flow
(els)
0.00
0.47
1.34
2.46
3.79
5.30
6.97
8.71 ~ 100-year depth
9.73
10.33
10.89
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NorthernEnaineerlna.com // 970.221.4158
August 5, 2013
Prepared for:
Encompass Technologies
324 Jefferson Street
Fort Collins, CO 80524
Prepared by:
NORTHERN
ENGINEERING
200 South College Avenue, Suite 10
Fort Collins, Colorado 80524
Phone: 970.221.4158 Fax: 970.221.4159
www.northernengineering.com
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NORTHERN
ENGINEERING
August 5, 2013
Encompass Technologies
324 Jefferson Street
Fort Collins, CO 80524
ADDRESS:
200 S. College Ave. Suite 10
Fort Collins, CO 80524
RE: Stormwater Management Plan
River District Block One Mixed Use
Fort Collins, CO
To whom it may concern:
PHONE: 970.221.4158 WEBSITE:
FAX: 970.221.4159 www. norther nengi neeri ng.com
Northern Engineering Services, Inc. is pleased to submit this Stormwater Management Plan and Erosion
Control Report for the River District Block One Mixed Use development project. This report outlines Best
Management Practices (BMPs) to be implemented with the proposed construction in order to minimize
potential pollutants in stormwater discharges.
We have prepared this report to accompany the Colorado Department of Public Health and Environment
General Permit for Stormwater Discharge Associated with Construction Activities (aka, Stormwater Discharge
Permit or SOP). Please note: this Stormwater Management plan (including the Site Maps) is a dynamic
device that should be kept current and logged as construction takes place. As such, this version was
prepared to facilitate initial plan approvals and permitting, but does not necessarily reflect the final version, or
the transitions throughout the construction process. As the site develops and changes, the Contractor is
expected and encouraged to make changes to what is contained herein so that the SWMP works as effectively
and efficiently as possible. It shall be the responsibility of the SWMP Administrator and/or the permit holder
(or applicant thereof) to ensure the plan is properly maintained and followed.
If you should have any questions or comments as you review this report, please feel free to contact us at your
convenience.
Sincerely,
NORTHERN ENGINEERING SERVICES, INC.
Aaron Cvar,PE
Project Engineer
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NORTHERN
Et/GI NEERING River District Block One Mixed Use SWM P
TABLE OF CONTENTS
Vicinity Map
1.0 General Requirements ............................................................................................... 1
1.1
1.2
1.3
1.4
2.0
2.1
2.2
2.3
2.4
2.5
Objectives .................................................................................................................. 1
SMWP Availability ...................................................................................................... 1
Definitions .................................................................................................................. 1
Additional Permitting ................................................................................................... 1
Narrative Site Description .......................................................................................... 2
Existing Site Description .............................................................................................. 2
Nature of Construction Activity ..................................................................................... 2
Sequence of Major Activities ......................................................................................... 2
Site Disturbance ......................................................................................................... 2
Existing Vegetation ...................................................................................................... 2
2.6 Potential Pollution Sources ........................................................................................... 3
2.7 Non-stormwater discharges .......................................................................................... 3
2.8 Receiving Waters ........................................................................................................ 3
3.0
3.1
Stormwater Management Controls .............................................................................. 4
SWMP Administrator ................................................................................................... 4
3.2 Best Management Practices (BMP's) for Stormwater Pollution Prevention .......................... 4
3.3
3.4
3.5
3.6
3.7
3.8
Structural Practices for Erosion and Sediment Control ..................................................... 4
Phased BMP Installation I ............................................................................................. 5
Nonstructural Practices for Erosion and Sediment Control ................................................ 8
Material Handling and Spill Prevention ........................................................................ 10
Dedicated Concrete or Asphalt Batch Plant.. ................................................................ 11
Vehicle Tracking Control ............................................................................................ 11
3.9 Waste Management and Disposal ............................................................................... 11
3.10
4.0
4.1
4.2
5.0
5.1
5.2
5.3
6.0
References
Groundwater and Stormwater Dewatering .................................................................... 12
Final Stabilization and Long-Term Stormwater Management ........................................ 13
Final Stabilization ..................................................................................................... 13
Long-Term Stormwater Management.. ......................................................................... 13
Inspection, Maintenance and Record Keeping ............................................................ 14
BMP Inspection ........................................................................................................ 14
BMP Maintenance .................................................................................................... 14
Record Keeping ........................................................................................................ 14
Additional SWMP and BMP Resources ...................................................................... 16
17
Stormwater Management Plan
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NORTHERN
ENGI.N£[RING Riv.er District Block One Mixed Use SWMP
APPENDICES:
APPENDIX A -Phasing Plan, Site Maps
APPENDIX B Erosion Control Details
APPENDIX C Copies of Permits/Applications (to be provided by contractor)
APPENDIX D -Stormwater Management Plan Inspection Logs
APPENDIX E Contractor Inserts (as needed) . .
' '·: · · APPENDIX F -Reference Material
-:~/~-.. ~·:-
"''-~>• ~, -
Stormwater Management Plan
x·rit ·g 'L 1 r rr er·
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1.0
1.1
NORTHERN
ENGINEERING
General Requirements
Objectives
River District Block One Mixed Use SWMP
The objective of a Stormwater Management Plan (SWMP) is to identify all potential sources of
pollution likely to occur as a result of construction activity associated with the site construction, and
to describe the practices that will be used to reduce the pollutants in stormwater discharges from
the site. The SWMP must be completed and implemented at the time the project breaks ground,
and revised as necessary as construction proceeds to accurately reflect the conditions and practices
at the site.
This report summarizes the Stormwater Management Plan for the construction activity that will
occur with the River District Block One Mixed Use development project in Fort Collins, CO. This
plan has been prepared according to regulations of the Colorado Department of Public Health and
Environment (CDPHE), Water Quality Control Division.
1.2 SMWP Availability
This report is intended to remain on the aforementioned construction site to allow for maintenance
and inspection updates, and for review during inspection.
1.3 Definitions
BMP -Best Management Practice encompassing a wide range of erosion and sediment control
practices, both structural and non-structural in nature, which are intended to reduce or eliminate
any possible water quality impacts from stormwater leaving a construction site.
Erosion Control BMPs -Practices that PREVENT the erosion of soil, such as minimizing the amount
of disturbed area through phasing, temporary stabilization, and preserving existing vegetation
Sediment Control BM P's -Practices to REMOVE sediment from runoff, such as sediment basins,
silt fence, or inlet protection.
Non-structural BM P's -The implementation of methods, practices, and procedures to minimize
water quality impacts, such as the preservation of natural vegetation, preventive maintenance and
spill response procedures.
Structural BM P's -Physical devices that prevent or minimize water quality impacts, such as
sediment basins, inlet protection, or silt fence.
1.4 Additional Permitting
As mentioned above, this Stormwater Management Plan is associated with the Colorado
Department of Public Health and Environment Stormwater Permit that is issued by the Water
Quality Control Division of the CDPHE. Additional Environmental permitting not described in this
report will likely be required as a part of this project. An example is the Construction Dewatering
Permit for groundwater, which will be discussed later. Another example is the Air Pollution
Emission Notice (APEN). The CDPHE website contains links to both of these permits, as well as
many other potential permits. The Contractor is responsible for ensuring the proper permits are
acquired.
I Stormwater Management Plan
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N ? NORTHERN
--=:., f_Nr;JNEERING
2.0
2.1
Narrative Site Description
Existing Site Description
River District Block One Mixed Use SWMP
The project site is located in the northwest quarter of Section 12, Township 7 North, Range 69
West of the 6th Principal Meridian, in the City of Fort Collins, Larimer County, Colorado. The site
consists of a vacant downtown area. Existing ground cover consists of gravel, and a concrete pad.
The site is bounded on the northeast by the Cache La Poudre River, on the northwest by Linden
Street, and on the south by the existing Ranchway Feeds industrial site.
According to the United States Department of Agriculture (USDA) Natural Resources Conservation
Service (NRCS) Soil Survey, the site consists of Paoli fine sandy loam, which falls into Hydrologic
Soil Group B. More site-specific exploration found varying materials including sandy clay with
occasional sand layers and sandy gravel. Please see the Geotechnical Engineering Report by Earth
Engineering Consultants, Inc. for additional information.
2.2 Nature of Construction Activity
The proposed project will develop the majority of the existing site, constructing a commercial
building of several stories in height. Parking areas and associated utilities will be constructed. A
water quality pond will be constructed at the northeast corner of the site. Utilities will be installed
in support of the new buildings, along with the appropriate stormwater facilities. Water quality to
mitigate and treat stormwater runoff from the site is included in a water quality pond located in the
northeast portion of the site.
2.3 Sequence of Major Activities
To complete the project, many basic construction activities will take place. The project will begin
by stripping the site of topsoil, followed by overlot grading. The installation of utilities will occur
next, including water, sewer, and storm sewer. Once overlot grading is complete, and utilities have
been installed, it is anticipated that construction of the building foundations will begin. While
building foundations are being constructed, curb and gutter will be installed throughout the project,
followed by asphalt paving of the parking areas. Vertical construction of the buildings is expected to
commence once the public infrastructure has been inspected by the city. Fine grading of the areas
around the buildings, and the installation of landscaping throughout the project will follow. The
final stage of construction will be the construction of the buildings, along detailed grading around
each building and installation of landscaping.
2.4 Site Disturbance
The entire project boundary/ total disturbance area is approximately 1.0 acre.
2.5 Existing Vegetation
The existing site vegetation consists primarily of sparse grasses. As stated previously, primary
ground cover is gravel and an existing concrete pad. What grasses do exist naturally grow in
clumps, which inevitably leads to some bare areas. In general, the site has an estimated 10%
vegetative cover. It is highly recommended that pre-construction photos be taken by the
contractor to clearly document vegetative conditions prior any disturbance activities.
Stormwater Management Plan 2
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N S i NORTHERN ....5 I fNGINE[RING River District Block One Mixed Use SWMP
2.6 Potential Pollution Sources
As is typical with most construction sites, there are a number of potential pollution sources which
could affect water quality. It is not possible for this report to identify all materials that will be used
or stored on the construction site. It is the sole responsibility of the Contractor to identify and
properly handle all materials that are potential pollution sources. The following are some common
examples of potential pollution sources:
• Exposed and stored soils
• Management of contaminated soils
• Off-site tracking of soils and sediment
• Loading and unloading operations
• Outdoor storage of building materials, fertilizers, chemicals, etc.
• Vehicle and equipment maintenance and fueling
• Significant dust or particulate generating processes
• Routine maintenance activities involving fertilizers, pesticides, detergents, fuels, solvents, oils, etc.
• On-site waste disposal practices (waste piles, dumpsters, etc.)
• Concrete truck/equipment washing
• Non-industrial waste sources that may be significant, such as worker trash and portable toilets
• Uncovered trash bins
• Other areas or procedures where potential spills can occur
• Stockpiling of materials that can be transported to receiving waterway(s)
2.7 Non-stormwater discharges
The Stormwater Construction Permit only covers discharges composed entirely of stormwater.
Exceptions include emergency fire fighting activities, landscape irrigation return flow,
uncontaminated springs, construction dewatering (caused by storm events) and concrete washout
water. Proper treatment and use of BMPs is still required for these exceptions when available.
The discharge of pumped stormwater, ONLY, from excavations, ponds, depressions, etc. to surface
waters, or to a municipal storm sewer system is allowed by the Stormwater Construction Permit, as
long as the dewatering activity and associated BMPs are identified in the SWMP are implemented
in accordance with the SWMP.
Aside from the exceptions noted above, non-stormwater discharges must be addressed in a separate
permit issued for that discharge. If groundwater is encountered, and dewatering is required, a
Construction Dewatering Permit must be acquired from the Colorado Department of Public Health
and Environment.
2.8 Receiving Waters
Stormwater runoff from the project area will generally sheet flow into the Cache La Poudre River,
which is located along the northeast boundary of the development site. The proposed post-
development drainage pattern generally follows the historic drainage course.
Stormwater Management Plan 3
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N's I NORTHERN _s ) [NGINE[RING River District Block One Mixed Use SWMP
3.0 Stormwater Management Controls
3.1 SWMP Administrator
A SWMP Administrator must be designated in conjunction with the Stormwater Permit. This person
shall be responsible for developing, implementing, maintaining, and revising the SWMP. The
SWMP Administrator will also be the contact for all SWMP-related issues and will be the person
responsible for the accuracy, completeness, and implementation of the SWMP. The Administrator
should be a person with authority to adequately manage and direct day-to-day stormwater quality
management activities at the site.
Please note: It is the responsibility of the SWMP Administrator to evaluate the proposed BMPs as
shown on the Stormwater Management Plan and modify the Plan as necessary throughout the
construction process. The final decision on where all BMPs will be located and when they will be
installed shall be made by the SWMP Administrator. All documentation throughout the
construction process shall also be the responsibility of the SWMP Administrator.
The SWMP Administrator for this site is (to be filled in by the SWMP Administrator, when
selected):
Name:
Company:
Phone:
E-mail:
3.2 Best Management Practices (BMP's) for Stormwater Pollution Prevention
Beginning from mobilization, and throughout the entire construction of the buildings, erosion control
devices shall be installed to ensure minimal pollutant migration. These erosion control devices may
be installed in phases, or not at all, depending on actual conditions encountered at the site. It is
the responsibility of the Contractor to make the ultimate determination as to what practices should
be employed and when. In the event that a review agency deems onsite erosion control measure to
be insufficient, it shall be the responsibility of the contractor to implement modifications as directed.
Best Management Practices (BMPs) are loosely defined as a method, activity, maintenance
procedure, or other management practice for reducing the amount of pollution entering a water
body. The term originated from rules and regulations in Section 208 of the Clean Water Act.
Details for Structural and Non-Structural BMPs have been included in Appendix B. These details
should be used for additional information on installation and maintenance of BMPs specified in this
report. It is also intended to serve as a resource for additional BMPs that may be appropriate for
the site that have not specifically been mentioned in the report.
3.3 Structural Practices for Erosion and Sediment Control
Structural BMPs are physical devices that are implemented to prevent erosion from happening or to
limit erosion once it occurs. These devices can be temporary or permanent, and installation of
individual components will vary depending on the stage of construction. Please refer to the
Stormwater Management Plan (Appendix A) for the proposed location of all BMPs. Construction
Details for Temporary BMPs are located in the Appendix for reference. As noted above, it is the
Stormwater Management Plan 4
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responsibility of SWMP Administrator to evaluate the proposed BMPs as shown on the Stormwater
Management Plan and modify the plan as necessary throughout the construction process.
3.4 Phased BMP Installation
It is important to recognize the four (4) major Development Phases as defined by the State of
Colorado's Stormwater Discharge Permit (SDP). These four development phases have been
distinguished to aid in the appropriate timing of installation/implementation of BMPs at different
stages of the construction process. These phases are described as follows:
Phase I -Grading Stage; BMPs for initial installation of perimeter controls
Phase II -Infrastructure Stage; BMPs for utility, paving and curb installation
Phase Ill -Vertical Construction Stage; BMPs for individual building construction.
Phase IV -Permanent BMPs and final site stabilization.
The following is a rough estimate of the anticipated construction sequence for site improvements.
The schedule outlined below is subject to change as the project progresses and as determined by
the General Contractor.
Table 1 -Preliminary Permit and Construction Schedule
BEGINNING "BMP PHASE OF
TASK DATE ENDING DATE DEVELOPMENT"
Development Construction Permit
Issued by City of Fort Collins August, 2013 I
Overlot Grading August, 2013 August, 2013 I
Utility Installation August, 2013 September, 2013 II
September,
Building Construction 2013 May, 2014 111
Final Stabilization May, 2014 July, 2014 IV
Included in the back map pockets are the Site Plans: a "Static" Site Plan and a "Dynamic" Site
Plans (one for each phase of construction). The "Static" plan serves to display the overall
management plan all at once. However, proper implementation of BMPs does not occur at once,
and certain BMPs may move location in the construction process; therefore, the "Dynamic" Site
Plan is intended for the Contractor to write in the BMP symbols to document the location and time
the BMPs are installed and maintained throughout the entire construction process.
Stormwater Management Plan 5
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Silt Fencing (Phase I)
Silt fencing shall be provided to prevent migration of sediment off-site or into adjacent
properties. All silt fencing shall be installed prior to any land disturbing activity (stockpiling,
stripping, grading, etc.). Silt fencing is to be installed prior to site excavation or earthwork
activities.
Inspections of the silt fence should identify tears or holes in the material, and should check
for slumping fence or undercut areas that allow flows to bypass the fencing. Damaged
sections of fencing should be repaired or replaced to ensure proper functioning. Sediment
accumulated behind the silt fence should be removed to maintain BMP effectiveness,
typically before it reaches a depth of 6 inches.
Vehicle Tracking Control Pads (Phase I)
Vehicle tracking control pads shall be provided to minimize tracking of mud and sediment
_onto paved surfaces and neighboring roadways. All vehicle tracking control pads shall be
installed prior to any land disturbing activity (stockpiling, stripping, grading, etc.). Location
of vehicle tracking control pads will be located at any and all existing and future vehicle
accesses being used during any of the construction phases. These locations will primarily be
dictated by gates or openings in the temporary construction fencing that is expected to be
installed. Vehicle tracking control pads are to be installed prior to site excavation or
earthwork activities.
Vehicle tracking pads should be inspected for degradation and aggregate material should be
replaced as needed. If the area becomes clogged with water, excess sediment should be
removed. Aggregate material should remain rough, and at no point should aggregate be
allowed to compact in a manner that causes the tracking pad to stop working as intended.
Sediment Control Log -aka "Straw Wattles" (Phase I)
A Sediment Control Log is a linear roll made of natural materials, such as straw, coconut
fiber, or other fibrous material trenched into the ground and held with a wooden stake.
Sediment Control Logs can be used in many instances. Examples include perimeter control
for stockpiles, as part of inlet protection designs, as check dams in small drainage ways, or
on disturbed slopes to shorten flow lengths.
Sediment Control Logs should be inspected for excess sediment accumulation. Sediment
should be removed prior to reaching half the height of the log.
At a minimum, Sediment Control Logs should be used around soil stockpiles and for inlet
protection in unpaved areas of the site.
Curb Inlet Protection (Phase I & II)
Curb inlet protection shall be provided for existing curb inlets to prevent sediment transport
from adjacent earthwork disturbance. Installation of these filters shall occur before adjacent
earthmoving activities (Phase I implementation). Wattle type filters are to be implemented
for new and existing inlets where asphalt is not yet installed. For these inlets, if pavement is
constructed adjacent to the structure or if the area adjacent to the inlet is changed such that
the wattle type filter is no longer effective, it shall be the responsibility of the Contractor to
ensure that an appropriate method is used instead. For example, the wattle filter could be
reused, or a gravel-block inlet filter may be installed. It will be left to the discretion of the
Contractor as to whether replacement of any inlet filter is necessary.
Inlet protection should be inspected regularly for tears that can result in sediment entering
Stormwater Management Plan 6
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an inlet. Inlet protection should also be inspected for sediment accumulation upstream of
the inlet, and sediment should be removed when the less than half of the capacity is
available, or per manufacturer specifications.
Erosion Control Blankets (Phase II)
A temporary degradable rolled erosion control product composed of natural flexible fibers
shall be used on all seeded slopes 3: 1 and greater (excluding mulched shrub bed areas).
Erosion control blankets should be utilized to provide erosion control and to facilitate
vegetation establishment. During installation, it is important to ensure that no gaps or voids
exist under the material and that all corners of the material are secured using stakes and
trenching. Stakes should be made of materials that are biodegradable. Continuous contact
between the product and the soil is necessary to avoid failure.
Erosion Control Blankets should be inspected regularly for signs of erosion, including
beneath the mat. If voids are apparent, they should be filled with suitable soil. Inspections
should also identify loose or damaged stakes, as well as loose portions of the blanket. If
deficiencies are found, they should be repaired or replaced.
Concrete Washout Area (Phase Ill
A concrete washout should be provided on the site. The washout can be lined or unlined
excavated pits in the ground, commercially manufactured prefabricated containers, or
aboveground holding areas. The concrete washout must be located a minimum of 400 feet
from any natural drainage way or body of water, and at least 1000 feet from any wells or
drinking water sources. Washout areas should not be located in an area where shallow
groundwater may be present. Contractor shall clearly show the desired location and access
to the Concrete Washout Area on the Stormwater Management Plan -Dynamic Site Plan.
Contractor shall place a Vehicle Tracking Pad if the selected location for the Concrete
Washout Area is detached from pavement. Clear signage identifying the concrete washout
should also be provided.
The Concrete Washout Area should be inspected regularly. Particular attention should be
paid to signage to ensure that the area is clearly marked. Confirmation that the washout is
being used should also be noted to ensure that other undesignated areas of the site are not
being used •incorrectly as a concrete washout.
Sediment Trap (Phase Ill
Sediment traps are formed by excavating an area or by placing an earthen embankment
across a low area or drainage swale. Sediment Traps are designed to capture drainage from
disturbed areas less than one acre and allow settling of sediment.
Sediment Traps should be inspected for stability and seepage. Accumulated sediment
should be removed as needed to maintain the effectiveness of the sediment trip, typically
when the sediment depth is half the height of the outflow embankment.
A Sediment Trap shall be installed at the outlet structure of the Water Quality Pond as soon
as possible upon completion of the outlet structure, and will remain in place until the project
site has been stabilized. The Sediment Trap will help reduce sediment discharge into the
receiving drainage way by filtering at the pond outlet.
Riprap (Phase Ill
Considered a permanent BMP, riprap pads will be provided to prevent long term erosion and
scour at the outlets of storm lines and other critical scour locations. Riprap pads will be
Stormwater Management Plan 7
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3.5
placed at specified storm sewer outfalls and other critical locations as soon as possible
following construction of the respective facility. The riprap pads will be inspected regularly
and any required maintenance will be performed as discussed in subsequent sections.
PermanenVEstablished Vegetation (Phase IV)
Permanent or established vegetation and landscaping is considered a permanent form of
sediment and erosion control for common open spaces, steep slopes and areas not exposed
to prolonged scour velocities, or acute incipient motion bed shear stresses that will create
soil erosion, rill formation and subsequent sediment transport. Areas where the previous
conditions apply will contain sufficient permanent BMPs, such as.riprap and Erosion Control
Blankets. Permanent/Established vegetation defines Phase IV of development.
Non-Structural Practices for Erosion and Sediment Control
Non-Structural BMPs are practices or activities that are implemented to prevent erosion from
happening or to limit erosion once it occurs. These BMPs can be a practice resulting in physical
change to the site, such as mulching or slope stabilization. They can also result in behavioral
changes on the site, such as changes to construction phasing to minimize exposure to weather
elements, or increased employee awareness gained through training.
Protection of Existing Vegetation (Phases I-IV)
Protection of existing vegetation on a construction site can be accomplished through
installation of a construction fence around the area requiring protection. In cases where
upgradient areas are disturbed, it may also be necessary to install perimeter controls to
minimize sediment loading to sensitive areas such as wetlands.
Trees that are to remain after construction is complete must be protected. Most tree roots
grow within the top 12"-18" of soil, and soil compaction is a significant threat to tree
health. As such, particular care should be taken to avoid activities within the drip-line of
the tree. Direct equipment damage should also be prevented. The most effective way to
ensure the health of trees is to establish a protection zone at the drip-line of the tree to
prevent unintended activity in the area directly surrounding the tree.
Fencing should be inspected and repaired when needed. If damage occurs to a tree, an
arborist should be consulted on how to care for the tree. If a tree is damage beyond repair,
the City Forester should be consulted on remediation measures.
At a minimum, trees located along the canal realignment should be protected, as should the
existing vegetation found in the wetland areas on the north side of the site.
Stormwater Management Plan 8
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Stockpile Management (Phases 1-111)
Stockpile management should be utilized to minimize erosion and sediment transport from
soil stockpiles. In general, soil stockpiles should be located a minimum of 100 feet from
any drainage way and 50 feet from any storm sewer inlets. Where practical, choose a
stockpile location that will remain undisturbed for the longest period of time as the phases
of construction progress. Sediment control BMPs should be placed around the perimeter of
the stockpile, and a designated access point on the upstream side of the stockpile should be
identified. BMPs such as surface roughening, temporary seeding, mulching, erosion control
blankets, or soil binders should be used to stabilize the stockpile surface.
As a part of stockpile management, regular inspections of the perimeter controls should be
completed. If BMPs have been utilized to stabilize the surface of the stockpile, they should
be inspected and repaired as needed.
Mulching (Phase 1-111)
Mulching helps reduce erosion by protecting bare soil from rainfall impact, increasing
infiltration, and reducing runoff. Although often applied in conjunction with temporary or
permanent seeding, it can also be used for temporary stabilization of areas that cannot be
reseeded due to seasonal constraints. The most common type of mulch used is hay or grass
that is crimped into the soil to keep it secure. However, crimping may not be practical on
slopes steeper than three to one (3H: 1 V).
The Contractor shall mulch all planted areas within twenty-four (24) hours after planting.
Only weed-free and seed-free straw mulch may be used. Straw mulch should be applied at
two (2) tons per acre, and shall be adequately secured by crimping, tackifier, netting or
blankets. Hydraulic mulching may also be used on steep slopes or where access is limited.
In the case that hydraulic mulching is utilized, the Contractor shall use wood cellulose fibers
mixed with water at two thousands to two thousand five hundred (2,000-2,500) pounds
per acre and organic tackifier at one hundred to four hundred (100-400) pounds per acre.
Wind Erosion/Dust Control (Phase I-IV)
Wind Erosion and Dust Control BM P's help to keep soil particles from entering the air as a
result of land disturbing construction activities. Examples include use of a water truck or
irrigation/sprinkler system to wet the top layer of disturbed soil, seeding and mulching, soil
binders, or wind fences.
If a water truck or irrigation/sprinkler system is utilized, monitoring to ensure that sufficient
water is applied is crucial to ensuring soil particles don't become airborne. Equally
important is monitoring for overwatering, as too much water can lead to increased erosion.
Good Housekeeping Practices (All phases)
Good housekeeping practices that will prevent pollution associated with solid, liquid, and
hazardous construction-related materials and wastes should be implemented throughout the
project. Examples of good housekeeping include providing an appropriate location for waste
management containers, establishing proper building material staging areas, designating
paint and concrete washout areas, establishing proper equipment/vehicle fueling and
maintenance practices. Development of a spill prevention and response plan is another
example of Good Housekeeping practices that should be used on the project. The following
items are detailed examples of some of the good housekeeping practices that should be
utilized throughout the project.
Street Sweeping and Vacuuming -Street sweeping and vacuuming should be used to
Stormwater Management Plan 9
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3.6
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remove sediment that has been tracked onto adjacent roadways. Roadways should be
inspected at least once a day, and sediment should be removed as needed. A check of inlet
protection should be completed after sweeping to ensure nothing was displaced during
sweeping operations.
Waste Management -Designate trash and bulk waste collection areas on-site. When
possible, materials should be recycled. Hazardous material waste should be segregated
from other solid waste. Waste collection areas should be located away from streets, gutters,
watercourses, and storm drains. Dumpsters should be located near site entrances to
minimize traffic on disturbed soils, and they should be placed on a level soil surface.
Establish Proper Building Material Handling and Staging areas -Clearly designate site
areas for staging and storage of building materials. Provide appropriate BMPs to ensure
that spills or leaks are contained.
Establish Proper Equipment/Vehicle Fueling and Maintenance Practices -If needed, create
a clearly designated on-site fueling and maintenance area that is clean and dry. Provide
appropriate BMPs to ensure that spills or leaks are contained.
Saw Cutting Pollution Prevention (Phase II)
The following protocol is recommended to prevent dust and slurry from asphalt and concrete
saw cutting activities from migrating into the existing storm drain system.
Slurry and cuttings shall be vacuumed during cutting and surfacing operations
Slurry and cuttings shall not remain on permanent concrete or asphalt pavement
overnight
Slurry and cuttings shall not drain to any natural or constructed drainage
conveyance
Collected slurry and cuttings shall be disposed of in a manner that does not violate
groundwater or surface water standards
Material Handling and Spill Prevention
Potential pollution sources, as discussed in earlier sections, are to be to be identified by the
Contractor. Spill prevention procedures are to be determined and put in place prior to construction
by the Contractor. A spill and flooding response procedure must also be determined and put in
place prior to construction by the Contractor. Additionally, steps should be taken to reduce the
potential for leaks and spills to come in contact with stormwater runoff, such as storing and
handling toxic materials in covered areas or by storing chemicals within berms or other secondary
containment devices.
A notification procedure must be put in place by the Contractor, by which workers would first notify
the site construction superintendent, who would then notify the SWMP Administrator. Depending
on the.severity of the spill, the site construction superintendent and SWMP Administrator would
possibly notify the Colorado Department of Public Health and Environment -Water Quality Control
Division, downstream water users, or other appropriate agencies. The release of any chemical, oil,
petroleum product, sewage, etc., which enter waters of the State of Colorado (which include
surface water, ground water, and dry gullies or storm sewers leading to surface water) must be
reported immediately to the Division's emergency spill reporting line at (877) 518-5608. All
spills that will require cleanup, even if the spill is minor and does not need to be reported to the
state, should still be reported to the City of Fort Collins.
Stormwater Management Plan 10
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While not expected with this project, it will be the responsibility of the Contractor to designate a
fueling area and take the necessary precautions to ensure that no stormwater pollution occurs in the
event that a fueling area is needed. Fueling areas shall be located a minimum 100 feet from all
drainage courses. A 12-inch high compacted earthen ridge capable of retaining potential spills
shall enclose fueling areas. Other secondary containment devices can be used instead of the
earthen ridge. The area shall be covered with a non-porous lining to prevent soil contamination.
Printed instructions for cleanup procedures shall be posted in the fueling area and appropriate fuel
absorbents shall be available along with containers for used absorbents within the fueling area.
3.7 Dedicated Concrete or Asphalt Batch Plant
There are not any dedicated concrete or asphalt batch plants anticipated with this project. In the
event that a plant is needed, the Contractor should be aware that additional permitting will be
required. In particular, an Air Pollutant Emission Notice (APEN) will need to be obtained from
CDPHE.
3.8 Vehicle Tracking Control
In addition to the vehicle tracking pads discussed previously, additional measures can be taken to
minimize and control sediment discharges from the site due to vehicle tracking. These measures
can include fencing around the site to control access points. Regular street sweeping can also be
used to minimize the transmission of sediment from the site due to vehicles leaving the site. The
use of gravel parking areas and wash racks can also be implemented to ensure minimal vehicle
tracking from the site. Minimizing or limiting the number of vehicles accessing the site by providing
designated delivery areas, or by restricting deliveries when the site is muddy, is also encouraged.
3.9 Waste Management and Disposal
11 will be the responsibility of the Contractor to designate a concrete truck chute washout area and
to clearly identify that area. Detailed information about the design and maintenance of the Concrete
Washout can be found under the Structural Practices section of this report. At no time should
untreated wash water be allowed to discharge from the site or to enter a storm drain system or
stream. Upon completion of construction activities the concrete washout material shall be removed
and properly disposed of prior to the area being restored.
Any waste material that currently exists on the site or that is generated by construction will be
disposed of in such a manner as to not cause pollutants in stormwater discharges. If waste is to be
stored on-site, it shall be in an area located a minimum of 100 feet from all drainage courses.
Whenever waste is not stored in a non-porous container, it shall be in an area enclosed by a 12-
inch high compacted earthen ridge or some other approved secondary containment device. The area
shall be covered with a non-porous lining to prevent soil contamination. Whenever precipitation is
predicted, the waste shall be covered with a non-porous cover, anchored on all sides to prevent its
removal by wind, in order to prevent precipitation from leaching out potential pollutants from the
waste. On-site waste disposal practices, such as dumpsters, should be covered or otherwise
contained as to prevent dispersion of waste materials from wind. It shall also be the responsibility
of the Contractor to maintain a clean jobsite as to prevent dispersion of waste material and potential
pollutants into adjacent properties or waterways.
The location of, and protective measures for, temporary restroom facilities shall be the responsibility
of the SWMP Administrator.
Stormwater Management Plan 11
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3.10 Groundwater and Stormwater Dewatering
The BMPs selected for construction dewatering vary depending on the site-specific features, such as
soils, topography, discharge quantities, and discharge location. Typically, dewatering involves
pumping water from an inundated area to a BMP, prior to the water being released downstream
into a receiving waterway, sediment basin, or well-vegetated area. Acceptable BMPs included
discharging water into a sediment trap or basin, using a dewatering filter bag, or using a series of
sediment logs. A settlement tank or an active treatment system can also be utilized. Another
commonly used method to handle the pumped water is the "sprinkler method," which involves
applying the water to vegetated areas through a perforated discharge hose. Dispersal from a water
truck for dust control can also be used to disperse the pumped water.
Stormwater Management Pfan 12
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Final Stabilization and Long-Term Stormwater Management
Final Stabilization
All disturbed areas will be seeded, crimped and mulched. Soil amendments; such as compost,
peat, aged manure, or other similar materials, shall also be utilized. As defined by the Colorado
Department of Public Health and Environment in the General Permit Application for Stormwater
Discharges, "Final stabilization is reached when all soil disturbing activities at the site have been
completed, and uniform vegetative cover has been established with a density of at least 70 percent
of pre-disturbance levels or equivalent permanent, physical erosion reduction methods have been
employed."
4.2 Long-Term Stormwater Management
The primary method of long-term stormwater management will be the use of a concrete outlet
structure and a water quality pond. The outlet structure shall be designed in a manner that allows
smaller, more frequent rainfall events to be detained and released over an extended amount of time.
This extended detention allows suspended sediment and pollutants to settle from the water prior to
entering drainage facilities downstream of the site.
In addition to the water quality pond, riprap will be placed at the outlets of all storm sewer pipes,
curb cuts, drainage pans, and similar concentrated discharge points in order to prevent erosion. All
disturbed areas will receive permanent paving or will be vegetated per the Landscape Plan. All
stormwater runoff from paved surfaces and rooftops is released through a vegetated swale prior to
reaching the water quality pond. Therefore, the disconnection of impervious areas combined with
the detention pond design, offer significant water quality enhancement, and will serve the long-term
stormwater management goals for this project.
Stormwater Management Plan 13
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5.0 Inspection, Maintenance and Record Keeping
5.1 BMP Inspection
All temporary erosion control facilities shall be inspected at a minimum of once every two (2) weeks
and after each significant storm event or snowmelt. Repairs or reconstruction of BMPs, as
necessary, shall occur as soon as possible in order to ensure the continued performance of their
intended function. It is the responsibility of the SWMP Administrator to conduct bi-weekly
inspections, maintain BMPs if needed, to keep records of site conditions and inspections, and to
update the SWMP as necessary.
The construction site perimeter, disturbed areas, all applicable/installed erosion and sediment
control measures, and areas used for material storage that are exposed to precipitation shall be
inspected for evidence of, or the potential for, pollutants entering the drainage system. Erosion and
sediment control measures identified in the SWMP shall be observed to ensure that they are
operating correctly. Particular attention should be paid to areas that have a significant potential for
stormwater pollution, such as demolition areas, concrete washout locations, and vehicle entries to
the site. The inspection must be documented to ensure compliance with the permit requirements.
5.2 BMP Maintenance
Any BM P's not operating in accordance with the SWMP must be addressed as soon as possible,
immediately in most cases, to prevent the discharge of pollutants. If modifications are necessary,
such modifications shall be documented so that the SWMP accurately reflects on-site conditions.
The SWMP needs to accurately represent field conditions at all times.
Uncontrolled releases of mud, muddy water, or measurable amounts of sediment found off-site will
be recorded with a brief explanation of the measures taken to clean-up the sediment that has left
the site, as well as the measures taken to prevent future releases. This record shall be made
available to the appropriate public agencies (Colorado Department of Public Health and
Environment, Water Quality Control Division; Environmental Protection Agency; City of Fort Collins;
etc.) upon request.
Preventative maintenance of all temporary and permanent erosion control BMPs shall be provided
in order to ensure the continued performance of their intended function. Temporary erosion control
measures are to be removed after the site has been sufficiently stabilized as determined by the City
of Fort Collins. Maintenance activities and actions to correct problems shall be noted and recorded
during inspections.
Inspection and maintenance procedures specific to each BMP identified with this SWMP are
discussed in Section 3. Details have also been included with Appendix B.
5.3 Record Keeping
Documentation of site inspections must be maintained. The following items are to be recorded and
kept with the SWMP:
• Date of Inspection
• Name(s) and title(s) of personnel making the inspection
• Location(s) of sediment discharges or other pollutants from the site
• Location(s) of BMP's that need to be maintained
• Location(s) of BM P's that failed to operate as designed or proved inadequate
• Locations(s) where additional BM P's are needed that were not in place at the time of inspection
• Deviations from the minimum inspection schedule
• Descriptions of corrective action taken to remedy deficiencies that have been identified
Stormwater Management Plan 14
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• The report shall contain a signed statement indicating the site is in compliance with the permit to the
best of the signer's knowledge and belief after corrective actions have been taken.
Provided within Appendix D of this SWMP is an Example Inspection Log to aid in the record
keeping of BMP inspections and maintenance. Photographs, field notebooks, drawings and maps
should be included when appropriate.
In addition to the Inspection Log, records should be kept documenting:
• BMP maintenance and operation
• Stormwater contamination
• Contacts with suppliers
• Notes on the need for and performance of preventive maintenance and other repairs
• Implementation of specific items in the SWMP
• Training events (given or attended)
• Events involving materials handling and storage
• Contacts with regulatory agencies and personnel
• Notes of employee activities, contact, notifications, etc.
Records of spills, leaks, or overflows that result in the discharge of pollutants must be documented
and maintained. A record of other spills that are responded to, even if they do not result in a
discharge of pollutants, should be made. Information that should be recorded for all occurrences
includes the time and date, weather conditions, reasons for the spill, etc. Some spills may need to
be reported to authorities immediately. Specifically, a release of any chemical, oil, petroleum
product, sewage, etc., which may enter waters of the State of Colorado (which include surface
water, ground water and dry gullies or storm sewers leading to surface water) must be reported to
the CDPHE.
The Stormwater Management Plan is intended to be a "living document" where the SWMP
Administrator can hand write the location of BMPs as they are installed to appropriately reflect the
current site conditions.
This Stormwater Management Plan (both the text and map} is not a static document. It
is a dynamic device intended to be kept current and logged as construction takes place.
It shall be the responsibility of the SWM P Administrator and/or the permit holder (or
applicant thereof) to ensure the plan is properly maintained and followed. Diligent
administration is critical, including processing the Notice to Proceed and noting on the
Stormwater Management Plan the dates that various construction activities occur and
respective BM Ps are installed and/or removed.
Stormwater Management Plan 15
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6.0 Additional SWMP and BMP Resources
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual -Volume 3 "Best Management Practices"
Colorado Department of Transportation
Erosion Control and Stormwater Quality Guide
BMP Field Academy
EPA Menu of BMP's
Construction Site Storm Water Runoff Control
International Stormwater Best Management (BMP) Database
Rocky Mountain Education Center
Rocky Mountain Education Center
Red Rocks Community College, Lakewood
Keep It Clean Partnership
Boulder
Stormwater Management Plan 16
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River District Block One Mixed Use SWMP
References
1. Final Drainage Drainage and Erosion Control Report, River District Block One Mixed Use,
Northern Engineering Services, May 1, 2013 (NES Project No. 685-002).
2. Soil Resource Report for Larimer County Area, Colorado, Natural Resources Conservation
Service, United States Department of Agriculture.
3. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control
District, Water Resources Publications, LLC., Denver, Colorado, Updated November 2010.
4. Subsurface Exploration Report, 418 Linden Street, October 25, 2011, Earth Engineering
Consultants, Inc.
Stormwater Management Plan 17
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16'
MATCH PROPOSED
GRADE (TYP.)
TRANSITION EXISTING
<(
TYPE M RIPRAP
PROPOSED OUTLET
STRUCTURE
B
ro PONO INTO SEDIMENT TRAP
FLOW
MATCH PROPOSED <(
GRADE (TYP.)
PLAN VIEW
8' MIN.
1' MIN. •
·, __ ');.\
SECTION A-A
L PROPOSED POND 1' MIN.
PROPOSED POND
BOTTOM
PROPOSED SEDIMENT
TRAP
PROPOSED OUTLET
STRUCTURE
PROPOSED
1 D" ROCK SOCK
PROPOSED 10n
ROCK SOCK
..
.. BOTTOM _C -<·.;_ "1,t ---------
SECTION B-B PROPOSED SEDIMENT ~
TRAP ~~
E9 SEDIMENT TRAP
NOT TO SCALE
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STORM WATER MANAGEMENT PLAN
INSPECTION TABLE
BMP Name/ Desc. Date Erosion Control Measures Effective
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes(w/Rev)
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
Yes __ No __ Yes (w/Rev) -
_Yes __ No __ Yes(w/Rev)
Yes __ No __ Yes (w/Rev) -
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
Yes __ No __ Yes (w/Rev) -
_Yes __ No __ Yes(w/Rev)
_Yes __ No __ Yes(w/Rev)
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
Yes __ No __ Yes (w/Rev) -
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
_Yes __ No __ Yes (w/Rev)
Yes __ No __ Yes (w/Rev) -
Yes __ No __ Yes (w/Rev) -
_Yes __ No __ Yes(w/Rev)
Brief Revision Description
1
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STORM WATER MANAGEMENT PLAN
INSPECTION TABLE
BMP Name/ Desc. Date Erosion Control Measures Effective
Yes --No --
Yes (w/Rev) -
Yes No Yes (w/Rev)
--- --
Yes No Yes (w/Rev) -----
Yes No Yes (w/Rev) -----
Yes No Yes (w/Rev) -----
Yes No Yes (w/Rev) --- --
Yes No Yes (w/Rev) -----
Yes No Yes (w/Rev) --- --
Yes No Yes (w/Rev) --- --
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes (w/Rev)
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes (w/Rev)
Yes No Yes (w/Rev) --- --
Yes No Yes (w/Rev) --- --
Yes No Yes (w/Rev) -----
Yes No Yes (w/Rev) --- --
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes(w/Rev)
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
Brief Revision Description
2
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STORM WATER MANAGEMENT PLAN
INSPECTION TABLE
BMP Name/ Desc. Date Erosion Control Measures Effective
Yes No Yes (w/Rev) --- --
_ Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
Yes No Yes (w/Rev) -----
Yes No Yes (w/Rev) --- --
_Yes __ No __ · Yes(w/Rev)
_Yes __ No __ Yes(w/Rev)
Yes No Yes (w/Rev) -----
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes(w/Rev)
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
_Yes __ No __ Yes (w/Rev)
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
Yes No Yes (w/Rev) --- --
_Yes __ No __ Yes(w/Rev)
_Yes __ No __ Yes (w/Rev)
_Yes __ No __ Yes(w/Rev)
Brief Revision Description
3
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NorthernEngineering.com // 970.221.41 S8
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•
•
Construction BMPs
•✓"--,-.,,.,' . __ ,,,;
" ~ ~~ --~-' ~;, ·. . . '
Obtain Stormwater Construction Permits
(State and Local)
.. Obtaiit OtherReleva~t Permits
(e0g., 404,' Floo_dplain, ,I>ewatering), ... ,, \., ' ·/ .. _ .
, . Construction Phase .
Representative -Phas'es:
, C'learin~ and Gn1blling ·
• _Rough Grading
11 R03d COns!ru~tion
• Utility and Infrastructure Installatio11
• : Vertical ~onstructi6~ .(Bulldings), ·
Final Grading
' '
Management Practices:
•
Phase·COnst;UdioQ. A.-c-tiviti.es to Mi~imiie
Disturbed Area at.a Given Time
Sequence Cont~uction within Phases to Ave.!,d l
Id.le Distud,ed Areas ·,, . ,· . .. . . . . ,. . . . j
Instali, insj,e~t ~n_d Proafovefy Mai/ltaill BMP~'. j
Ap~rop,rjat~for ~~chlhas~.ofConst~~~-ti~n , j
Mamtam and ·Update SWMP as Construc!Jon', ,,.,
Progre_sses ,·, _/ ~;_ ~-·, ·_ ·:. · __ -: :<~ /'" :~:-<<'-,:\'~ -I
, • ·. Final Stabilization
' . . '
~ ' ' '
November 2010
Figure 7-2. Construction Stormwater Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
7-13
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Construction BMPs
7-14
Table 7-2. Overview of Construction BMPs
Functions Erosion Sediment
Control Control
.
Erosion Control BMPs
Surface Roughening Yes No
Temporary/Permanent Seeding Yes No
Soil Binders Yes No
Mulching Yes Moderate
Compost Blankets and Filter Berms Yes Moderate
Rolled Erosion Control Products Yes No
Temporary Slope Drains Yes No
Temporary Outlet Protection Yes Moderate
Rough Cut S tree! Control Yes Moderate
Earth Dikes/ Drainage Swales Yes Moderate
Terracing Yes Moderate
Check Daim Yes Moderate
Streambank Stabilization Yes No
Wind Erosion/ Dust Control Yes No
::.:.'.~,; ,.'~ 'ii'-'.,;:\> "'· ~it·.
.. , ; , . •.. .. . i'.'-,,, ,,,,i, -~, ~' .
Silt Fence No Yes
Sediment Control Log Moderate Yes
Straw Bale Barrier No Moderate
Brush Barrier Moderate Moderate
Rock Sock (perimeter control) No Yes
Inlet Protection (various forms) No Yes
Sediment Basins No Yes
Sediment Trap. No Yes
Vegetatiw Buffers Moderate Yes
Chemical Treatment Moderate Yes -··,}.·•· •· .. .. · ..
Concrete Washout Area No No
Stockpile Management Yes Yes
Good Houskeeping (multiple practices) No No
W"</W· '"C~'f"t-f'-"fa~%'•~%D.\;;0,it#f$j¢hW~l.~~1~·~1f,jJMY,:f:#W'"'¢"'"","fJ,-. · :,_: ( '. . s"ifetMJthf·--e·minf?31l(h0th"Cls· CcifiCr-Prl1ttti'2Cltf'rJ:_;:::~,~ . ½ ,_ -: >. ·. · ,-," ,_ ., . .,Jt ,,. ,, ·,·, K:'-i'." .\\.,::,,>·:·.•/•\,,"'.'M _,.," (',,1--'<. 'P, . .,t,_c<r-.-o-.: F\, ·-•\"f'.'i!C.••,,_,,,_, •._-, J ,-<,<. <' , · · .. \· . . .
Construction Phasing Moderate Moderate
Protection of Existing Vegetation Yes Moderate
Construction Fence No No
Vehicle Tracking Control Moderate Yes
Stabilized Construction Roadmly Yes Moderate
Stabilized Staging Area Yes Moderate
Street S»eeping / Vacuuming No Yes
Temporary Diversion Channel Yes No
Dewatering Operations Moderate Yes
Temporary Stream Crossing Yes Yes
Temporary Batch Plants No No
Paving and Grinding Operations No No
Urban Drainage and Flood Control District
Urban Storm Drainage Criieria Manual Volume 3
. · ..
Construction BMPs
Site/Mate rial
Management
No
No
Moderate
No
No
No
No
No
No
No
No
No
No
Moderate
• .
No
No
No
No
No
No
No
No
Yes
No ' .. . . ·•r .. < .•
Yes
Yes
Yes
.. Ti." ;1:
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Yes
No
Yes
Yes
November 20 I 0
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Surface Roughening (SR)
Description
Surface roughening is an erosion control
practice that involves tracking,
scarifying, imprinting, or tilling a
disturbed area to provide temporary
stabilization of disturbed areas. Surface
roughening creates variations in the soil
surface that help to minimize wind and
water erosion. Depending on the
technique used, surface roughening may
also help establish conditions favorable
to establishment of vegetation.
Appropriate Uses
EC-1
Surface roughening can be used to Photograph SR-1. Surface roughening via imprinting for temporary
provide temporary stabilization of stabilization.
disturbed areas, such as when
revegetation cannot be immediately established due to seasonal planting limitations. Surface roughening
is not a stand-alone BMP, and should be used in conjunction with other erosion and sediment controls.
Surface roughening is oftenjmplemented in conjunction with grading and is typically performed using
heavy construction equipment to track the surface. Be aware that tracking with heavy equipment will also
compact soils, which is not desirable in areas that will be revegetated. Scarifying, tilling, or ripping are
better surface roughening techniques in locations where revegetation is planned. Roughening is not
effective in very sandy soils and cannot be effectively performed in rocky soil.
Design and Installation
Typical design details for surfacing roughening on steep and mild slopes are provided in Details SR-I and
SR-2, respectively.
Surface roughening should be performed either after final grading or to temporarily stabilize an area
during active construction that may be inactive for a short time period. Surface roughening should create
depressions 2 to 6 inches deep and approximately 6 inches apart. The surface of exposed soil can be
roughened by a number of techniques and equipment. Horizontal grooves (running parallel to the
contours of the land) can be made using tracks from equipment treads, stair-step grading, ripping, or
tilling.
Fill slopes can be constructed with a roughened surface. Cut slopes that have been smooth graded can be
roughened as a subsequent operation. Roughening should follow along the contours of the slope. The
tracks left by truck mounted equipment working perpendicular
to the contour can leave acceptable horizontal depressions;
however, the equipment will also compact the soil.
Surface Roughening
November 2010
: Fii~~tioiis;:~• ;.5{t•:·:.·-",t.:••'.
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
'.t ,.i. ·'.:. ·;:"::<:_:'·:~~:
Yes
No
No
SR-I
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EC-1 Surface Roughening (SR)
Maintenance and Removal
Care should be taken not to drive vehicles or equipment over areas that have been surface roughened.
Tire tracks will smooth the roughened surface and may cause runoff to collect into rills and gullies.
Because surface roughening is only a temporary control, additional treatments may be necessary to
maintain the soil surface in a roughened condition .
Areas should be inspected for signs of erosion. Surface roughening is a temporary measure, and will not
provide long-term erosion control.
SR-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Surface Roughening (SR)
November 2010
------L 4" TO 6"
DEEP
TRACKING OR
IMPRINTING
FURROWS 2" TO 4" DEEP
WITH 6" MAXIMUM SPACING
PARALLEL TO CONTOURS
SR-1. SURFACE ROUGHENING
fOR STEEP SLOPES (3:1 OR STEEPER)
ROUGHENED ROWS SHALL BE 4" TO 6"
DEEP WITH 6" MAXIMUM SPACING PARALLEL
TO CONTOURS
SR-2. SURFACE ROUGHENING
FOR LOW SLOPES (LESS THAN 3: 1)
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
EC-1
G
SR-3
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EC-1
SR-4
Surface Roughening (SR)
SURFACE ROIIGHENING INSTAI LATiON NOTES
1. SEE PLAN VIEW FOR;
-LOCATION(S) OF SURFACE ROUGHENING.
2. SURFACE ROUGHENING SHALL BE PROVIDED PROMPTLY AFTER COMPLETION OF FINISHED
GRADING (FOR AREAS NOT RECEIVING TOPSOIL) OR PRIOR TO TOPSOIL PLACEMENT OR ANY
FORECASTED RAIN EVENT.
3. AREAS WHERE BUILDING FOUNDATIONS, PAVEMENT, OR SOD WILL BE PLACED WITHOUT
DELAY IN THE CONSTRUCTION SEQUENCE, SURFACE ROUGHENING IS NOT REQUIRED.
4. DISTURBED SURFACES SHALL BE ROUGHENED USING RIPPING OR TILLING EQUIPMENT ON
THE CONTOUR OR TRACKING UP AND DOWN A SLOPE USING EQUIPMENT TREADS.
5. A FARMING DISK SHALL NOT BE USED FOR SURFACE ROUGHENING.
SURFACE ROUGHENING MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACE UPON DISCOVERY OF THE FAILURE.
4. VEHICLES AND EQUIPMENT SHALL NOT BE DRNEN OVER AREAS THAT HAVE BEEN SURFACE
ROUGHENED.
5. IN NON-TURF GRASS FINISHED AREAS, SEEDING AND MULCHING SHALL TAKE PLACE
DIRECTLY OVER SURFACE ROUGHENED AREAS WITHOUT FIRST SMOOTHING OUT THE SURFACE.
6. IN AREAS NOT SEEDED AND MULCHED AIFTER SURFACE ROUGHENING, SURFACES SHALL BE
RE-ROUGHENED AS NECESSARY TO MAINTAIN GROOVE DEPTH AND SMOOTH OVER RILL
EROSION.
(OET>JLS AO.APTEO FROM TOWN OF PAAKER, COLORADO, NOT AVAILA81.E IN AUTOCAO)
~ MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Temporary and Permanent Seeding {TS/PS) EC-2
Description
Tcmpormy seeding can be used to
stabilize disturbed areas that will be
inactive for an extended period.
Permanent seeding should be used to
stabilize areas at final grade that will not
be otherwise stabilized. Effective seeding
includes preparation of a seedbed,
selection of an appropriate seed mixture,
proper planting techniques, and protection
of the seeded area with mulch, gcotextiles,
or other appropriate measures.
Appropriate Uses
When the soil surface is disturbed and
will remain inactive for an extended
period (typically 30 days or longer),
Photograph TS/PS -1. Equipment used to drill seed. Photo courtesy of
Douglas County.
proactive stabilization measures should be implemented. If the inactive period is short-lived (on the order
of two weeks), techniques such as surface roughening may be appropriate. For longer periods of
inactivity, temporary seeding and mulching can provide effective erosion control. Permanent seeding
should be used on finished areas that have not been otherwise stabilized.
Typically, local governments have their own seed mixes and timelines for seeding. Check jurisdictional
requirements for seeding and temporary stabilization.
Design and Installation
Effective seeding requires proper seedbed preparation, selection of an appropriate seed mixture, use of
appropriate seeding equipment to ensure proper coverage and density, and protection with mulch or fabric
until plants are established.
The USDCM Volume 2 Revegetation Chapter contains detailed seed mix, soil preparations, and seeding
and mulching recommendations that may be referenced to supplement this Fact Sheet.
Drill seeding is the preferred seeding method. Hydroseeding is not recommended except in areas where
steep slopes prevent use of drill seeding equipment, and even in these instances it is preferable to hand
seed and mulch. Some jurisdictions do not allow hydroseeding or hydromulching.
Seedbed Preparation
Prior to seeding, ensure that areas to be revegetated have
soil conditions capable of supporting vegetation. Overlot
grading can result in loss of topsoil, resulting in poor quality
subsoils at the ground surface that have low nutrient value,
little organic matter content, few soil microorganisms,
rooting restrictions, and conditions less conducive to
infiltration of precipitation. As a result, it is typically
necessary to provide stockpiled topsoil, compost, or other
Temporary and Permanent
Functions
Erosion Control
Sediment Control
Site/Material Management
November 20IO Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Seeding
Yes
No
No
TS/PS-I
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EC-2 Temporary and Permanent Seeding (TS/PS)
soil amendments and rototill them into the soil to a depth of6 inches or more.
Topsoil should be salvaged during grading operations for use and spread on areas to be revegetated later.
Topsoil should be viewed as an important resource to be utilized for vegetation establishment, due to its
water-holding capacity, structure, texture, organic matter content, biological activity, and nutrient content.
The rooting depth of most native grasses in the semi-arid Denver metropolitan area is 6 to 18 inches. At a
minimum, the upper 6 inches of topsoil should be stripped, stockpiled, and ultimately respread across
areas that will be revegetatcd.
Where topsoil is not available, subsoils should be amended to provide an appropriate plant-growth
medium. Organic matter, such as well digested compost, can be added to improve soil characteristics
conducive to plant growth. Other treatments can be used to adjust soil pH conditions when needed. Soil
testing, which is typically inexpensive, should be completed to determine and optimize the types and
amounts of amendments that are required.
If the disturbed ground surface is compacted, rip or rototill the surface prior to placing topsoil. If adding
compost to the existing soil surface, rototilling is necessary. Surface roughening will assist in placement
of a stable topsoil layer on steeper slopes, and allow infiltration and root penetration to greater depth.
Prior to seeding, the soil.surface should be rough and the seedbed should be firm, but neither too loose
nor compacted. The upper layer of soil should be in a condition suitable for seeding at the proper depth
and conducive to plant growth. Seed-to-soil contact is the key to good germination.
Seed M!:\'. for Temporary Vegetation
To provide temporary vegetative cover on disturbed areas which will not be paved, built upon, or fully
landscaped or worked for an extended period (typically 30 days or more), plant an annual grass
appropriate for the time of planting and mulch the planted areas. Annual grasses suitable for the Denver
metropolitan area are listed in Table TS/PS-I. These are to be considered only as general
recommendations when specific design guidance for a particular site is not available. Local governments
typically specify seed mixes appropriate for their jurisdiction.
Seed Mix for Permanent Revegetation
To provide vegetative cover on disturbed areas that have reached final grade, a perennial grass mix should
be established. Permanent seeding should be performed promptly (typically within 14 days) after
reaching final grade. Each site will have different characteristics and a landscape professional or the local
jurisdiction should be contacted to determine the· most suitable seed mix for a specific site. In lieu of a
specific recommendation, one of the perennial grass mixes appropriate for site conditions and growth
season listed in Table TS/PS-2 can be used. The pure live seed (PLS) rates of application recommended
in these tables are considered to be absolute minimum rates for seed applied using proper drill-seeding
equipment.
If desired for wildlife habitat or landscape diversity, shrubs such as rubber rabbit brush (Chrysothamnus
nauseosus), fourwing saltbush (Atriplex canescens) and skunkbrush sumac (Rhus trilobata) could be
added to the upland seedmixes at 0.25, 0.5 and I pound PLS/acre, respectively. In riparian zones,
planting root stock of such species as American plum (Pru nus americana), woods rose (Rosa woods ii),
plains cottonwood (Populus sargentii), and willow (Populus spp.) may be considered. On non-topsoiled
upland sites, a legume such as Ladak alfalfa at I pound PLS/acre can be included as a source of nitrogen
for perennial grasses.
TS/PS-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Temporary and Permanent Seeding (TS/PS) EC-2
Seeding dates for the highest success probability of perennial species along the Front Range are generally
in the spring from April through early May and in the fall after the first of September until the ground
freezes. If the area is irrigated, seeding may occur in summer months, as well. See Table TS/PS-3 for
appropriate seeding dates.
Table TS/PS-1. Minimum Drill Seeding Rates for Various Temporary Annual Grasses
Pounds of Planting
Species' Growth Pure Live Seed Depth
h ' (Common name) Season (PLS)/acre (inches)
I. Oats Cool 35 -50 1 - 2
2. Spring wheat Cool 25 -35 1 - 2
3. Spring barley Cool 25 -35 1 - 2
4. Annual ryegrass Cool IO -15 ½
5. Millet Warm 3 -15 ½-¾
6. Sudangrass Warm 5-10 ½-¼
7. Sorghum Warm 5-10 ½-¾
8. Winter wheat Cool 20-35 1 - 2
9. Winter barley Cool 20-35 1 - 2
10. Winter rye Cool 20-35 I -2
1 I. Triticale Cool 25-40 I -2
' Successful seeding of annual grass resulting in adequate plant growth will
usually produce enough dead-plant residue to provide protection from
wind and water erosion for an additional year. This assumes that the cover
is not disturbed or mowed closer than 8 inches.
Hydraulic seeding may be substituted for drilling only where slopes are
steeper than 3:1 or where access limitations exist. When hydraulic
seeding is used, hydraulic mulching should be applied as a separate
operation, when practical, to prevent the seeds from being encapsulated in
the mulch.
b See Table TS/PS-3 for seeding dates. Irrigation, if consistently applied,
may extend the use of cool season species during the summer months.
' Seeding rates should be doubled if seed is broadcast, or increased by 50
percent if done using a Brillion Drill or by hydraulic seeding.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
TS/PS-3
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EC-2 Temporary and Permanent Seeding (TS/PS)
Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses
Common ' Bolanical Growth Growth
Name Name Seasonb Form
Alakali Soil Seed Mix
Alkali sacaton Sporobolus airoides Cool Bunch
Basin wildrye E(rmus cinereus Cool Bunch
Sedar streambank whcatgrass Agropyron riparium 'Sodar' Cool Sod
Jose tall whcatgrass Agropyron elongatum 'Jose' Cool Bunch
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod
Total
Fertile Loamy Soil Seed Mix
Ephriam crested wheatgrass Agropyron cristatum Cool Sod 'Ephriam'
Dural hard fescue Festuca ovina 'duriusc11/a' Cool Bunch
Lincoln smooth brome Bromus inermis leyss Cool Sod 'Lincoln'
Sodar streambank wheatgrass Agropyron riparium 'Sadar' Cool Sod
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod
Total
High Water Table Soil Seed Mix
Meadow foxtail
Rcdtop
Reed canarygrass
Lincoln smooth brome
Pathfinder switchgrass
Alkar tall wheatgrass
Total
Transition Turf Seed Mixc
Ruebens Canadian bluegrass
Dural hard fescuc
Citation perennial ryegrass
Lincoln smooth brome
Total
TS/PS-4
Alopecurus pratensis Cool Sod
Agrostis alba Wann Open sod
Phalaris arundinacea Cool Sod
Bromus inermis leyss Cool Sod 'Lincoln'
Panicum virgatum Warm Sod 'Pathfinder'
Agropyron elongalum Cool Bunch 'Alkar'
Poa compressa 'Ruebens' Cool Sod
Festuca ovina 'duriuscula' Cool Bunch
Lolium perenne 'Cilation' Cool Sod
Bromus inermis leyss Cool Sod 'Lincoln'
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Seeds/ Pounds of
Pound PLS/acre
1,750,000 0.25
165,000 2.5
170,000 2.5
79,000 7.0
110,000 5.5
17.75
175,000 2.0
565,000 1.0
130,000 3.0
170,000 2.5
110,000 7.0
15.5
..
900,000 0.5
5,000,000 0.25
68,000 0.5
130,000 3.0
389,000 1.0
79,000 5.5
10.75
2,500,000 0.5
565,000 1.0
247,000 3.0
130,000 3.0
7.5
November 20 IO
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Temporary and Permanent Seeding (TS/PS) EC-2
Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses (cont.)
Common Botanical Growth Growth Seeds/ Pounds of
Name Name Seasonb Form Pound PLS/acre
Sandy Soil Seed Mix
Blue grama Bouteloua graci/;s Warm Sod-forming 825,000 0.5 bunchgrass
Camper little blucstcm Schizachyrium scoparium Warm Bunch 240,000 1.0 'Camper'
Prairie sandreed Calamovi(fa longffolia Warm Open sod 274,000 1.0
Sand dropsecd Sporobolus cryptandrus Cool Bunch 5,298,000 0.25
Vaughn sideoats grama Bouteloua curtipendula Wann Sod 191,000 2.0 'Vaughn'
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 10.25
Heavy Clay, Rocky Foothill Seed Mix
Ephriam crested wheatgrassct Agropyron cristatum Cool Sod 175,000 1.5 'Ephriam'
Oahe Intermediate wheatgrass Agropyron intermedium Cool Sod 115,000 5.5 'Oahe'
Vaughn sideoats gramae Bouteloua curtipendula Warm Sod 191,000 2.0 'Vaughn'
Lincoln smooth brome Bromus inermis leyss Cool Sod 130,000 3.0 'Lincoln'
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 17.5
' All of the above seeding mixes and rates are based on drill seeding followed by crimped hay or straw mulch. These rates
should be doubled if seed is broadcast and should be increased by 50 percent if the seeding is done using a Brillion Drill or is
applied through hydraulic seeding. Hydraulic seeding may be substituted for drilling only where slopes are steeper than 3: I.
If hydraulic seeding is used, hydraulic mulching should be done as a separate operation.
b See Table TS/PS-3 for seeding dates.
' If site is to be irrigated, the transition turf seed rates should be doubled.
d Crested wheatgrass should not be used on slopes steeper than 6H to 1 V.
' Can substitute 0.5 lbs PLS of blue grama for the 2.0 lbs PLS of Vaughn sideoats grama.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
TS/PS-5
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EC-2 Temporary and Permanent Seeding (TS/PS)
Table TS/PS-3. Seeding Dates for Annual and Perennial Grasses
Annual Grasses Perennial Grasses
(Numbers in table reference
species in Table TS/PS-1)
Seeding Dates Warm Cool Warm Cool
January I-March 15 ✓ ✓
March 16-April 30 4 1,2,3 ✓ ✓
May I-May 15 4 ✓
May 16-June 30 4,5,6,7
July I-July 15 5,6,7
July 16-August 31
September I-September 30 8,9,10,11
October I-December 31 ✓ ✓
Mulch
Cover seeded areas with mulch or an appropriate rolled erosion control product to promote establishment
of vegetation. Anchor mulch by crimping, netting or use ofa non-toxic tackifier. See the Mulching BMP
Fact Sheet for additional guidance.
Maintenance and Removal
Monitor and observe seeded areas to identify areas of poor growth or areas that fail to germinate. Reseed
and mulch these areas, as needed.
An area that has been permanently seeded should have a good stand of vegetation within one growing
season if irrigated and within three growing seasons without irrigation in Colorado. Reseed portions of
the site that fail to germinate or remain bare after the first growing season.
Seeded areas may require irrigation, particularly during extended dry periods. Targeted weed control may
also be necessary.
P~otect seeded areas from construction equipment and vehicle access.
TS/PS-6 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Soil Binders (SB) EC-3
Description
Soil binders include a broad range of
treatments that can be applied to exposed
soils for temporary stabilization to reduce
wind and water erosion. Soil binders may
be applied alone or as tackifiers in
conjunction with mulching and seeding
applications.
Acknowledgement: This BMP Fact Sheet
has been adapted from the 2003
California Stormwater Quality
Association (CASQA) Stormwater BMP
Handbook: Construction
(www.cabmphandbooks.com).
Appropriate Uses Photograph SB-1. Tackifier being applied to provide temporary soil
stabilization. Photo courtesy of Douglas County.
Soil binders can be used for short-term, temporary stabilization of soils on both mild and steep slopes.
Soil binders are often used in areas where work has temporarily stopped, but is expected to resume before
revegetation can become established. Binders are also useful on stockpiled soils or where temporary or
permanent seeding has occurred.
Prior to selecting a soil binder, check with the state and local jurisdiction to ensure that the chemicals
used in the soil binders are allowed. The water quality impacts of some types of soil binders are relatively
unknown and may not be allowed due to concerns about potential environmental impacts. Soil binders
must be environmentally benign (non-toxic to plant and animal life), easy to apply, easy to maintain,
economical, and should not stain paved or painted surfaces.
Soil binders should not be used in vehicle or pedestrian high traffic areas, due to loss in effectiveness
under these conditions.
Site soil type will dictate appropriate soil binders to be used. Be aware that soil binders may not function
effectively on silt or clay soils or highly compacted areas. Check manufacturer's recommendations for
appropriateness with regard to soil conditions. Some binders may not be suitable for areas with existing
vegetation.
Design and Installation
Properties of common soil binders used for erosion control
are provided in Table SB-I. Design and installation
guidance below are provided for general reference. Follow
the manufacturer's instructions for application rates and
procedures.
Soil Binders
Furi.ctioits ~ ; , .• ' .. .
Erosion Control
Sediment Control
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
,, -~, 0 . ·,. ·,: . ..
Yes
No
Moderate
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EC-3 Soil Binders (SB)
Table SB-1. Properties of Soil Binders for Erosion Control (Source: CASQA 2003)
Evaluation Criteria
Resistance to Leaching
Resistance to Abrasion
Longevity
Minimum Curing Time
before Rain
Compatibility with
Existing Vegetation
Mode of Degradation
Specialized Application
Equipment
Liquid/Powder
Surface Crusting
Clean Up
Erosion Control
Application Rate
SB-2
Binder Type
Plant Material Plant Material Polymeric Based Based
(short lived) (long lived) Emulsion Blends
High High Low to Moderate
Moderate Low Moderate to High
Short to Medium Medium Medium to Long
9 to 18 hours I 9 to 24 hours 0 to 24 hours
Good Poor Poor
Photodegradable/
Biodegradable Biodegradable Chemically
Degradable
Water Truck or Water Truck or Water Truck or
Hydraulic Hydraulic Hydraulic Mulcher
Mulcher Mulcher
Powder Liquid Liquid/Powder
Yes, but Yes, but dissolves on
dissolves on Yes rewetting
rewetting
Water Water Water
Varies Varies Varies
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Cementitious-
Based Binders
Moderate
Moderate to High
Medium
4 to 8 hours
Poor
Photodegradable/
Chemically
Degradable
Water Truck or
Hydraulic Mulcher
Powder
Yes
Water
4,000 to 12,000
lbs/acre Typ.
November 2010
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Soil Binders (SB) EC-3
Factors to consider when selecting a soil binder generally include:
•
•
Suitability to situation: Consider where the soil binder will be applied, if it needs a high resistance
to leaching or abrasion, and whether it needs to be compatible with existing vegetation. Determine
the length of time soil stabilization will be needed, and if the soil binder will be placed in an area
where it will degrade rapidly. In general, slope steepness is not a discriminating factor.
Soil types and surface materials: Fines and moisture content are key properties of surface
materials. Consider a soil binder's ability to penetrate, likelihood of leaching, and ability to form a
surface crust on the surface materials.
• Frequency of application: The frequency of application can be affected by subgrade conditions,
surface type, climate, and maintenance schedule. Frequent applications could lead to high costs.
Application frequency may be minimized if the soil binder has good penetration, low evaporation,
and good longevity. Consider also that frequent application will require frequent equipment clean up.
An overview of major categories of soil binders, corresponding to the types included in Table SB-I
follows.
Plant-Material Based (Short Lived) Binders
•
•
•
Guar: A non-toxic, biodegradable, natural galactomannan-based hydrocolloid treated with dispersant
agents for easy field mixing. It should be mixed with water at the rate of 11 to 15 lbs per 1,000
gallons. Recommended minimum application rates are provided in Table SB-2.
Table SB-2. Application Rates for Guar Soil Stabilizer
Slo le (H:V)
Flat 4:1 3: I 2: I I: I
Application Rate (lb/acre) 40 45 50 60 70
Psyllium: Composed of the finely ground muciloid coating ofplantago seeds that is applied as a wet
slurry to the surface of the soil. It dries to form a firm but rewettable membrane that binds soil
particles together but permits germination and growth of seed. Psyllium requires 12 to 18 hours
drying time. Application rates should be from 80 to 200 lbs/acre, with enough water in solution to
allow for a uniform slurry flow.
Starch: Non-ionic, cold-water soluble (pre-gelatinized) granular cornstarch. The material is mixed
with water and applied at the rate of 150 lb/acre. Approximate drying time is 9 to 12 hours.
Plant-Material Based (Long Lived) Binders
• Pitch and Rosin Emulsion: Generally, a non-ionic pitch and rosin emulsion has a minimum solids
content of 48 percent. The rosin should be a minimum of26 percent of the total solids content. The
soil stabilizer should be a non-corrosive, water dilutable emulsion that upon application cures to a
water insoluble binding and cementing agent. For soil erosion control applications, the emulsion is
diluted and should be applied as follows:
o For clayey soil: 5 parts water to I part emulsion
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SB-3
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EC-3 Soil Binders (SB)
o For sandy soil: IO parts water to I part emulsion
Application can be by water truck or hydraulic seeder with the emulsion and product mixture applied
at the rate specified by the manufacturer.
Polymeric Emulsion Blend Binders
• Acrylic Copolymers and Polymers: Polymeric soil stabilizers should consist of a liquid or solid
polymer or copolymer with an acrylic base that contains a minimum of 55 percent solids. The
polymeric compound should be handled and mixed in a manner that will not cause foaming or should
contain an anti-foaming agent. The polymeric emulsion should not exceed its shelf life or expiration
date; manufacturers should provide the expiration date. Polymeric soil stabilizer should be readily
miscible in water, non-injurious to seed or animal life, non-flammable, should provide surface soil
stabilization for various soil types without inhibiting water infiltration, and should not re-emulsify
when cured. The applied compound should air cure within a maximum of 36 to 48 hours. Liquid
copolymer should be diluted at a rate of 10 parts water to I part polymer and the mixture applied to
soil at a rate of I, 175 gallons/acre.
• Liquid Polymers of Mcthacrylates and Acrylates: This material consists of a tackifier/scalcr that is
a liquid polymer of mcthacrylatcs and acrylates. It is an aqueous I 00 percent acrylic emulsion blend
of 40 percent solids by volume that is free from styrene, acetate, vinyl, ethoxylated surfactants or
silicates. For soil stabilization applications, it is diluted with water in accordance with manufacturer's
recommendations, and applied with a hydraulic seeder at the rate of20 gallons/acre. Drying time is
12 to I 8 hours after application.
• Copolymers of Sodium Aerylates and Acrylamides: These materials are non-toxic, dry powders
that are copolymers of sodium acrylate and acrylamide. They are mixed with water and applied to the
soil surface for erosion control at rates that are determined by slope gradient, as summarized in Table
SB-3.
Table SB-3. Application Rates for Copolymers of Sodium Acrylates and Acrylamides
Slone (H:V
Flat to 5: I 5:lto3:l 2:2to 1:1
Annlication Rate (lb/acre) 3.0 5.0 5.0 10.0 10.0-20.0
• Polyacrylamide and Copolymer of Acrylamide: Linear copolymer polyacrylamide is packaged as
a dry flowable solid. When used as a stand-alone stabilizer, it is diluted at a rate of 11 lb/1,000 gal. of
water and applied at the rate of 5.0 lb/acre.
• Hydrocolloid Polymers: Hydrocolloid Polymers are various combinations of dry flowable
polyacrylamides, copolymers, and hydrocolloid polymers that are mixed with water and applied to the
soil surface at rates of 55 to 60 lb/acre. Drying times are Oto 4 hours.
I Cementitious-Based Binders
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• Gypsum: This formulated gypsum based product readily mixes with water and mulch to form a thin
protective crust on the soil surface. It is composed of high purity gypsum that is ground, calcined and
processed into calcium sulfate hemihydratc with a minimum purity of86 percent. It is mixed in a
hydraulic seeder and applied at rates 4,000 to 12,000 lb/acre. Drying time is 4 to 8 hours.
SB-4 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Soil Binders (SB) EC-3
Installation
After selecting an appropriate soil binder, the untreated soil surface must be prepared before applying the
soil binder. The untreated soil surface must contain sufficient moisture to assist the agent in achieving
unifonn distribution. In general, the following steps should be followed:
• Follow manufacturer's written recommendations for application rates, pre-wetting of application area,
and cleaning of equipment after use.
• Prior to application, roughen embankment and fill areas.
• Consider the drying time for the selected soil binder and apply with sufficient time before anticipated
rainfall. Soil binders should not be applied during or immediately before rainfall.
• A void over spray onto roads, sidewalks, drainage channels, sound walls, existing vegetation, etc.
• Soil binders should not be applied to frozen soil, areas with standing water, under freezing or rainy
conditions, or when the temperature is below 40°F during the curing period.
• More than one treatment is often necessary, although the second treatment may be diluted or have a
lower application rate.
• Generally, soil binders require a minimum curing time of 24 hours before they are fully effective.
Refer to manufacturer's instructions for specific cure time.
• For liquid agents:
o Crown or slope ground to avoid ponding.
o Uniformly pre-wet ground at 0.03 to 0.3 gal/yd2 or according to manufacturer's recommendations.
o Apply solution under pressure. Overlap solution 6 to 12 in.
o Allow treated area to cure for the time recommended by the manufacturer, typically at least 24
hours.
o Apply second treatment before first treatment becomes ineffective, using 50 percent application
rate.
o In low humidity, reactivate chemicals by re-wetting with water at 0.1 to 0.2 gal/yd 2
•
Maintenance and Removal
Soil binders tend to break down due to natural weathering. Weathering rates depend on a variety of site-
specific and product characteristics. Consult the manufacturer for recommended reapplication rates and
reapply the selected soil binder as needed to maintain effectiveness.
Soil binders can fail after heavy rainfall events and may require reapplication. In particular, soil binders
will generally experience spot failures during heavy rainfall events. If runoff penetrates the soil at the top
of a slope treated with a soil binder, it is likely that the runoff will undercut the stabilized soil layer and
discharge at a point further down slope.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SB-5
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EC-3 Soil Binders (SB)
Areas where erosion is evident should be repaired and soil binder or other stabilization reapplied, as
needed. Care should be exercised to minimize the damage to protected areas while making repairs.
Most binders biodcgradc after exposure to sun, oxidation, heat and biological organisms; therefore,
removal of the soil binder is not typically required.
SB-6 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Mulching (MU)
Description
Mulching consists of evenly applying
straw, hay, shredded wood mulch, bark or
compost to disturbed soils and securing
the mulch by crimping, tackifiers, netting
or other measures. Mulching helps reduce
erosion by protecting bare soil from
rainfall impact, increasing infiltration, and
reducing runoff. Although often applied
in conjunction with temporary or
permanent seeding, it can also be used for
temporary stabilization of areas that
cannot be reseeded due to seasonal
constraints.
Mulch can be applied either using
EC-4
standard mechanical dry application
methods or using hydromulching equipment
that hydraulically applies a slurry of water,
wood fiber mulch, and often a tackifier.
Photograph MU-1. An area that was recently seeded, mulched,
and crimped.
Appropriate Uses
Use mulch in conjunction with seeding to help protect the seedbed and stabilize the soil. Mulch can also
be used as a temporary cover on low to mild slopes to help temporarily stabilize disturbed areas where
growing season constraints prevent effective reseeding. Disturbed areas should be properly mulched and
tacked, or seeded, mulched and tacked promptly after final grade is reached (typically within no longer
than 14 days) on portions of the site not otherwise permanently stabilized.
Standard dry mulching is encouraged in most jurisdictions; however, hydromulching may not be allowed
in certain jurisdictions or may not be allowed near waterways.
Do not apply mulch during windy conditions.
Design and Installation
Prior to mulching, surface-roughen areas by rolling with a crimping or punching type roller or by track
walking. Track walking should only be used where other methods are impractical because track walking
with heavy equipment typically compacts the soil.
A variety of mulches can be used effectively at construction
sites, including the following types:
Functiolis; .·
Erosion Control
Mulch
..
Sediment Control
November 2010
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
~
.
Yes
Moderate
No
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■
•
•
•
•
•
•
EC-4 Mulching (MU)
Clean, weed-and seed-free, long-stemmed grass hay (prefen-ed) or cereal grain straw. Hay is prefen-ed
because it is less susceptible to removal by wind. Mulch should be applied evenly at a rate of2 tons per
acre and must be tacked or fastened by an approved method suitable for the type of mulch used. At least
50 percent of the grass hay mulch, by weight, should be 10 inches or more in length.
Grass hay mulch must be anchored and not merely placed on the surface. This can be accomplished
mechanically by crimping or with the aid of tackifiers or nets. Anchoring with a crimping implement is
prefen-ed, and is the recommended method for areas flatter than 3: I. Mechanical crimpers must be
capable of tucking the long mulch fibers into the soil to a depth of 3 inches without cutting them. An
agricultural disk, while not an ideal substitute, may work if the disk blades are dull or blunted and set
vertically; however, the frame may have to be weighted to afford proper soil penetration.
On small areas sheltered from the wind and heavy runoff, spraying a tackifier on the mulch is satisfactory
for holding it in place. For steep slopes and special situations where greater control is needed, erosion
control blankets anchored with stakes should be used instead of mulch.
Hydraulic mulching consists of wood cellulose fibers mixed with water and a tackifying agent and should
be applied at a rate ofno less than 1,500 pounds per acre (1,425 lbs of fibers mixed with at least 75 lbs of
tackifier) with a hydraulic mulcher. For steeper slopes, up to 2000 pounds per acre may be required for
effective hydroseeding. Hydromulch typically requires up to 24 hours to dry; therefore, it should not be
applied immediately prior to inclement weather. Application to roads, waterways and existing vegetation
should be avoided.
Erosion control mats, blankets, or nets are recommended to help stabilize steep slopes (generally 3: I and
steeper) and waterways. Depending on the product, these may be used alone or in conjunction with grass
or straw mulch. Normally, use of these products will be restricted to relatively small areas.
Biodegradable mats made of straw and jute, straw-coconut, coconut fiber, or excelsior can be used instead
of mulch. (See the ECM/fRM BMP for more information.)
Some tackifiers or binders may be used to anchor mulch. Check with the local jurisdiction for allowed
tackifiers. Manufacturer's recommendations should be followed at all times. (See the Soil Binder BMP
for more information on general types oftackifiers.)
Rock can also be used as mulch. It provides protection of exposed soils to wind and water erosion and
allows infiltration of precipitation. An aggregate base course can be spread on disturbed areas for
temporary or permanent stabilization. The rock mulch layer should be thick enough to provide full
coverage of exposed soil on the area it is applied.
Maintenance and Removal
After mulching, the bare ground surface should not be more than 10 percent exposed. Reapply mulch, as
needed, to cover bare areas.
MU-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Compost Blanket and Filter Berm (CB)
Description
A compost blanket is a layer of compost uniformly applied
to the soil in disturbed areas to control erosion, facilitate
revegetation, and retain sediment resulting from sheet-flow
runoff.
A compost filter berm is a dike of compost or a compost
product that is placed perpendicular to runoff to control
erosion in disturbed areas and retain sediment. Compost
berms can be placed at regular intervals to help reduce the
formation ofrill and gully erosion when a compost blanket
is stabilizing a slope.
Appropriate Uses
EC-5
Compost blankets can be used as an alternative to erosion
control blankets and mulching to help stabilize disturbed
areas where sheet flow conditions are present. Compost
blankets should not be used in areas of concentrated flows.
Compost provides an excellent source of nutrients for plant
growth, and should be considered for use in areas that will be
permanently vegetated.
Photograph CB-1. Application of a compost
blanket to a dishlrbed area. Photo courtesy of
Caltrans.
Design and Installation
See Detail CB-1 for design details and notes.
Do not place compost in areas where it can easily be transported into drainage pathways or waterways.
When using a compost blanket on a slope, berms should be installed periodically to reduce the potential
for concentrated flow and rilling. Seeding should be completed before an area is composted or
incorporated into the compost.
Compost quality is an important consideration when selecting compost blankets or berms. Representative
compost quality factors include pH, salinity, moisture content, organic matter content, stability (maturity),
and physical contaminants. The compost should meet all local, state, and federal quality requirements.
Biosolids compost must meet the Standards for Class A biosolids outlined in 40 CFR Part 503. The U.S.
Composting Council (USCC) certifies compost products under its Seal of Testing Assurance (STA)
Program. Compost producers whose products have been certified through the ST A Program provide
customers with a standard product label that allows comparison between compost products. Only STA
certified, Class I compost should be used.
November 2010
Compost Blankets and Berms
. Functions:·, -' . . .. ..
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
-.. . ..
. ,,, . . "' ~ . ,
Yes
Moderate
No
CB-1
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EC-5 Compost Blanket and Filter Berm (CB)
Maintenance and Removal
When rills or gullies develop in an area that has been composted, fill and cover the area with additional
compost and install berms as necessary to help reduce erosion.
Weed control can be a maintenance challenge in areas using compost blankets. A weed control strategy
may be necessary, including measures such as mechanical removal and spot application of targeted
herbicides by licensed applicators.
For compost berms, accumulated sediments should be removed from behind the berm when the sediments
reach approximately one third the height of the berm. Areas that have been washed away should be
replaced. If the berm has experienced significant or repeated washouts, a compost berm may not be the
appropriate BMP for this area.
Compost blankets and berms biodegrade and do not typically require removal following site stabilization.
CB-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010 ~,
L·,ff:t -n ··ce--·m·-·xtt..,
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Compost Blanket and Filter Berm (CB) EC-5
MIN
CLASS 1 COMPOST FILTER BERM
1" TO 3" THICK (2" T'(P.) STA
CERTIFIED CLASS 1 COMPOST BLANKET
TABLE CB-1. CLASS 1 COMPOST
PARAMETERS CHARACTERISTIC
MINIMUM STABIUT'( INDICATOR STABLE TO VERY STABLE
SOLUBLE SALTS MAXIMUM 5 mm hos/ cm
PH 6.0 -8.0
AG INDEX > 10
MATURITY INDICATOR EXPRESSED AS 80+/80+
PERCENTAGE OF GERMINATION/VIGOR
MATURITY INDICATOR EXPRESSED AS < 4
AMMONIA N/ NITRATE N RATIO
MATURITY INDEX AS CARBON TO 20:1
NITROGEN RATIO
TESTED FOR CLOPYRALID YES/NEGATNE RESULT
MOISTURE CONTENT 30-60%
ORGANIC MATTER CONTENT 25-45% OF DRY WEIGHT
PARTICLE SIZE DISTRIBUTION 3" (75mm) 100% PASSING
PRIMARY, SECONDARY NUTRIENTS; TRACE MUST BE REPORTED
ELEMENTS
TESTING AND TEST REPORT SUBMITTAL STA + CLOPYRALID
REQUIREMENTS
ORGANIC MATTER PER CUBIC YARD MUST REPORT
CHEMICAL CONTAMINANTS COMPLY WITH US £PA CLASS A STANDARD, 40 CFR
503. 1 TABLES 1 & 3 LEVELS
MINIMUM MANUFACTURING/PRODUCTION FULLY PERMlfilD UNDER COLORADO DEPARTMENT OF
REQUIREMENT PUBLIC HEALTH AND ENVIRONMENT, HAZARDOUS
MATERIALS AND WASTE MANAGEMENT DIVISION
RISK FACTOR RELATING TO PLANT LOW
GERMINATION AND HEALTH
CB-1. COMPOST BLANKET AND COMPOST FILTER BERM
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
CB-3
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EC-5
CB-4
Compost Blanket and Filter Berm (CB)
COMPOS[ EILfER BERM AND COMPOST Bl ANKEf INSfAI I AUON NOfES
1. SEE PLAN VIEW FOR
-LOCATION OF COMPOST FILTER BERM(S).
-LENGTH OF COMPOST FILTER BERM(S).
2. COMPOST BERMS ANO BLANKETS MAY BE USED IN PLACE OF STRAW MULCH OR
GEOTEXTILE FABRIC IN AREAS WHERE ACCESS TO LANDSCAPING IS DIFFICULT DUE TO
LANDSCAPING OR OTHER OBJECTS OR IN AREAS WHERE A SMOOTH TURF GRASS FINISH IS
DESIRED.
J. FILTER BERMS SHALL RUN PARALLEL TO THE CONTOUR.
4. FILTER BERMS SHALL BE A MINIMUM OF 1 FEET HIGH AND 2 FEET WIDE.
5. FILTER BERMS SHALL BE APPLIED BY PNEUMATIC BLOWER OR BY HANO.
6. FILTER BERMS SHALL ONLY BE UTILIZED IN AREAS WHERE SHEET FLOW CONDITIONS
PREVAIL ANO NOT IN AREAS OF CONCENTRATED FLOW.
7. COMPOST BLANKETS SHALL BE APPLIED AT A DEPTH OF 1 -3 INCHES (TYPICALLY 2
INCHES). FOR AREAS WITH EXISTING VEGETATION THAT ARE TO BE SUPPLEMENTED BY
COMPOST, A THIN 0.5-INCH LAYER MAY BE USED.
8. SEEDING SHALL BE PERFORMED PRIOR TO THE APPLICATION OF COMPOST. ALTIERNATIVELY,
SEED MAY BE COMBINED WITH COMPOST ANO BLOWN WITH THE PNEUMATIC BLOWER.
9. WHEN TURF GRASS FINISH IS NOT DESIRED, SURFACE ROUGHENING ON SLOPES SHALL
TAKE PLACE PRIOR TO COMPOST APPLICATION.
10. COMPOST SHALL BE A CLASS I COMPOST AS DEFINED BY TABLE CB-1.
COMPOS[ flLfER BERM MAINfENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS ANO CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. COMPOST BERMS ANO BLANKETS SHALL BE REAPPLIED OR REGRADED AS NECESSARY IF
RILLING IN THE COMPOST SURFACE OCCURS.
(DETJ>JLS ADAPTED FROM AR>PAHOE COUNTY, COl.OAAOO, NOT AV.AIL.ASL£ IN AUTOC>D)
N.Q.IEl MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UOFCO STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Rolled Erosion Control Products (RECP) EC-6
Description
Rolled Erosion Control Products
(RECPs) include a variety of
temporary or permanently installed
manufactured products designed to
control erosion and enhance vegetation
establishment and survivability,
particularly on slopes and in channels.
For applications where natural
vegetation alone will provide sufficient
permanent erosion protection,
temporary products such as netting,
open weave textiles and a variety of
erosion control blankets (ECBs) made
of biodegradable natural materials
( e.g., straw, coconut fiber) can be used.
For applications where natural
Photograph RECP-1. Erosion control blanket protecting the slope from
erosion and providing favorable conditions for rcvegetation.
vegetation alone will not be sustainable under expected flow conditions, permanent rolled erosion control
products such as turf reinforcement mats (TRMs) can be used. In particular, turfreinforcement mats are
designed for discharges that exert velocities and sheer stresses that exceed the typical limits of mature
natural vegetation.
Appropriate Uses
RECPs can be used to control erosion in conjunction with revegetation efforts, providing seedbed
protection from wind and water erosion. These products are often used on disturbed areas on steep
slopes, in areas with highly erosive soils, or as part of drainageway stabilization. In order to select the
appropriate RECP for site conditions, it is important to have a general understanding of the general types
of these products, their expected longevity, and general characteristics.
The Erosion Control Technology Council (ECTC 2005) characterizes rolled erosion control products
according to these categories:
•
•
•
Mulch control netting: A planar woven natural fiber or extruded geosynthetic mesh used as a
temporary degradable rolled erosion control product to anchor loose fiber mulches.
Open weave textile: A temporary degradable rolled erosion control product composed of processed
natural or polymer yams woven into a matrix, used to provide erosion control and facilitate
vegetation establishment.
Erosion control blanket (ECB): A temporary
degradable rolled erosion control product composed of
processed natural or polymer fibers which are
mechanically, structurally or chemically bound together
to form a continuous matrix to provide erosion control
and facilitate vegetation establishment. ECBs can be
further differentiated into rapidly degrading single-net
and double-net types or slowly degrading types.
Rolled Erosion Control Products
.
Functions
Erosion Control Yes
Sediment Control No
Site/Material Management No
November 20 IO Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
RECP-1
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EC-6 Rolled Erosion Control Products (RECP)
• Turf Reinforcement Mat (TRM): A rolled erosion control product composed of non-degradable
synthetic fibers, filaments, nets, wire mesh, and/or other clements, processed into a permanent, three-
dimensional matrix of sufficient thickness. TRMs, which may be supplemented with degradable
components, are designed to impart immediate erosion protection, enhance vegetation establishment
and provide long-term functionality by permanently reinforcing vegetation during and after
maturation. Note: TRMs arc typically used in hydraulic applications, such as high flow ditches and
channels, steep slopes, stream banks, and shorelines, where erosive forces may exceed the limits of
natural, unreinforced vegetation or in areas where limited vegetation establishment is anticipated.
Tables RECP-1 and RECP-2 provide guidelines for selecting rolled erosion control products appropriate
to site conditions and desired longevity. Table RECP-1 is for conditions where natural vegetation alone
will provide permanent erosion control, whereas Table RECP-2 is for conditions where vegetation alone
will not be adequately stable to provide long-term erosion protection due to flow or other conditions.
RECP-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Rolled Erosion Control Products (RECP) EC-6
Table RECP-1. ECTC Standard Specification for Temporary Rolled Erosion Control Products
(Adapted from Erosion Control Technology Council 2005)
Slope Channel Minimum Expected
Product Description Tensile Longevity Applications* Applications* Strength'
Maximum C Factor2'5 Max. Shear
Gradient Stress3•
4
•6
Mulch Control Nets 5: 1 (H:V) <:0.10@ 0.25 lbs/ft 2 5 lbs/ft
5: I (12 Pa) (0.073 kN/m)
Netless Rolled <:0.10@ 0.5 lbs/ft2 5 lbs/ft Erosion Control 4:1 (H:V) 4:1 (24 Pa) (0.073 kN/m) Blankets Up to 12
Single-net Erosion months
Control Blankets & 3:1 (H:V) <:0.15@ 1.5 lbs/ft2 50 lbs/ft
Open Weave Textiles 3: I (72 Pa) (0.73 kN/m)
Double-net Erosion 2: I (H:V) <:0.20@ 1.75 lbs/ft2 75 lbs/ft
Control Blankets 2:1 (84 Pa) (1.09 kN/m)
Mulch Control Nets 5:1 (H:V) <:0.10@ 0.25 lbs/ft2 25 lbs/ft 24 months 5: I (12Pa) (0.36 kN/m)
Erosion Control
Blankets & Open 1.5: I (H:V) <:0.25@ 2.00 lbs/ft2 I 00 lbs/ft 24 months Weave Textiles 1.5: I (96 Pa) (1.45 kN/m)
( slowly degrading)
Erosion Control <:0.25@ 2.25 lbs/ft2 125 lbs/ft Blankets & Open 1:1 (H:V) 36 months
Weave Textiles I: 1 (108 Pa) (1.82 kN/m)
* C Factor and shear stress for mulch control nettings must be obtained with netting used in conjunction
with pre-applied mulch material. (See Section 5.3 of Chapter 7 Constrnction BMPsfor more information
on the CF actor.)
1 Minimum Average Roll Values, Machine direction using ECTC Mod. ASTM D 5035.
2 C Factor calculated as ratio of soil loss from RECP protected slope (tested at specified or greater
gradient, H:V) to ratio of soil loss from unprotected (control) plot in large-scale testing.
3 Required minimum shear stress RECP ( unvegetated) can sustain without physical damage or excess
erosion(> 12.7 mm (0.5 in) soil loss) during a 30-minute flow event in large-scale testing.
4 The permissible shear stress levels established for each performance category are based on historical
experience with products characterized by Manning's roughness coefficients in the range of0.01 -0.05.
5 Acceptable large-scale test methods may include ASTM D 6459, or other independent testing deemed
acceptable by the engineer.
6 Per the engineer's discretion. Recommended acceptable large-scale testing protocol may include ASTM
D 6460, or other independent testing deemed acceptable by the engineer.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
RECP-3
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EC-6 Rolled Erosion Control Products (RECP)
Table RECP-2. ECTC Standard Specification for Permanent' Rolled Erosion Control Products
(Adapted from: Erosion Control Technology Council 2005)
Product Type Slope Channel Applications Applications
Maximum Maximum Minimum
Gradient Shear Strcss4•5 Tensile
Strength 2•3
TRMs with a minimum thickness of 0.5: I (H:V) 6.0 lbs/ft 2 (288 Pa) 125 lbs/ft (1.82
0.25 inches (6.35 mm) per ASTM D kN/m)
6525 and UV stability of 80% per
ASTM D 4355 (500 hours 0.5: 1 (H:V) 8.0 lbs/ft 2 (384 Pa) 150 lbs/ft (2.19
exposure). kN/m)
0.5: 1 (H:V) 10.0 lbs/ft 2 (480 Pa) 175 lbs/ft (2.55
kN/m)
1 For TRMs containing degradable components, all property values must be obtained on the non-
degradable portion of the matting alone.
2 Minimum Average Roll Values, machine direction only for tensile strength determination-using ASTM
D 6818 (Supersedes Mod. ASTM D 5035 for RECPs)
3 Field conditions with high loading and/or high survivability requirements may warrant the use of a TRM
with a tensile strength of 44 kN/m (3,000 lb/ft) or greater.
4 Required minimum shear stress TRM (fully vegetated) can sustain without physical damage or excess
erosion(> 12.7 mm (0.5 in.) soil loss) during a 30-minute flow event in large scale testing.
5 Acceptable large-scale testing protocols may include ASTM D 6460, or other independent testing
deemed acceptable by the engineer.
Design and Installation
RECPs should be installed according to manufacturer's specifications and guidelines. Regardless of the
type of product used, it is important to ensure no gaps or voids exist under the material and that all
comers of the material are secured using stakes and trenching. Continuous contact between the product
and the soil is necessary to avoid failure. Never use metal stakes to secure temporary erosion control
products. Often wooden stakes are used to anchor RECPs; however, wood stakes may present installation
and maintenance challenges and generally take a long time to biodegrade. Some local jurisdictions have
had favorable experiences using biodegradable stakes.
This BMP Fact Sheet provides design details for several commonly used ECB applications, including:
ECB-1 Pipe Outlet to Drainagcway
ECB-2 Small Ditch or Drainagcway
ECB-3 Outside of Drainageway
RECP-4 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Rolled Erosion Control Products (RECP) EC-6
Staking patterns arc also provided in the design details according to these factors:
• ECB type
• Slope or channel type
For other types of RECPs including TRMs, these design details are intended to serve as general
guidelines for design and installation; however, engineers should adhere to manufacturer's installation
recommendations.
Maintenance and Removal
Inspection of erosion control blankets and other RECPs includes:
• Check for general signs of erosion, including voids beneath the mat. If voids are apparent, fill the
void with suitable soil and replace the erosion control blanket, following the appropriate staking
pattern.
• Check for damaged or loose stakes and secure loose portions of the blanket.
Erosion control blankets and other RECPs that are biodegradable typically do not need to be removed
after construction. If they must be removed, then an alternate soil stabilization method should be installed
promptly following removal.
Turf reinforcement mats, although generally resistanito biodegradation, are typically left in place as a
dense vegetated cover grows in through the mat matrix. The turf reinforcement mat provides long-term
stability and helps the established vegetation resist erosive forces.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
RECP-5
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EC-6 Rolled Erosion Control Products (RECP)
UNDISTURBED
SOIL~ I
PERIMETER
ANCHOR
TRENCH. TYP.
TYPE OF ECB AS INDICATED IN PLAN VIEW. INSTALL IN ALL
DISTURBED AREAS OF STREAMS AND DRNNAGE CHANNELS TD DEPTH
COMPACTED
BACKFILL, TYP.
PERIMETER ANCHOR TRENCH
D ABOVE CHANNEL INVERT. ECB SHALL GENERALLY BE ORIENTED >-------------<
PARALLEL TD FLOW DIRECTION (I.E. LONG DIMENSIONS OF BLANKET
PARALLEL TD FLOWUNES) STAKING PATTERN SHALL MATCH ECB
ANO/OR CHANNEL TYPE.
ECB-1. PIPE OUTLET TO DRAINAGEWAY
JOINT ANCHOR
TRENCH, TYP.
TYPE OF ECB,
INDICATED IN PLAN VIEW
ECB SHALL
EXTEND TO THE
TDP OF THE
CHANNEL
\
PERIMETER ANCHOR
TRENCH, TYP.
COMPACTED
SUBGRADE
STAKING PATTERN PER MANUFACTURER SPEC. OR PATTERN
BASED ON ECB AND/OR CHANNEL TYPE (SEE STAKING
PATTERN DETAIL)
ECB-2. SMALL DITCH OR DRAINAGEWAY
TWO EDGES
OF TWO
ADJACENT
ROLLS
JOINT ANCHOR TRENCH
LOOP FROM
MIDDLE OF
ROLL
INTERMEDIATE ANCHOR TRENCH
FLOW ---1 ~ 1--6"
OVERLAPPING JOINT
---j I-3" MIN.
12" Jr7
MIN. lV
WOOD STAKE DETAIL
RECP-6 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Rolled Erosion Control Products (RECP)
DIVERSION DITCH
TYPICALLY AT TOP OF
SLOPE
STAGGER OVERLAPS
OVERLAPPING JOINT
EC-6
y ,, TAKING PATTERN PER
" ' ' MANUFACTURER SPEC. OR PATTERN
BASED ON £CB AND/OR SLOPE
TYPE (SEE STAKING PATTERN DETAIL)
PERIMETER
ANCHOR
TRENCH OR
JOINT, TYP.
ECB-3. OUTSIDE OF DRAINAGEWAY
ROLL I WIDTH I
W, TYP.
w
3'
I O I ½ w
0 0 lo e·I ~½ ½W -1 ½W
0 I3• 4•I _l_ -j ½ w 0 0
T 0 0
0 T2·
STRAW STRAW-COCONUT COCONUT OR EXCELSIOR
STAKING PATTERNS BY ECB TYPE
'{fr·· 6'
4 ·~1 o _:_b ,-Y. w 11-b -½w
0 0
4:1-3:1
SLOPES ~ 3:1-2:1
SLOPES
2: 1 AND STEEPER
SLOPES
I -I ½W
4' 11
20"
0 0 0
f-
4' 0 0 0
20" ~o· L 2·
0 0 0
LOW FLOW CHANNEL HIGH FLOW CHANNEL
STAKING PATTERNS BY SLOPE OR CHANNEL TYPE
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
RECP-7
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EC-6
RECP-8
Rolled Erosion Control Products (RECP)
EROSION CONTROL BLANKET INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATION OF ECB.
-TYPE OF £CB (STRAW, STRAW-COCONUT, COCONUT, OR EXCELSIOR).
-AREA, A, IN SQUARE YARDS OF EACH TYPE OF ECB
2. 100% NATURAL AND BIODEGRADABLE MATERIALS ARE PREFERRED FOR RECPs, ALTHOUGH
SOME JURISDICTIONS MAY ALLOW OTHER MATERIALS IN SOME APPLICATIONS.
3. IN AREAS WHERE ECBs ARE SHOWN ON THE PLANS, THE PERMITTEE SHALL PLACE
TOPSOIL ANO PERFORM FINAL GRADING, SURFACE PREPARATION, ANO SEEDING ANO MULCHING.
SUBGRADE SHALL BE SMOOTH AND MOIST PRIOR TO ECB INSTALLATION ANO THE ECB SHALL
BE IN FULL CONTACT WITH SUBGRADE. NO GAPS OR VOIDS SHALL EXIST UNDER THE
BLANKET.
4. PERIMETER ANCHOR TRENCH SHALL BE USED ALONG THE OUTSIDE PERIMETER OF ALL
BLANKET AREAS.
5. JOINT ANCHOR TRENCH SHALL BE USED TO JOIN ROLLS OF ECBs TOGETHER
(LONGITUDINALLY AND TRANSVERSELY) FOR ALL ECBs EXCEPT STRAW WHICH MAY USE
AN OVERLAPPING JOINT.
6. INTERMEDIATE ANCHOR TRENCH SHALL BE USED AT SPACING OF ONE-HALF ROLL LIENGTH
FOR COCONUT AND EXCELSIOR ECBs.
7. OVERLAPPING JOINT DETAIL SHALL BE USED TO JOIN ROLLS OF ECBs TOGETHER FOR EC8s
ON SLOPES.
8. MATERIAL SPECIFICATIONS OF ECBs SHALL CONFORM TO TABLIE ECB-1.
9. ANY AREAS OF SEEDING ANO MULCHING DISTURBED IN THE PROCESS OF INSTALLING ECBS
SHALL BE RESEEDED AND MULCHED.
10. DETAILS ON DESIGN PLANS FOR MAJOR ORAINAGEWAY STABILIZATION WILL GOVERN IF
DIFFERENT FROM THOSE SHOWN HERE.
TABLE ECB-1. ECB MATERIAL SPECIFICATIONS
TYPE COCONUT STRAW EXCELSIOR RECOMMENDED
CONTENT CONTENT CONTENT NETTINGU
STRAW• -100% -DOUBLE/
NATURAL
STRAW-30% MIN 70% MAX DOUBLE/
COCONUT -NATURAL
COCONUT 100% --DOUBLE/
NATURAL
EXCELSIOR 100% DOUBLE/ --NATURAL
"STRAW ECBs MAY ONLY BE U::.ai UTSlur. ur ;:, I !"IC MS AND o~rNAG '--~NEL
••ALTERNATE NETTING MAY 8E ACCEPTABl£ IN SOME JURISDICTIONS
Urban Drainage and Flood Control District
Urban Stonn Drainage Criteria Manual Volume 3
November 2010
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Rolled Erosion Control Products (RECP) EC-6
EROSION CONTRQI 61 AN KET MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR DR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. ECBs SHALL BE LEFT IN PLACE TO EVENTUALLY BIODEGRADE, UNLESS REQUESTED TO BE
REMOVED BY THE LOCAL JURISDICTION.
5. ANY ECB PULLED OUT, TORN, OR OTHERWISE DAMAGED SHALL BE REPAIRED OR
REINSTALLED. ANY SUBGRADE AREAS BELOW THE GEOTEXTILE THAT HAVE ERODED TO CREATED
A VOID UNDER THE BLANKET, OR THAT REMAIN DEVOID OF GRASS SHALL BE REPAIRED,
RESEEDED AND MULCHED AND THE ECB REINSTALLED.
1!.QJL MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY f'ROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
(DET.IJLS ~N'TEO fROM DOUGLAS COUNTY, COLORADO AND TOWN OF PARKER COLORADO, NOT AVAILABLE lN >.UTOCAD)
November 20 I 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
RECP-9
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Temporary Slope Drains (TSO) EC-7
Description
A temporary slope drain is a pipe or culvert used to convey water down a slope where there is a high
potential for erosion. A drainage channel or swale at the top of the slope typically directs upgradicnt
runoff to the pipe entrance for conveyance down the slope. The pipe outlet must be equipped with outlet
protection.
Photograph TSD-1. A temporary slope drain installed to convey runoff down a slope during construction. Photo
courtesy of the City of Aurora.
Appropriate Uses
Use on long, steep slopes when there is a high potential of flow concentration or rill development.
Design and Installation
Effective use of temporary slope drains involves design of an effective collection system to direct flows to
the pipe, proper sizing and anchoring of the pipe, and outlet protection. Upgradient of the temporary
slope drain, a temporary drainage ditch or swale should be constructed to collect surface runoff from the
drainage area and convey it to the drain entrance. The temporary slope drain must be sized to safely
convey the desired flow volume. At a minimum, it should be sized to convey the 2-year, 24-hour storm.
Temporary slope drains may be constructed of flexible or rigid pipe, riprap, or heavy (30 mil) plastic
lining. When piping is used, it must be properly anchored by burying it with adequate cover or by using
an anchor system to secure it to the ground.
The discharge from the slope drain must be directed to a stabilized outlet, temporary or permanent
channel, and/or sedimentation basin.
Sec Detail TSO-I for additional sizing and design
information. Temporary Slope Drains
..
Functions .
Erosion Control
Sediment Control
Site/Material Manai,ement
November 20 I 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Yes
No
No
SD-I
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EC-7 Temporary Slope Drains (TSD)
Maintenance and Removal
Inspect the entrance for sediment accumulation and remove, as needed. Clogging as a result of sediment
deposition at the entrance can lead to ponding upstream causing flooding or overtopping of the slope
drain. Inspect the downstream outlet for signs of erosion and stabilize, as needed. It may also be
necessary to remove accumulated sediment at the outfall. Inspect pipe anchors to ensure that they are
secure. If the pipe is secured by ground cover, ensure erosion has not compromised the depth of cover.
Slope drains should be removed when no longer needed or just prior to installation of permanent slope
stabilization measures that cannot be installed with the slope drain in place. When slope drains are
removed, the disturbed areas should be covered with topsoil, seeded, mulched or otherwise stabilized as
required by the local jurisdiction.
SD-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Temporary Slope Drains (TSD) EC-7
0
PIPE MUST BE ANCHORED
COMPACTED
EMBANKMENT
BERM
12" MIN (TOP §)s 0 OF PIPE TO TOP
OF EMBANKMENT, I CHECK HEADWATER
.--DEPTH) WITH SOIL OR OTHER -----------• ~3 _
SUITABLE ANCHOR ~
½ ,, -,,,...,
1// .,.;,,;;
RIPRAP
RIPRAP
BEDDING 6xD50
MIN
2xD50 MIN
T
SCH 40 PIPE D= 12" (MIN)
PLASTIC PIPE, HEAVY CANVAS
STOCK, RIPRAP LINED TRENCH,
OR GEOMEMBRANE LINED TRENCH
TEMPORARY SLOPE DRAIN PROFILE
COMPACTED
EMBANKMENT BERM
4xD
MIN RIPRAP
12" MIN COVER (CHECK HEADWATER DEPTH
AND PROVlDE FOR ARMORED OVERFLOW
FOR EVENTS EXCEEDING DESIGN STORM)
SECTION A
COMPACTED
EMBANKMENT
BERM
PERIMETER ANCHOR
TRENCH, SEE ECB
TERMINATION OF RIPRAP
LINED SLOPE DRAIN
GEOMEMBRANE
LINED SLOPE DRAIN
PERIMETER ANCHOR
TRENCH, SEE ECB D (10" MIN)
1L::.:::::::7:::=::n---
?3 I 4xD I
MIN
30 MIL (MIN) IMPERMEABLE
GEOMEMBRANE
TERMINATION OF GEOMEMBRANE LINED SLOPE DRAIN
November 2010
TSD-1. TEMPORARY SLOPE DRAIN PROFILE
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SD-3
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EC-7
SD-4
Temporary Slope Drains (TSO)
SLOPE DRAIN INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATION AND LENGTH OF SLOPE DRAIN
-PIPE DIAMETER, D, AND RIPRAP SIZE, 050.
2. SLOPE DRAIN SHALL BE DESIGNED TO CONVEY PEAK RUNOFF FOR 2-YEAR 24-HOUR
STORM AT A MINIMUM. FOR LONGER DURATION PROJECTS, LARGER MAY BE APPROPRIATE.
3. SLOPE DRAIN DIMENSIONS SHALL BE CONSIDERED MINIMUM DIMENSIONS; CONTRACTOR MAY
ELECT TO INSTALL LARGER FACILITIES.
4. SLOPE DRAINS INDICATED SHALL BE INSTALLED PRIOR TO UPGRADIENT LAND-DISTURBING
ACTIVITIES.
5. CHECK HEADWATER DEPTHS FOR TEMPORARY AND PERMANENT SLOPE DRAINS. DETAILS
SHOW MINIMUM COVER; INCREASE AS NECESSARY FOR DESIGN HEADWATER DEPTH.
6. RIPRAP PAD SHALL BE PLACED AT SLOPE DRAIN OUTFALL.
7. ANCHOR PIPE BY COVERING WITH SOIL OR AN ALTERNATE SUITABLE ANCHOR MATERIAL.
$LOPE PBAIN MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, ANO MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOUUD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs PS SOON PS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE ME/>SURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. INSPECT INLET AND OUTILET POINTS AIFTER STORMS FOR CLOGGING OR EVIDENCE OF
OVERTOPPING. BREACHES IN PIPE OR OTHER CONVEYANCE SHALL BE REPAIRED AS SOON AS
PRACTICABLE IF OBSERVED.
5. INSPECT RIPRAP PAD AT OUTLET FOR SIGNS OF EROSION. IF SIGNS OF EROSION EXIST,
ADDITIONAL ARMORING SHALL BE INSTALLED.
6. TEMPORARY SLOPE DRAINS ARE TO REMAIN IN PLACE UNTIL NO LONGER NEEDED, BUT
SHALL BE REMOVED PRIOR TO THE ENO OF CONSTRUCTION. WHEN SLOPE DRAINS ARE
REMOVED, THE DISTURBED AREA SHALL BE COVERED WITH TOP SOIL, SEEDED, MULCHED OR
OTHERWISE STABILIZED IN A MANNER APPROVED BY THE LOCAL JURISDICTION.
(DETAIL ADAPTED FROM DOUGLAS COUNTY, COLORl\00 ANO TiiE C1TY Of COLORIIOO SPRINCS, COLORADO, NOT AVAILJIBL.E IN
AUTOCAD)
llilIE.;. MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS PS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Temporary Outlet Protection {TOP)
Description
Outlet protection helps to reduce erosion
immediately downstream of a pipe,
culvert, slope drain, rundown or other
conveyance with concentrated, high-
velocity flows. Typical outlet protection
consists of riprap or rock aprons at the
conveyance outlet.
Appropriate Uses
Outlet protection should be used when a
conveyance discharges onto a disturbed
area where there is potential for accelerated
erosion due to concentrated flow. Outlet
Photograph TOP-1. Riprap outlet protection.
EC-8
protection should be provided where the velocity at the culvert outlet exceeds the maximum permissible
velocity of the material in the receiving channel.
Note: This Fact Sheet and detail are for temporary outlet protection, outlets that are intended to be used
for less than 2 years. For permanent, long-term outlet protection, see the Major Drainage chapter of
Volume I.
Design and Installation
Design outlet protection to handle runoff from the largest drainage area that may be contributing runoff
during construction (the drainage area may change as a result of grading). Key in rock, around the entire
perimeter of the apron, to a minimum depth of 6 inches for stability. Extend riprap to the height of the
culvert or the normal flow depth of the downstream channel, whichever is less. Additional erosion
control measures such as vegetative lining, turf reinforcement mat and/or other channel lining methods
may be required downstream of the outlet protection if the channel is susceptible to erosion. See Design
Detail OP-I for additional information.
Maintenance and Removal
Inspect apron for damage and displaced rocks. If rocks are missing or significantly displaced, repair or
replace as necessary. !frocks are continuously missing or displaced, consider increasing the size of the
riprap or deeper keying of the perimeter.
Remove sediment accumulated at the outlet before the outlet protection becomes buried and ineffective.
When sediment accumulation is noted, check that upgradient BMPs, including inlet protection, are in
effective operating condition.
Outlet Protection
I· ~· :·•----''-· -._, --;+•s' ">"'/:'
I/unctions ..
Erosion Control
Sediment Control
Outlet protection may be removed once the pipe is no longer
draining an upstream area, or once the downstream area has
been sufficiently stabilized. If the drainage pipe is
permanent, outlet protection can be left in place; however,
permanent outlet protection should be designed and
constructed in accordance with the requirements of the
Major Drainage chapter of Volume 2.
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Stonn Drainage Criteria Manual Volume 3
·: . "'.: ,,
Yes
Moderate
No
TOP-!
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EC-8
TOP-2
Temporary Outlet Protection (TOP)
J(Do)
EXTEND RIPRAP TO HEIGHT OF
\
CULVERT OR. NORMAL CHANNEL
TH, WHICHEVER IS LESS
~
~. "'
4(Do)
TEMPORARY OUTLET PROTECTION PLAN
NON-WOVEN
GEOTEXTILE
SECTION A
KEY IN TO 2 x D50
AROUND PERIMETER
TABLE OP-1. TEMPORARY OUTLET PROTECTION
SIZING TABLE
PIPE APRON RIPRAP D50
DIAMETER, DISCHARGE, LENGTH, Lo DIAMETER
Do Q (CFS) (FT) MIN
(INCHES) (INCHES)
8 2.5 5 4
5 10 6
12 5 10 4
10 13 6
10 10 6
18 20 16 9
JO 23 12
40 26 16
30 16 g
24 40 26 g
50 26 12
60 30 16
OP-1. TEMPORARY OUTLET PROTECTION
Urban Drainage and Flood Control District
Urban Stonn Drainage Criteria Manual Volume 3
November 2010
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Temporary Outlet Protection (TOP) EC-8
TEMPORARY O\ ITI ET PROTECTION INSTALLATION NOTES
1. SEE PLAN VIEW FOR
-LOCATION OF OUTLET PROTECTION.
-DIMENSIONS OF OUTLET PROTECTION.
2. DETAIL IS INTENDED FOR PIPES WITH SLOPE ~ I 0%. ADDITIONA/L EVALUATION OF RIPRAP
SIZING AND OUTLET PROTECTION DIMENSIONS REQUIRED FOR STEEPER SLOPES.
3. TEMPORARY OUTLET PROTECTION INFORMATION IS FOR OUTLETS INTENDED TO BE UTILIZED
LESS THAN 2 YEARS.
TEMPORARY OUTLET PROTECTION INSPECTION AND MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
NQIE;. MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS />S TO WHICH DETAIL SHOULID BE USED WHEN
DIFFERENCES ARE NOTED.
(DETAILS .IDAPTEO FROM M.JRORA, COLORADO ANO PREVIOUS VERSION OF VOLUME 3, NOT A.YAILAB..E IN AIJTOCAO)
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
TOP-3
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Rough Cut Street Control (RCS)
Description
Rough cut street controls arc rock or
earthen berms placed along dirt roadways
that are under construction or used for
construction access. These temporary
berms intercept sheet flow and divert
runoff from the roadway, and control
erosion by minimizing concentration of
flow and reducing runoff velocity.
Appropriate Uses
Appropriate uses include:
• Temporary dirt construction roadways
that have not received roadbase. Photograph RCS-I. Rough cut street controls.
EC-9
• Roadways under construction that will not be paved within 14 days of final grading, and that have not
yet received roadbase.
Design and Installation
Rough cut street controls are designed to redirect sheet flow off the dirt roadway to prevent water from
concentrating and eroding the soil. These controls consist of runoff barriers that are constructed at
intervals along the road. These barriers are installed perpendicular to the longitudinal slope from the
outer edge of the roadside swale to the crown of the road. The barriers are positioned alternately from the
right and left side of the road to allow construction traffic to pass in the lane not barred. If construction
traffic is expected to be congested and a vehicle tracking control has been constructed, rough-cut street
controls may be omitted for 400 feet from the entrance. Runoff from the controls should be directed to
another stormwater BMP such as a roadside swale with check dams once removed from the roadway. See
Detail RCS-I for additional information.
Maintenance and Removal
Inspect street controls for erosion and stability. If rills are forming in the roadway or cutting through the
control berms, place the street controls at shorter intervals. If earthen berms are used, periodic
recompaction may be necessary. When rock berms arc used,
repair and/or replace as necessary when damaged. Street
controls may be removed 14 days prior to road surfacing and
Rough Cut Street Control
pavmg.
November 20 I 0
Functions .
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Yes
Moderate
No
RCS-I
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EC-9 Rough Cut Street Control (RCS)
SPACING
200' MAXIMUM
(SEE TABLE RCS-2)
PL-----.--,---1--------i----,=---i-
EXCAVATED
ROADBED
CL---+-
STREET __
SLOPE
X
W = 1 /2 ROADBED
WIDTH
SEE TABLE RCS-1 8' MINIMUM SPACING
FOR VEHICLE PASSAGE
PL.--_,_---1=---'P"c__ _________ L___
GEOTEXTILE SOCK(S} FlLLED WITH
RCS-2
CRUSHED ROCK OR COMPACTED
EARTHEN BERM(S)
ROUGH CUT STREET CONTROL PLAN
l
EXCAVATED ROADBED
SECTION A
w
FLOW_
GEOTEXTILE SOCK(S) FILLED
WITH CRUSH ROCK OR
COMPACTED EARTHEN BERM(S)
.:12" TO 18" ~ 112" TO 18"
SECTION B
TABLE RCS-I TABLE RCS-2
W (FT} X (FT) LONGITUDINAL SPACING (FT) STREET SLOPE(%)
20-30 5 <2 NOT TYPICALLY NEEDED
31-40 7
2 ' 200
3 200
41-50 9 4 150
51-60 10.5 5 100
6 50
61-70 12 7 25
8 25
RCS-1 . ROUGH CUT STREET CONTROL
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Rough Cut Street Control (RCS) EC-9
ROUGH cur STREET CONTROi INSTAI I ATION NOTES
1. SEE PLAN VIEW FOR
-LOCATION OF ROUGH CUT STREET CONTROL MEASURES.
2. ROUGH CUT STREET CONTROL SHALL BE INSTALLED AFTER A ROAD HAS BEEN cur IN.
ANO WILL NOT BE PAVED FOR MORE THAN 14 DAYS OR FOR TEMPORARY CONSTRUCTION
ROADS THAT HAVE NOT RECEIVED ROAD BASE.
ROUGH cur STREET CONTROL INSPECTION AND MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS ANO MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS ANO CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
(DETAILS ADAPTED FROM AURORA. COLORADO. NOT AVAILABt£ IN AUTOCAD)
IB,lE; MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAJL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
RCS-3
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Earth Dikes and Drainage Swales (ED/DS)
Description
Earth dikes and drainage swales are
temporary storm conveyance channels
constructed either to divert runoff around
slopes or to convey runoff to additional
sediment control BMPs prior to discharge
of runoff from a site. Drainage swales
may be lined or unlined, but if an unlined
swale is used, it must be well compacted
and capable ofresisting erosive velocities.
Appropriate Uses
EC-10
Earth dikes and drainage swales are
typically used to control the flow path of
runoff at a construction site by diverting
runoff around areas prone to erosion, such
as steep slopes. Earth dikes and drainage
swales may also be constructed as
temporary conveyance features. This will
direct runoff to additional sediment control
treatment BMPs, such as sediment traps or
basins.
Photograph ED/DS-1. Example ofan earth dike used to divert
flows at a construction site. Photo courtesy ofCDOT.
Design and Installation
When earth dikes are used to divert water for slope protection, the earth dike typically consists of a
horizontal ridge of soil placed perpendicular to the slope and angled slightly to provide drainage along the
contour. The dike is used in conjunction with a swale or a small channel upslope of the berm to convey
the diverted water. Temporary diversion dikes can be constructed by excavation of a V-shaped trench or
ditch and placement of the fill on the downslope side of the cut. There are two types of placement for
temporary slope diversion dikes:
■ A dike located at the top of a slope to divert upland runoff away from the disturbed area and convey it
in a temporary or permanent channel.
■ A diversion dike located at the base or mid-slope of a disturbed area to intercept runoff and reduce the
effective slope length.
Depending on the project, either an earth dike or drainage swale may be more appropriate. If there is a
need for cut on the project, then an excavated drainage
swale may be better suited. When the project is primarily·
fill, then a conveyance constructed using a berm may be the
Earth Dikes and Drainage Swales
better option.
All dikes or swales receiving runoff from a disturbed
area should direct stormwater to a sediment control
BMP such as a sediment trap or basin.
Functions
Erosion Control
Sediment Control
Site/Material Management
November 20 I 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Yes
Moderate
No
ED/DS-1
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EC-10 Earth Dikes and Drainage Swales (ED/DS)
Unlined dikes or swalcs should only be used for intercepting sheet flow runoff and arc not intended
for diversion of concentrated flows.
Details with notes arc provided for several design variations, including:
ED-I. Unlined Earth Dike formed by Berm
DS-1. Unlined Excavated Swale
DS-2. Unlined Swale Formed by Cut and Fill
DS-3. ECB-lincd Swale
DS-4. Synthetic-lined Swale
DS-5. Riprap-lined Swale
The details also include guidance on permissible velocities for cohesive channels ifunlined approaches
will be used.
Maintenance and Removal
Inspect earth dikes for stability, compaction, and signs of erosion and repair. Inspect side slopes for
erosion and damage to erosion control fabric. Stabilize slopes and repair fabric as necessary. If there is
reoccurring extensive damage, consider installing rock check dams or lining the channel with riprap.
If drainage swales are not permanent, remove dikes and fill channels when the upstream area is stabilized.
Stabilize the fill or disturbed area immediately following removal by revegetation or other permanent
stabilization method approved by the local jurisdiction.
ED/DS-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Earth Dikes and Drainage Swales (ED/DS) EC-10
(ED/\
~
TRANSVERSE
'---FLOW TO SWALE
"---EXISTING GRADE
ED-1. COMPACTED UNLINED EARTH DIKE FORMED BY BERM
SWALE
DS-2. COMPACTED UNLINED SWALE FORMED BY CUT AND
FILL
GEOTEXTILE OR MAT
(SEE ECB)
INTERMEDIATE ANCHOR TRENCH AT
ONE-HALF ROLL LENGTH
(SEE ECB)
W (5' MIN.) STAKES (SEE ECB)
DS-3. ECB LINED SWALE (CUT AND FILL OR BERM)
November 20 I 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
ED/DS-3
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EC-10 Earth Dikes and Drainage Swales (ED/DS)
JO MIL MIN.
THICKNESS
W 5' MIN.
!D (10" MIN.)
~----'----
NO
STAKING
ANCHOR TRENCH AT PERIMETER
OF BLANKET AND AT
':ff----OVERLAPPING JOINTS WITH ANY
INTERMEDIATE ANCHOR _/
TRENCH AT ONE-HALF ROLL
LENGTH SIMILAR TO ECB,
ADJACENT ROLLS OF BLANKET,
SIMILAR TO ECB, BUT NO
STAKING
TRANSVERSE ANCHOR TRENCHES AT PERIMETER OF
BLANKET AND AT OVERLAPPING JOINTS WITH ANY
ADJACENT ROLLS OF BLANKET, SIMILAR TO ECB, BUT
NO STAKING
BUT NO STAKING
DS-4. SYNTHETIC LINED SWALE
THICKNESS=2 X D50 W (5' MIN.)
LINE WITH AASHTO
#3 ROCK (CDOT SECT.
703, #J) OR RIPRAP
CALLED FOR IN THE
PLANS
DS-5. RIPRAP LINED SWALE
EARTH PIKE AND DRAINAGE SWA! E INSTAI I ATION NOTES
ED/DS-4
1. SEE SITE PLAN FOR:
-LOCATION OF DIVERSION SWALE
-TYPE OF SWALE {UNLINED, COMPACTED AND/OR LINED).
-LENGTH OF EACH SWALE.
-DEPTH, 0, ANO WIDTH, W DIMENSIONS.
-FOR ECB/TRM LINED DITCH, SEE ECB DETAIL.
-FOR RIPRAP LINED DITCH, SIZE OF RIPRAP, D50.
2. SEE DRAINAGE PLANS FOR DETAILS OF PERMANENT CONVEYANCE FACILITIES AND/OR
DIVERSION SWALES EXCEEDING 2-YEAR FLOW RATE OR JO CFS.
J. EARTH DIKES AND SWALES INDICATED ON SWMP PLAN SHALL BE INSTALLED PRIOR TO
LAND-DISTURBING ACTMTIES IN PROXIMITY.
4. EMBANKMENT IS TO BE COMPACTED TO 90% OF MAXIMUM DENSITY ANO WITHIN 2% OF
OPTIMUM MOISTURE CONTENT ACCORDING TO ASTM 0698.
5. SWALES ARE TO DRAIN TO A SEDIMENT CONTROL BMP.
6. FOR LINED DITCHES, INSTALLATION OF ECB/TRM SHALL CONFORM TO THE REQUIREMENTS
OF THE ECB DETAIL.
7. WHEN CONSTRUCTION TRAFFIC MUST CROSS A DIVERSION SWALE, INSTALL A TEMPORARY
CULVERT WITH A MINIMUM DIAMETER OF 12 INCHES.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Earth Dikes and Drainage Swales (ED/DS) EC-10
EARTH PIKE AND DRAINAGE $WAI E MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAJNTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAJLURE.
4. SWALES SHALL REMAJN IN PLACE UNTIL THE END OF CONSTRUCTION; IF AJPPROVED BY
LOCAJL JURISDICTION, SWALES MAY BE LEFT IN PLACE.
5. WHEN A SWALE IS REMOVED, THE DISTURBED AREA SHALL BE COVERED WITH TOPSOIL,
SEEDED AND MULCHED OR OTHERWISE STAJBILIZED IN A MANNER APPROVED BY LOCAL
JURISDICTION.
(DETAIL ADAPTED FROM DOUGLAS COUNTY, COLORADO ANO THE CITY or COLORADO SPRlNCS, COLORADO. NOT AVAILABLE IN
AUTOCAO)
NQIB MANY JURISDICTIONS HAVE BMP DETAJLS THAT VARY FROM UDFCD STANDARD DETAJLS.
CONSULT WITH LOCAJL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
November 20 IO Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
ED/DS-5
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Terracing (TER)
. Description
Terracing involves grading steep slopes
into a series of relatively flat sections, or
terraces, separated at intervals by steep
slope segments. Terraces shorten the
uninterrupted flow lengths on steep
slopes, helping to reduce the
development of rills and gullies.
Retaining walls, gabions, cribbing,
deadman anchors, rock-filled slope
mattresses, and other types of soil
retention systems can be used in
terracing.
Appropriate Uses
EC-11
Photograph TER-1. Use of a terrace to reduce erosion by controlling
slope length on a long, steep slope. Photo courtesy of Douglas
Countv.
Terracing techniques are most typically used to control erosion on slopes that are steeper than 4: I.
Design and Installation
Design details with notes are provided in Detail TER-1.
The type, number, and spacing of terraces will depend on the slope, slope length, and other factors. The
Revised Universal Soil Loss Equation (RUSLE) may be helpful in determining spacing of terraces on
slopes. Terracing should be used in combination with other stabilization measures that provide cover for
exposed soils such as mulching, seeding, surface roughening, or other measures.
Maintenance and Removal
Repair rill erosion on slopes and remove accumulated sediment, as needed. Terracing may be temporary
or permanent. If terracing is temporary, the slope should be topsoiled, seeded, and mulched when the
slope is graded to its final configuration and terraces arc removed. Due to the steepness of the slope, once
terraces are graded, erosion control blankets or other stabilization measures are typically required. If
terraces are permanent, vegetation should be established on slopes and terraces as soon as practical.
November 2010
Terracing .
Functions
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Yes
Moderate
No
TER-1
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EC-11 Terracing (TER)
TER-2
,--,
L_ __ _J
w
(8' MIN.) . H . EXISTING --+ --+-_ r GRADE
"H" VARIES ----. --/
(15' MAX.) -..._ .....__
SEE GRADING PLAN .....__ .....__
FINISHED
GRADE
.....__ .....__ .....__
19 .__:::::::=::::;;..,~3%~, MIN .. TYP.
TER-1. TERRACING
TERRACING INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATION OF TERRACING
-WIDTH (W), AND SLOPE (Z).
2. TERRACING IS TYPICALLY NOT REQUIRED FOR SLOPES OF 4:1 OR FLATTER.
3. GRADE TERRACES TO DRAIN BACK TO SLOPE AT A MINIMUM OF 3% GRADE.
TERRACING MAINTENANCE NOTES
--
1. INSPECT BMPs EACH WORKDAY. AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN SMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. RILL EROSION OCCURRING ON TERRACED SLOPES SHALL BE REPAIRED, RESEEDED.
MULCHED OR STABILIZED IN A MANNER APPROVED BY LOCAL JURISDICTION.
5. TERRACING MAY NEED TO BE RE-GRADED TO RETURN THE SLOPE TO THE FINAL DESIGN
GRADE. THE SLOPE SHALL THEN BE COVERED WITH TOPSOIL, SEEDED AND MULCHED, OR
OTHERWISE STABILIZED AS APPROVED BY LOCAL JURISDICTION.
(DETAIL ADAPTED fROM DOUGLAS COUNTY, COLORADO ANO TOWN Of" PARKER, COLORADO, NOT AVAILABLE IN AUTOCAD)
llillE;. MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Check Dams (CD) EC-12
Description
Check dams arc temporary grade control
structures placed in drainage channels to
limit the crosivity of stormwater by
reducing flow velocity. Check dams arc
typically constructed from rock, gravel
bags, sand bags, or sometimes,
proprietary devices. Reinforced check
dams are typically constructed from rock
and wire gabion. Although the primary
function of check dams is to reduce the
velocity of concentrated flows, a
secondary benefit is sediment trapping
upstream of the structure.
Photograph CD-I. Rock check dams in a roadside ditch. Photo
courtesy ofWWE.
Appropriate Uses
Use as a grade control for temporary drainage ditches or swales until final soil stabilization measures are
established upstream and downstream. Check dams can be used on mild or moderately steep slopes.
Check dams may be used under the following conditions:
•
•
•
As temporary grade control facilities along waterways until final stabilization is established .
Along permanent swales that need protection prior to installation of a non-erodible lining .
Along temporary channels, ditches or swales that need protection where construction of a non-
erodible lining is not practicable.
• Reinforced check dams should be used in areas subject to high flow velocities.
Design and Installation
Place check dams at regularly spaced intervals along the drainage swale or ditch. Check dams heights
should allow for pools to develop upstream of each check dam, extending to the downstream toe of the
check dam immediately upstream.
When rock is used for the check dam, place rock mechanically or by hand. Do not dump rocks into the
drainage channel. Where multiple check dams are used, the top of the lower dam should be at the same
elevation as the toe of the upper dam.
When reinforced check dams are used, install erosion control fabric under and around the check dam to
prevent erosion on the upstream and downstream sides. Each
section of the dam should be keyed in to reduce the potential
for washout or undermining. A rock apron upstream and
downstream of the dam may be necessary to further control
eros10n.
Check Dams
· Functions
Erosion Control
Sediment Control
Site/Material Management
November 20 I 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Yes
Moderate
No
CD-I
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EC-12 Check Dams (CD)
Design details with notes are provided for the following types of check dams:
• Rock Check Dams (CD-I)
• Reinforced Check Dams (CD-2)
Sediment control logs may also be used as check dams; however, silt fence is not appropriate for use as a
check dam. Many jurisdictions also prohibit or discourage use of straw bales for this purpose.
Maintenance and Removal
Replace missing rocks causing voids in the check dam. If gravel bags or sandbags are used, replace or
repair tom or displaced bags.
Remove accumulated sediment, as needed to maintain BMP effectiveness, typically before the sediment
depth upstream of the check dam is within ½ of the crest height. Remove accumulated sediment prior to
mulching, seeding, or chemical soil stabilization. Removed sediment can be incorporated into the
earthwork with approval from the Project Engineer, or disposed of at an alternate location in accordance
with the standard specifications.
Check dams constructed in permanent swales should be removed when perennial grasses have become
established, or immediately prior to installation of a non-erodible lining. All of the rock and accumulated
sediment should be removed, and the area seeded and mulched, or otherwise stabilized.
CD-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Check Dams (CD) EC-12
COMPACTED J
BACKFILL,
(TYP.)
SECTION
8 TYP.
CHANNEL GRADE
UPSTREAM AND
DOWNSTREAM
LENGTH, L
CREST LENGTH, CL
SECTION
A
1' 6"
(MIN)
TOP OF CHECK DAM
CHECK DAM ELEVATION VIEW
2'
1' 6" _
FLOW -MIN.
1' MIN. -
--
2" RIPRAP, TYPE M OR D50 = l
TYPE L D50= 9" (SEE TABLE
MD-7, MAJOR DRAINAGE, VOL. 1
FOR GRADATION)
' I
:I
..
6'
~
.,
SECTION A
a·
C HANNEL
ADE ~ GR
EXCA VATION TO NEAT
LINE,
(TYP.
AVOID OVER-EXCAVATION,
)
FLOW_=--~==~==~==-__L ~HANNEL GRADE
,· ,,,!-~ "~""" ro "~' L"'"""""'""""'"""''"""""""""""'""'-= LINE, AVOID OVER-EXCAVATION
050 -12" RIPRAP, TYPE M OR (TYP.)
TYPE L 050=9" (SEE TABLE MD-7,
MAJOR DRAINAGE, VOL. 1 FOR
GRADATION) SECTION B
I SPACING BETWEEN CHECK DAMS SUCH TIHAT I
_ A ANO B ARE EQUAL ELEVATION
--------. B
CHANNEL GRADE _/ ---~ -
PROFILE .
November 2010
CD-1. CHECK DAM
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
CD-3
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EC-12 Check Dams (CD)
CD-4
CHECK DAM INSTAI I ATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATION OF CHECK DAMS.
-CHECK DAM TYPE (CHECK DAM OR REINFORCED CHECK DAM).
-LENGTH (L), CREST LENGTH (CL), AND DEPTH (D).
2. CHECK DAMS INDICATED ON INlllAL SWMP SHALL BE INSTALLED AFTER CONSTRUCTION
FENCE, BUT PRIOR TO ANY UPSTREAM LAND DISTURBING ACTIVITIES.
J. RIPRAP UTILIZED FOR CHECK DAMS SHOULD BE OF APPROPRIATE SIZE FOR THE
APPLICATION. TYPICAL TYPES OF RIPRAP USED FOR CHECK ·DAMS ARE TYPE M (050 12")
OR TYPE L (050 9").
4. RIPRAP PAO SHALL BE TRENCHED INTO THE GROUND A MINIMUM OF I'.
5. THE ENDS OF THE CHECK DAM SHALL BE A MINIMUM OF 1' 6" HIGHER THAN THE CENTER
OF THE CHECK DAM.
CHECK DAM MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE AIRE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
J. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. SEDIMENT ACCUMULATED UPSTREAM OF THE CHECK DAMS SHALL BE REMOVED WHEN THE
SEDIMENT DEPTH IS WITHIN Ji OF THE HEIGHT OF THE CREST.
5. CHECK DAMS AIRE TO REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AIREA IS
STABILIZED AND APPROVED BY THE LOCAL JURISDICTION.
6. WHEN CHECK DAMS ARE REMOVED, EXCAVATIONS SHALL BE FILLED WITH SUITABLE
COMPACTED BACKFILL. DISTURBED AREA SHALL BE SEEDED AND MULCHED ANO COVERED WITH
GEOTEXTILE OR OTHERWISE STABILIZED IN A MANNER APPROVED BY THE LOCAL JURISDICTION.
(DETAILS ADAPTED FROt.l DOUGLAS COUNTY, COLORADO, NOT AVAILABLE IN AUTOCAD)
llilIE;. MANY JURISDICTIONS HAYE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Check Dams (CD) EC-12
ALTERNATIVE TO STEPS ON BANKS ABOVE CREST:
DEFORM GABIONS AS NECESSARY TO ALIGN TOP OF GABIONS
WITH GROUND SURFACE: AVOID GAPS BETWEEN GABIONS 8
MAX. STEP
HEIGHT 1 '6"
LENGTH L
CREST LENGTH CL
ll?-,t-,,:::::-.--;-Q.6'-L!.t'.../
COMPACTED _/
BACKFILL HOG
ROCK FILLED GABION
SECURED TO
ADJACENT GABION
REINFORCED CHECK DAM ELEVATION VIEW
3'
1'6"
050-6" RIPRAP
ENCLOSED IN GABION
1 '6" 6" MIN.
MIN FLOW --,;==;:;$
1 ·sij; ~ T -L CHANNEL GRADE
COMPACTED BACKFILL __.-!-•< ''')'' '' ,,v,,l .. ,,~ GEOTEXTlLE BLANKET
SECTION A
REINFORCED CHECK DAM INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATIONS OF CHECK DAMS.
-CHECK DAM TYPE (CHECK DAM OR REINFORCED CHECK DAM).
-LENGTH (L). CREST LENGTH (CL), AND DEPTH (D).
2. CHECK DAMS INDICATED ON THE SWMP SHALL BE INSTALLED PRIOR TO AN UPSTREAM
LANO-DISTURBING ACTMTIES.
J. REINFORCED CHECK DAMS, GABIDNS SHALL HAVE GALVANIZED TWISTED WIRE NETTING
WITH A MAXIMUM OPENING DIMENSION OF 4)f' AND A MINIMUM WIRE THICKNESS OF 0. 10".
WIRE "HOG RINGS" AT 4" SPACING OR OTHER APPROVED MEANS SHALL BE USED AT ALL
GABION SEAMS AND TO SECURE THE GABION TO THE ADJACENT SECTION.
4. THE CHECK DAM SHALL BE TRENCHED INTO THE GROUND A MINIMUM OF 1' 6".
5. GEOTEXTILE BLANKET SHALL BE PLACED IN THE REINFORCED CHECK DAM TRENCH
EXTENDING A MINIMUM OF 1' 6" ON BOTH THE UPSTREAM ANO DOWNSTREAM SIDES OF THE
REINFORCED CHECK DAM.
November 2010
CD-2. REINFORCED CHECK DAM
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
CD-5
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EC-12 Check Dams (CD)
CD-6
REINFORCED CHECK DAM MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs PS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE 8MPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD SE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. SEDIMENT ACCUMULATED UPSTREAM OF REINFORCED CHECK DAMS SHALL SE REMOVED AS
NEEDED TO MAINTAIN THE EFFECTIVENESS OF BMP, TYPICALLY WHEN THE UPSTREAM SEDIMENT
DEPTH IS WITHIN JI, THE HEIGHT OF THE CREST.
5. REPAIR OR REPLACE REINFORCED CHECK DAMS WHEN THERE ARE SIGNS OF DAMAGE SUCH
AS HOLES IN THE GA810N OR UNDERCUTTING.
6. REINFORCED CHECK DAMS ARE TO REMAIN IN PLACE UNTIL THE UPSTREAIV DISTURBED
AREA IS STABILIZED AND APPROVED SY THE LOCAL JURISDICTION.
7. WHEN REINFORCED CHECK DAMS ARE REMOVED, ALL DISTURBED AREAS SHALL BE
COVERED WITH TOPSOIL, SEEDED AND MULCHED, AND COVERED WITH A GEOTEXTILE BLANKET,
OR OTHERWISE STABILIZED AS APPROVED SY LOCAL JURISDICTION.
(DETAIL ADAPTED FROM DOUGLAS COUNTY, COLORADO ANO CITY Of NJRORA, COLORADO. NOT AVAILABLE IN AUTOCAO)
llil]L MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD SE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Wind Erosion/Dust Control (DC) EC-14
Description
Wind erosion and dust control BMPs
help to keep soil particles from entering
the air as a result of land disturbing
construction activities. These BMPs
include a variety of practices generally
focused on either graded disturbed areas
or construction roadways. For graded
areas, practices such as seeding and
mulching, use of soil binders, site
watering, or other practices that provide
prompt surface cover should be used.
For construction roadways, road
watering and stabilized surfaces should
be considered. Photograph DC·l. Water truck used for dust suppression. Photo
courtesy of Douglas County.
Appropriate Uses
Dust control measures should be used on any site where dust poses a problem to air quality. Dust control
is important to control for the health of construction workers and surrounding waterbodies.
Design and Installation
The following construction BMPs can be used for dust control:
■ An irrigation/sprinkler system can be used to wet the top layer of disturbed soil to help keep dry soil
particles from becoming airborne.
■
■
Seeding and mulching can be used to stabilize disturbed surfaces and reduce dust emissions.
Protecting existing vegetation can help to slow wind velocities across the ground surface, thereby
limiting the likelihood of soil particles to become airborne.
■ Spray-on soil binders form a bond between soil particles keeping them grounded. Chemical
treatments may require additional permitting requirements. Potential impacts to surrounding
waterways and habitat must be considered prior to use.
• Placing rock on construction roadways and entrances will help keep dust to a minimum across the
construction site.
• Wind fences can be installed on site to reduce wind
speeds. Install fences perpendicular to the prevailing
wind direction for maximum effectiveness.
Wind Erosion Control/
Maintenance and Removal
When using an irrigation/sprinkler control system to aid in
dust control, be careful not to overwater. Overwatering will
cause construction vehicles to track mud off-site.
Dust Control
Functions , · ,. ,' -,•"
Erosion Control
Sediment Control
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
. .,
C
Yes
No
Moderate
DC-I
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Concrete Washout Area (CWA)
Description
Concrete waste management involves
designating and properly managing a
specific area of the construction site as a
concrete washout area. A concrete
washout area can be created using one of
several approaches designed to receive
wash water from washing of tools and
concrete mixer chutes, liquid concrete
waste from dump trucks, mobile batch
mixers, or pump trucks. Three basic
approaches are available: excavation of a
pit in the ground, use of an above ground
storage area, or use of prefabricated haul-
away concrete washout containers.
Surface discharges of concrete washout
MM-1
water from construction sites are prohibited. Photograph CWA-1. Example of concrete washout area. Note gravel
tracking pad for access and sign.
Appropriate Uses
Concrete washout areas must be designated on all sites that will generate concrete wash water or liquid
concrete waste from onsite concrete mixing or concrete delivery.
Because pH is a pollutant of concern for washout activities, when unlined pits are used for concrete
washout, the soil must have adequate buffering capacity to result in protection of state groundwater
standards; otherwise, a liner/containment must be used. The following management practices are
recommended to prevent an impact from unlined pits to groundwater:
■ The use of the washout site should be temporary (less than 1 year), and
■ The washout site should be not be located in an area where shallow groundwater may be present, such
as near natural drainages, springs, or wetlands.
Design and Installation
Concrete washout activities must be conducted in a manner that does not contribute pollutants to surface
waters or stormwater runoff. Concrete washout areas may be lined or unlined excavated pits in the
ground, commercially manufactured prefabricated washout containers, or aboveground holding areas
constructed of berms, sandbags or straw bales with a plastic liner.
Although unlined washout areas may be used, lined pits may be required to protect groundwater under
certain conditions.
Do not locate an unlined washout area within 400 feet
of any natural drainage pathway or waterbody or
within 1,000 feet of any wells or drinking water
sources. Even for lined concrete washouts, it is
advisable to locate the facility away from waterbodies
and drainage paths. If site constraints make these
Concrete Washout Area
J/11nctiin1i -•· •_ .. '_f '·
'",} > .
Erosion Control
Sediment Control
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
No
No
Yes
CWA-1
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MM-1 Concrete Washout Area (CWA)
setbacks infeasible or if highly permeable soils exist in the area, then the pit must be installed with an
impermeable liner (16 mil minimum thickness) or surface storage alternatives using prefabricated
concrete washout devices or a lined aboveground storage area should be used.
Design details with notes arc provided in Detail CW A-1 for pits and CW A-2 for aboveground storage
areas. Pre-fabricated concrete washout container infonnation can be obtained from vendors.
Maintenance and Removal
A key consideration for concrete washout areas is to ensure that adequate signage is in place identifying
the location of the washout area. Part of inspecting and maintaining washout areas is ensuring that
adequate signage is provided and in good repair and that the washout area is being used, as opposed to
washout in non-designated areas of the site.
Remove concrete waste in the washout area, as needed to maintain BMP function (typically when filled to
about two-thirds of its capacity). Collect concrete waste and deliver offsite to a designated disposal
location.
Upon termination of use of the washout site, accumulated solid waste, including concrete waste and any
contaminated soils, must be removed from the site to prevent on-site disposal of solid waste. If the wash
water is allowed to evaporate and the concrete hardens, it may be recycled.
Photograph CWA-2. Prefabricated concrete washout. Photo
courtesy ofCDOT.
Photograph CWA-3. Earthen concrete washout. Photo
courtesy ofCDOT.
CWA-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Concrete Washout Area (CWA) MM-1
~ CONCRETE WASHOUT
YSIGN
~ " -~"-Ml-Q ~ / "".""'c'"'. ::!.-1
, ¾4tj;~t( 3:1 J ~~N .. ~
rl'J'ry,·~-
8
" ~
f ~v
3:1 8 X 8 MIN. 3:1
.
> j. .. ,) .,
"" 0
VEHICLE TRACKING
CONTROL (SEE
VTC DETAIL) OR
OTHER STABLE
SURFACE
/ ~ V 3:1
~ 25 MIN.
CONCRETE WASHOUT AREA PLAN
12" TYP. COMPACTED BERM AROUND
THE PERIMETER
1L..:::::::
?3
J' MIN.
X 8 MIN.
SECTION A
2% SLOPE
-----'1 ~~~%~~<f ~~ :...____J /,--, /)/'.,,;{/,-.1/,,Y/ .. /~,-
>J
VEHICLE TRACKING
CONTROL {SEE VTC
DETAJL )
CWA-1. CONCRETE WASHOUT AREA
CWA INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-CWA INSTALLATION LOCATION.
2. DO NOT LOCATE AN UNLINED CWA WITHIN 400' OF ANY NATURAL DRAINAGE PATHWAY OR
WATERBODY. DO NOT LOCATE WITHIN 1,000' OF ANY WELLS OR DRINKING WATER SOURCES. IF
SITE CONSTRAJNTS MAKE THIS INFEASIBLE, OR IF HIGHLY PERMEABLE SOILS EXIST ON SITE,
THE CWA MUST BE INSTALLED WITH AN IMPERMEABLE LINER (16 MIL MIN. THICKNESS) OR
SURFACE STORAGE ALTERNATIVES USING PREFABRICATED CONCRETE WASHOUT DEVICES OR A
LINEO ABOVE GROUND STORAGE ARE SHOULD BE USED.
3. THE CWA SHALL BE INSTALLED PRIOR TO CONCRETE PLACEMENT ON SITE.
4. CWA SHALL INCLUDE A FLAT SUBSURFACE PIT THAT JS AT LEAST B' BY B' SLOPES
LEADING OUT OF THE SUBSURFACE PIT SHALL BE 3:1 OR FLATTER. THE PIT SHALL BE AT
LEAST 3' DEEP.
5. BERM SURROUNDING SIDES ANO BACK OF THE CWA SHALL HAVE MINIMUM HEIGHT OF 1 '.
6. VEHICLE TRACKING PAD SHALL BE SLOPED 2% TOWARDS THE CWA.
7. SIGNS SHALL BE PLACED AT THE CONSTRUCTION ENTRANCE, AT THE CWA, AND
ELSEWHERE AS NECESSARY TO CLEARLY INDICATE THE LOCATION OF THE CWA TO OPERATORS
OF CONCRETE TRUCKS AND PUMP RIGS.
8. USE EXCAVATED MATERIAL FOR PERIMETER BERM CONSTRUCTION.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
CWA-3
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MM-1 Concrete Washout Area (CWA)
CWA-4
CWA MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAJNTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAJLURE.
4. THE CWA SHALL BE REPAJRED, CLEANED, OR ENLARGED AS NECESSARY TO MAJNTAIN
CAPACITY FOR CONCRETE WASTE. CONCRETE MATERIALS, ACCUMULATED IN PIT, SHALL BE
REMOVED ONCE THE MATERIALS HAVE REACHED A DEPTH OF 2'.
5. CONCRETE WASHOUT WATER, WASTED PIECES OF CONCRETE AND ALL OTHER DEBRIS
IN THE SUBSURFACE PIT SHALL BE TRANSPORTED FROM THE JOB SITE IN A WATER-TIGHT
CONTAINER AND DISPOSED OF PROPERLY.
6. THE CWA SHALL REMAIN IN PLACE UNTIL ALL CONCRETE FOR THE PROJECT IS PLACED.
7. WHEN THE CWA IS REMOVED, COVER THE DISTURBED AREA WITH TOP SOIL, SEED AND
MULCH OR OTHERWISE STABILIZED IN A MANNER APPROVED BY THE LOCAL JURISDICTION.
(DETAIL AOio\PTtO FROM DOUGLAS COUNTY, COLORADO AND THE CITY or PARKER, COLORADO, NOT AVAllABtE IN AUTOCAO).
NOTE; MANY. JURISDICTIONS HAVE BMP DETNLS THAT VARY FROM UDFCD STANDARD DETNLS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Stockpile Management (SP) MM-2
Description
Stockpile management includes
1neasures to minimize erosion and
sediment transport from soil stockpiles.
Appropriate Uses
Stockpile management should be used
when soils or other erodible materials
are stored at the construction site.
Special attention should be given to
stockpiles in close proximity to natural
or manmade storm systems.
Design and Installation
Photograph SP-1. A topsoil stockpile that has been partially
revegetated and is protected by silt fence perimeter control.
Locate stockpiles away from all drainage system components including storm sewer inlets. Where
practical, choose stockpile locations that that will remain undisturbed for the longest period of time as the
phases of construction progress. Place sediment control BMPs around the perimeter of the stockpile, such
as sediment control logs, rock socks, silt fence, straw bales and sand bags. See Detail SP-I for guidance
on proper establishment of perimeter controls around a stockpile. For stockpiles in active use, provide a
stabilized designated access point on the upgradient side of the stockpile.
Stabilize the stockpile surface with surface roughening, temporary seeding and mulching, erosion control
blankets, or soil binders. Soils stockpiled for an extended period (typically for more than 60 days) should
be seeded and mulched with a temporary grass cover once the stockpile is placed (typically within 14
days). Use of mulch only or a soil binder is acceptable if the stockpile will be in place for a more limited
time period (typically 30-60 days). Timeframes for stabilization of stockpiles noted in this fact sheet are
"typical" guidelines. Check permit requirements for specific federal, state, and/or local requirements that
may be more prescriptive.
Stockpiles should not be placed in streets or paved areas unless no other practical alternative exists. See
the Stabilized Staging Area Fact Sheet for guidance when staging in roadways is unavoidable due to
space or right-of-way constraints. For paved areas, rock socks must be used for perimeter control and all
inlets with the potential to receive sediment from the stockpile (even from vehicle tracking) must be
protected.
Maintenance and Removal
Inspect perimeter controls and inlet protection in accordance with their respective BMP Fact Sheets.
Where seeding, mulch and/or soil binders are used, reseeding or reapplication of soil binder may be
necessary.
When temporary removal of a perimeter BMP is necessary
to access a stockpile, ensure BMPs are reinstalled in
accordance with their respective design detail section.
Stockpile Management
November 20 I 0
Fu.~ctions: ',"< ·' -;,-~ ,C,, :,-.:,
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
' ----, ·:/.i: ·•►: -' ·-_ /.•' 1,
Yes
Yes
Yes
SP-I
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MM-2 Stockpile Management (SM)
When the stockpile is no longer needed, properly dispose of excess materials and revegetate or otherwise
stabilize the ground surface where the stockpile was located.
SP-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Stockpile Management (SP) MM-2
0
MIN
STOCKPILE
I ~ / \ ----<-SILT FENCE (SEE SF DETAIL FOR
"" --------/-----INSTALLATION REQUIREMENTS) ......___ ___
STOCKPILE PROTECTION PLAN
MAXIMUM
2
1 r:; SILT FENCE (SEE SF DETAIL FOR
INSTALLATION REQUIREMENTS)
SECTION A
SP-1. STOCKPILE PROTECTION
STOCKPILE PROTECTION INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATION OF STOCKPILES.
-TYPE OF STOCKPILE PROTECTION.
2. INSTALL PERIMETER CONTROLS IN ACCORDANCE WITH THEIR RESPECTIVE DESIGN DETAILS.
SILT FENCE IS SHOWN IN THE STOCKPILE PROTECTION DETAILS: HOWEVER, OTHER TYPES OF
PERIMET!ER CONTROLS INCLUDING SEDIMENT CONTROL LOGS OR ROCK SOCKS MAY BE
SUITABLE IN SOME CIRCUMSTANCES. CONSIDERATIONS FOR DETERMINING THE APPROPRIATE
TYPE OF PERIMETER CONTROL FOR A STOCKPILE INCLUDE WHETHER THE STOCKPILE IS
LOCAT!ED ON A PERVIOUS OR IMPERVIOUS SURFACE, THE RELATIVE HEIGHTS OF THE
PERIMET!ER CONTROL AND STOCKPILE, THE ABILITY OF THE PERIMETER CONTROL TO CONTAIN
THE STOCKPILE WITHOUT FAILING IN THE EVENT THAT MATERIAL FROM THE STOCKPILE SHIFTS
OR SLUMPS AGAINST THE PERIMETER, ANO OTHER FACTORS.
3. STABILIZE THE STOCKPILE SURFACE WITH SURFACE ROUGHENING, TEMPORARY SEEDING AND
MULCHING, EROSION CONTROL BLANKETS, OR SOIL BINDERS. SOILS STOCKPILED FOR AN
EXTENDED PERIOD (TYPICALLY FOR MORE THAN 60 DAYS) SHOULD BE SEEDED ANO MULCHED
WITH A TEMPORARY GRASS COVER ONCE THE STOCKPILE IS PLACED (TYPICALLY WITHIN 14
DAYS). USE OF MULCH ONLY OR A SOIL BINDER IS ACCEPTABLE IF THE STOCKPILE WILL BE
IN PLACE FOR A MORE LIMITED TIME PERIOD (TYPICALLY 30-60 DAYS).
4. FOR TEMPORARY STOCKPILES ON THE INTERIOR PORTION OF A CONSTRUCTION SITE, WHERE
OTHER DOWNGRAOIENT CONTROLS, INCLUDING PERIMETER CONTROL, ARE IN PLACE, STOCKPILE
PERIMETER CONTROLS MAY NOT BE REQUIRED.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SP-3
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MM-2 Stockpile Management.(SM)
SP-4
STOCKPILE PROTECTJON MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
J. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
STOCKPILE PROTECTJON MAINTENANCE NOTES
4. IF PERIMETER PROTECTION MUST BE MOVED TO ACCESS SOIL STOCKPILE, REPLACE
PERIMETER CONTROLS BY THE END OF THE WORKDAY.
5. STOCKPILE PERIMETER CONTROLS CAN BE REMOVED ONCE ALL THE MATERIAL FROM THE
STOCKPILE HAS BEEN USED.
(DETAILS AO-'PTEO FROM PARKER, COLORADO, NOT AVAILABLE IN AUTOCAO)
Nfil;, MANY JURISDICTIONS HAVE BMP DETAILS' THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITIH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 lO
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Stockpile Management (SP) MM-2
w~□
ORANGE SAFETY r
CONE
TARP ANCHOR
POLY LINER
BERM
POLY TARP
SOIL/LANDSCAPE
MATERIAL
6" PVC PIPE
IN FLOWLINE &FOR DRAINAGE
~--l-..l_--'===~=~=~===.-1----11----'f r CURB LINE
SP-2. MATERIALS STAGING IN ROADWAY
MATERIAi S STAGING IN RQAQWAY5 IN5JAI I AIIQN NOTES
1. SEE PLAN VIEW FOR
-LOCATION OF MATERIAL STAGING AREA(S).
-CONTRACTOR MAY ADJUST LOCATION AND SIZE OF STAGING AREA WITH APPROVAL
FROM THE LOCAL JURISDICTION.
2. FEATURE MUST BE INSTALLED PRIOR TO EXCAVATION, EARTHWORK OR DELIVERY OF
MATERIALS.
J. MATERIALS MUST BE STATIONED ON THE POLY LINER. ANY INCIDENTAL MATERIALS
DEPOSITED ON PAVED SECTION OR ALONG CURB LINE MUST BE CLEANED UP PROMPTLY.
4. POLY LINER AND TARP COVER SHOULD BE OF SIGNIFICANT THICKNESS TO PREVENT
DAMAGE OR LOSS OF INTEGRITY.
5. SAND BAGS MAY BE SUBSTITUTED TO ANCHOR THE COVER TARP OR PROVlDE BERMING
UNDER THE BASE LINER.
6. FEATURE IS NOT INTENDED FOR USE WITH WET MATERIAL THAT WILL BE DRAINING AND/OR
SPREADING OUT ON THE POLY LINER OR FOR DEMOLITION MATERIALS.
7. THIS FEATURE CAN BE USED FOR:
November 2010
-UTILITY REPAIRS.
-WHEN OTHER STAGING LOCATIONS AND OPTIONS ARE LIMITED.
-OTHER LIMITED APPLICATION AND SHORT DURATION STAGING.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SP-5
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MM-2 Stockpile Management (SM)
SP-6
MATERIAi S STAGING IN ROADWAY MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECflONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
J. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. INSPECT PVC PIPE ALONG CURB LINE FOR CLOGGING AND DEBRIS. REMOVE OBSTRUCTIONS
PROMPTLY.
5. CLEAN MATERIAL FROM PAVED SURFACES BY SWEEPING OR VACUUMING.
llilIE;. MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
(DETAILS ADAPTED F'ROM AURORA, COLORADO)
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Good Housekeeping Practices (GH) MM-3
Description
Implement construction site good housekeeping practices to
prevent pollution associated with solid, liquid and hazardous
construction-related materials and wastes. Stormwater
Management Plans (SWMPs) should clearly specify BMPs
including these good housekeeping practices:
• . Provide for waste management.
• Establish proper building material staging areas.
• Designate paint and concrete washout areas.
• Establish proper equipment/vehicle fueling and
maintenance practices.
• Control equipment/vehicle washing and allowable non-
stormwater discharges.
• Develop a spill prevention and response plan.
Acknowledgement: This Fact Sheet is based directly on
EPA guidance provided in Developing Your Stormwater
Pollution Prevent Plan (EPA 2007).
Appropriate Uses
Photographs GH-1 and GH-2. Proper materials
storage and secondary containment for fuel tanks
are important good housekeeping practices. Photos
courtesy ofCDOT and City of Aurora.
Good housekeeping practices are necessary at all construction sites.
Design and Installation
The following principles and actions should be addressed in SWMPs:
■ Provide for Waste Management. Implement management procedures and practices to prevent or
reduce the exposure and transport of pollutants in stormwater from solid, liquid and sanitary wastes
that will be generated at the site. Practices such as trash disposal, recycling, proper material handling,
and cleanup measures can reduce the potential for stormwater runoff to pick up construction site
wastes and discharge them to surface waters. Implement a comprehensive set of waste-management
practices for hazardous or toxic materials, such as paints, solvents, petroleum products, pesticides,
wood preservatives, acids, roofing tar, and other materials. Practices should include storage,
handling, inventory, and cleanup procedures, in case of spills. Specific practices that should be
considered include:
Solid or Construction Waste Good Housekeeping
o Designate trash and bulk waste-collection areas on-
site.
Ftln~ti6ns · ;• ·
Erosion Control
Sediment Control
/ .r· ...
Site/Material Management
November 201 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
.. ' ·. •', C
No
No
Yes
GH-1
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MM-3 Good Housekeeping Practices (GH)
o Recycle materials whenever possible (e.g., paper, wood, concrete, oil).
o Segregate and provide proper disposal options for hazardous material wastes.
o Clean up litter and debris from the construction site daily.
o Locate waste-collection areas away from streets, gutters, watercourses, and storm drains. Waste-
collection areas ( dumpsters, and such) are often best located near construction site entrances to
minimize traffic on disturbed soils. Consider secondary containment around waste collection
areas to minimize the likelihood of contaminated discharges.
o Empty waste containers before they are full and overflowing.
Sanitary and Septic Waste
o Provide convenient, well-maintained, and properly located toilet facilities on-site.
o Locate toilet facilities away from storm drain inlets and waterways to prevent accidental spills
and contamination of stormwater.
o Maintain clean restroom facilities and empty portable toilets regularly.
o Where possible, provide secondary containment pans under portable toilets.
o . Provide tie-downs or stake-downs for portable~oilets.
o Educate employees, subcontractors, and suppliers on locations of facilities.
o Treat or dispose of sanitary and septic waste in accordance with state or local regulations. Do not
discharge or bury wastewater at the construction site.
o Inspect facilities for leaks. If found, repair or replace immediately.
o Special care is necessary during maintenance (pump out) to ensure that waste and/or biocide are
not spilled on the ground.
Hazardous Materials and Wastes
o Develop and implement employee and
subcontractor education, as needed, on
hazardous and toxic waste handling,
storage, disposal, and cleanup.
o Designate hazardous waste-collection
areas on-site.
o Place all hazardous and toxic material
wastes in secondary containment.
Photograph GH-3. Locate portable toilet facilities on level
surfaces away from waterways and storm drains. Photo
courtesy of WWE.
GH-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Good Housekeeping Practices (GH) MM-3
o Hazardous waste containers should be inspected to ensure that all containers arc labeled properly
and that no leaks arc present.
• Establish Proper Building Material Handling and Staging Areas. The SWMP should include
comprehensive handling and management procedures for building materials, especially those that are
hazardous or toxic. Paints, solvents, pesticides, fuels and oils, other hazardous materials or building
materials that have the potential to contaminate stormwater should be stored indoors or under cover
whenever possible or in areas with secondary containment. Secondary containment measures prevent
a spill from spreading across the site and may include dikes, berms, curbing, or other containment
methods. Secondary containment techniques should also ensure the protection of groundwater.
Designate staging areas for activities such as fueling vehicles, mixing paints, plaster, mortar, and
other potential pollutants. Designated staging areas enable easier monitoring of the use of materials
and clean up of spills. Training employees and subcontractors is essential to the success of this
pollution prevention principle. Consider the following specific materials handling and staging
practices:
o Train employees and subcontractors in proper handling and storage practices.
o Clearly designate site areas for staging and storage with signs and on construction drawings.
Staging areas should be located in areas central to the construction site. Segment the staging area
into sub-areas designated for vehicles, equipment, or stockpiles. Construction entrances and exits
should be clearly marked so that delivery vehicles enter/exit through stabilized areas with vehicle
tracking controls (See Vehicle Tracking Control Fact Sheet).
o Provide storage in accordance with Spill Protection, Control and Countermeasures (SPCC)
requirements and plans and provide cover and impermeable perimeter control, as necessary, for
hazardous materials and contaminated soils that must be stored on site.
o Ensure that storage containers are regularly inspected for leaks, corrosion, support or foundation
failure, or other signs of deterioration and tested for soundness.
o Reuse and recycle construction materials when possible.
• Designate Concrete Washout Areas. Concrete contractors should be encouraged to use the washout
facilities at their own plants or dispatch facilities when feasible; however, concrete washout
commonly occurs on construction sites. If it is necessary to provide for concrete washout areas on-
site, designate specific washout areas and design facilities to handle anticipated washout water.
Washout areas should also be provided for paint and stucco operations. Because washout areas can
be a source of pollutants from leaks or spills, care must be taken with regard to their placement and
proper use. See the Concrete Washout Area Fact Sheet for detailed guidance.
Both self-constructed and prefabricated washout containers can fill up quickly when concrete, paint,
and stucco work are occurring on large portions of the site. Be sure to check for evidence that
contractors are using the washout areas and not dumping materials onto the ground or into drainage
facilities. If the washout areas are not being used regularly, consider posting additional signage,
relocating the facilities to more convenient locations, or providing training to workers and
contractors.
When concrete, paint, or stucco is part of the construction process, consider these practices which will
help prevent contamination of stormwater. Include the locations of these areas and the maintenance
and inspection procedures in the SWMP.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
GH-3
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MM-3 Good Housekeeping Practices (GH)
•
•
o Do not washout concrete tlucks or equipment into storm drains, streets, gutters, uncontaincd
areas, or streams. Only use designated washout areas.
o Establish washout areas and advertise their locations with signs. Ensure that signage remains in
good repair.
o Provide adequate containment for the amount of wash water that will be used.
o Inspect washout structures daily to detect leaks or tears and to identify when materials need to be
removed ..
o Dispose of materials properly. The preferred method is to allow the water to evaporate and to
recycle the hardened concrete. Full service companies may provide dewatering services and
should dispose of wastewater properly. Concrete wash water can be highly polluted. It should
not be discharged to any surface water, storm sewer system, or allowed to infiltrate into the
ground in the vicinity ofwaterbodies. Washwater should not be discharged to a sanitary sewer
system without first receiving written permission from the system operator.
Establish Proper Equipment/Vehicle Fueling and Maintenance Practices. Create a clearly
designated on-site fueling and maintenance area that is clean and dry. The on-site fueling area should
have a spill kit, and staff should know how to use it. If possible, conduct vehicle fueling and
maintenance activities in a covered area. Consider the following practices to help prevent the
discharge of pollutants to stormwater from equipment/vehicle fueling and maintenance. Include the
locations of designated fueling and maintenance areas and inspection and maintenance procedures in
the SWMP.
o Train employees and subcontractors in proper fueling procedures (stay with vehicles during
fueling, proper use of pumps, emergency shutoff valves, etc.).
o Inspect on-site vehicles and equipment regularly for leaks, equipment damage, and other service
problems.
o Clearly designate vehicle/equipment service areas away from drainage facilities and watercourses
to prevent stormwater run-on and runoff.
o Use drip pans, drip cloths, or absorbent pads when replacing spent fluids.
o Collect all spent fluids, store in appropriate labeled containers in the proper storage areas, and
recycle fluids whenever possible.
Control Equipment/Vehicle Washing and Allowable Non-Stormwater Discharges. Implement
practices to prevent contamination of surface and groundwater from equipment and vehicle wash
water. Representative practices include:
o Educate employees and subcontractors on proper washing procedures.
o Use off-site washing facilities, when available.
o Clearly mark the washing areas and inform workers that all washing must occur in this area.
o Contain wash water and treat it using BMPs. Infiltrate washwater when possible, but maintain
separation from drainage paths and waterbodies.
GH-4 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Good Housekeeping Practices (GH) MM-3
o Use high-pressure water spray at vehicle washing facilities without detergents. Water alone can
remove most dirt adequately.
o Do not conduct other activities, such as vehicle repairs, in the wash area.
o Include the location of the washing facilities and the inspection and maintenance procedures in
the SWMP.
• Develop a Spill Prevention and Response Plan. Spill prevention and response procedures must be
identified in the SWMP. Representative procedures include identifying ways to reduce the chance of
spills, stop the source of spills, contain and clean up spills, dispose of materials contaminated by
spills, and train personnel responsible for spill prevention and response. The plan should also specify
material handling procedures and storage requirements and ensure that clear and concise spill cleanup
procedures are provided and posted for areas in which spills may potentially occur. When developing
a spill prevention plan, include the following:
o Note the locations of chemical storage areas, storm drains, tributary drainage areas, surface
waterbodies on or near the site, and measures to stop spills from leaving the site.
o Provide proper handling and safety procedures for each type of waste. Keep Material Safety Data
Sheets (MSDSs) for chemical used on site with the SWMP.
o Establish an education program for employees and subcontractors on the potential hazards to
humans and the environment from spills and leaks.
o Specify how to notify appropriate authorities, such as police and fire departments, hospitals, or
municipal sewage treatment facilities to request assistance. Emergency procedures and contact
numbers should be provided in the SWMP and posted at storage locations.
o Describe the procedures, equipment and materials for immediate cleanup of spills and proper
disposal.
o Identify personnel responsible for implementing the plan in the event of a spill. Update the spill
prevention plan and clean up materials as changes occur to the types of chemicals stored and used
at the facility.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
GH-5
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MM-3 Good Housekeeping Practices (GH)
Spill Prevention, Control, and Countermeasure (SPCC) Plan
Construction sites may be subject to 40 CFR Part 112 regulations that require the preparation and
implementation of a SPCC Plan to prevent oil spills from aboveground and underground storage tanks.
The facility is subject to this rule if it is a non-transportation-related facility that:
• Has a total storage capacity greater than 1,320 gallons or a completely buried storage capacity
greater than 42,000 gallons.
• Could reasonably be expected to discharge oil in quantities that may be hannful to navigable waters·
of the United States and adjoining shorelines.
Furthermore, if the facility is subject to 40 CFR Part 112, the SWMP should reference the SPCC Plan.
To find out more about SPCC Plans, see EPA's website on SPPC at www.epa.gov/oilspill/spcc.htm.
Reporting Oil Spills
In the event of an oil spill, contact the National Response Center toll free at 1-800-424-8802 for
assistance, or for more details, visit their website: www.nrc.uscg.mil.
Maintenance and Removal
Effective implementation of good housekeeping practices is dependent on clear designation of personnel
responsible for supervising and implementing good housekeeping programs, such as site cleanup and
disposal of trash and debris, hazardous material management and disposal, vehicle and equipment
maintenance, and other practices. Emergency response "drills" may aid in emergency preparedness.
Checklists may be helpful in good housekeeping efforts.
Staging and storage areas require permanent stabilization when the areas are no longer being used for
construction-related activities.
Construction-related materials, debris and waste must be removed from the construction site once
construction is complete.
Design Details
See the following Fact Sheets for related Design Details:
MM-I Concrete Washout Area
MM-2 Stockpile Management
SM-4 Vehicle Tracking Control
Design details are not necessary for other good housekeeping practices; however, be sure to designate
where specific practices will occur on the appropriate construction drawings.
GH-6 Urban Drainage and Flood Control District
Urban Stonn Drainage Criteria Manual Volume 3
November 2010
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Silt Fence (SF) SC-1
Description
A silt fence is a woven geotextile fabric
attached to wooden posts and trenched
into the ground. It is designed as a
sediment barrier to intercept sheet flow
runoff from disturbed areas.
Appropriate Uses
A silt fence can be used where runoff is
conveyed from a disturbed area as sheet
flow. Silt fence is not designed to
receive concentrated flow or to be used
as a filter fabric. Typical uses include:
• Down slope of a disturbed area to
accept sheet flow.
• Along the perimeter of a receiving
water such as a stream, pond or
wetland.
• At the perimeter of a construction site.
Design and Installation
Photograph SF-1. Silt fence creates a sediment barrier, forcing
sheet flow runoff to evaporate or infiltrate.
Silt fence should be installed along the contour of slopes so that it intercepts sheet flow. The maximum
recommended tributary drainage area per I 00 lineal feet of silt fence, installed along the contour, is
approximately 0.25 acres with a disturbed slope length ofup to 150 feet and a tributary slope gradient no
steeper than 3:1. Longer and steeper slopes require additional measures. This recommendation only
applies to silt fence installed along the contour. Silt fence installed for other uses, such as perimeter
control, should be installed in a way that will not produce concentrated flows. For example, a "J-hook"
installation may be appropriate to force runoff to pond and evaporate or infiltrate in multiple areas rather
than concentrate and cause erosive conditions parallel to the silt fence.
See Detail SF-1 for proper silt fence installation, which involves proper trenching, staking, securing the
fabric to the stakes, and backfilling the silt fence. Properly installed silt fence should not be easily pulled
out by hand and there should be no gaps between the ground and the fabric.
Silt fence must meet the minimum allowable strength requirements, depth of installation requirement, and
other specifications in the design details. Improper installation
of silt fence is a common reason for silt fence failure; however,
when properly installed and used for the appropriate purposes, it
can be highly effective.
Silt Fence
·:F~llctl~~s}-. .•.
Erosion Control
Sediment Control
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
''. ~-
No
Yes
No
SF-1
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SC-1
Maintenance and Removal
Inspection of silt fence includes observing the
material for tears or holes and checking for slumping
fence and undercut areas bypassing flows. Repair of
silt fence typically involves replacing the damaged
section with a new section. Sediment accumulated
behind silt fence should be removed, as needed to
maintain BMP effectiveness, typically before it
reaches a depth of 6 inches.
Silt fence may be removed when the upstream area
has reached final stabilization.
Silt Fence (SF)
Photograph SF-2. When silt fence is not installed along
the contour, a "}-hook" installation may be appropriate
to ensure that the BMP does not create concentrated
flow parallel to the silt fence. Photo courtesy of Torn
Gore.
SF-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 l 0
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Silt Fence (SF) SC-1
t½"xl½" 0F
(RECOMMENDED) WOODEN r FENCE POST WITH 10' MAX
SPACING
SILT FENCE
GEOTEXTILE ~
COMPACTED
BACKFILL
FJ.QW -
EXISTINJ--I~
GROUND
6" MIN
AT LEAST 10"
OF SILT FENCE
1~=1!! 18"
MIN
36"-48"
TYP.
"TAIL" SHALL BE 4" MIN
ROTATE
SECOND
JOIN
IRST
BURIED
POSTS SHALL BE JOINED AS
SHOWN, THEN ROTATED 180 DEG.
IN DIRECTION SHOWN AND DRIVEN
INTO THE GROUND
SILT FENCE
POSTS SHALL OVERLAP
AT JOINTS· SO THAT NO GAPS
EXIST IN SILT FENG
THICKNESS OF GEOTEXTILE HAS
BEEN EXAGGERATED, TYP
SECTION A
SF-1. SILT FENCE
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SF-3
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SC-1
SF-4
Silt Fence (SF)
sn I FENCE INSTAI IATION NO[ES
1. SILT FENCE MUST BE PLACED AWAY FROM THE TOE OF THE SLOPE TO ALLOW FOR WATER
PONDING. SILT FENCE AT THE TOE OF A SLOPE SHOULD BE INSTALLED IN A FLAT LOCATION
AT LEAST SEVERAL FEET (2-5 FT) FROM THE TOE OF THE SLOPE TO ALLOW ROOM FOR
PONDING AND DEPOSITION.
2. A UNIFORM 6" X 4" ANCHOR TRENCH SHALL BE EXCAVATED USING TRENCHER OR SILT
FENCE INSTALLATION DEVICE. NO ROAD GRADERS, BACKHOES, OR SIMILAR EQUIPMENT SHALL
BE USED.
3. COMPACT ANCHOR TRENCH BY HAND WITH A "JUMPING JACK" OR BY WHEEL ROLLING.
COMPACTION SHALL BE SUCH THAT SILT FENCE RESISTS BEING PULLED OUT OF ANCHOR
TRENCH BY HAND.
4. SILT FENCE SHALL BE PULLED TIGHT />S IT IS ANCHORED TO THE STAKES. THERE SHOULD
BE NO NOTICEABLE SAG BETWEEN STAKES AFTER IT HAS BEEN ANCHORED TO THE STAKES.
5. SILT FENCE FABRIC SHALL BE ANCHORED TO THE STAKES USING 1" HEAVY DUTY STAPLES
OR NAILS WITH 1" HEADS. STAPLES AND NAILS SHOULD BE PLACED 3" ALONG THE FABRIC
DOWN THE STAKE.
6. AT THE END OF A RUN OF SILT FENCE ALONG A CONTOUR, THE SILT FENCE SHOULD BE
TURNED PERPENDICULAR TO THE CONTOUR TO CREATE A "J-HOOK." THE "J-HOOK"
EXTENDING PERPENDICULAR TO THE CONTOUR SHOULD BE OF SUFFICIENT LENGTH TO KEEP
RUNOFF FROM FLOWING AROUND THE END OF THE SILT FENCE (TYPICALLY 10' -20').
7. SILT FENCE SHALL BE INSTALLED PRIOR TO ANY LAND DISTURBING ACTMTIES.
SILT FENCE MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. SEDIMENT ACCUMULATED UPSTREAM OF THE SILT FENCE SHALL BE REMOVED AS NEEDED
TO MAINTAIN THE FUNCTIONALITY OF THE BMP, TYPICALLY WHEN DEPTH OF ACCUMULATED
SEDIMENTS IS APPROXIMATELY 6".
5. REPAIR OR REPLACE SILT FENCE WHEN THERE ARE SIGNS OF WEAR, SUCH AS SAGGING,
TEARING, OR COLLAPSE.
6. SILT FENCE IS TO REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AREA IS STABILIZED
AND APPROVED BY THE LOCAL JURISDICTION, OR IS REPLACED BY AN EQUIVALENT PERIMETER
SEDIMENT CONTROL BMP.
7. WHEN SILT FENCE IS REMOVED, ALL DISTURBED AREAS SHALL BE COVERED WITH TOPSOIL,
SEEDED ANO MULCHED OR OTHERWISE STABILIZED />S APPROVED BY LOCAL JURISDICTION.
(DETAIL ADAPTED FROM TOWN OF PARKER, COLORADO ANO CITY OF AURORA, NOT AVAILABLE IN AUTOCAD)
NOTE: MANY JURISDICTIONS HAVE BMP DETAILS THIAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Sediment Control Log (SCL)
Description
A sediment control log is a linear roll
made of natural materials such as
straw, coconut fiber, or other fibrous
material trenched into the ground and
held with a wooden stake. Sediment
control logs are also often referred to
as "straw wattles." They are used as a
sediment barrier to intercept sheet flow
runoff from disturbed areas.
Appropriate Uses
Sediment control logs can be used in
the following applications to trap
sediment:
• As perimeter control for stockpiles
and the site.
• As part of inlet protection designs.
SC-2
• As check dams in small drainage
ditches. (Sediment control logs
are not intended for use in
channels with high flow
velocities.)
• On disturbed slopes to shorten flow
lengths (as an erosion control).
Photographs SCL-1 and SCL-2. Sediment control logs used as I) a
perimeter control around a soil stockpile; and, 2) as a "J-hook"
perimeter control at the comer of a construction site.
■ As part of multi-layered perimeter control along a receiving water such as a stream, pond or wetland.
Sediment control logs work well in combination with other layers of erosion and sediment controls.
Design and Installation
Sediment control logs should be installed along the contour to avoid concentrating flows. The maximum
allowable tributary drainage area per 100 lineal feet of sediment control log, installed along the contour, is
approximately 0.25 acres with a disturbed slope length of up to 150 feet and a tributary slope gradient no
steeper than 3: I. Longer and steeper slopes require additional measures. This recommendation only
applies to sediment control logs installed along the contour. When installed for other uses, such as
perimeter control, it should be installed in a way that will not
produce concentrated flows. For example, a "J-hook"
installation may be appropriate to force runoff to pond and
evaporate or infiltrate in multiple areas rather than concentrate
and cause erosive conditions parallel to the BMP.
Sediment Control Lo!!
November 2010
Furitti6its · · . . . -
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
'f .
-/' '
Moderate
Yes
No
SCL-1
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SC-2 Sediment Control Log (SCL)
Although sediment control logs initially allow runoff to flow through the BMP, they can quickly become
a barrier and should be installed is if they are impenncable.
Design details and notes for sediment control logs are provided in Detail SCL-1. Sediment logs must be
properly trenched and staked into the ground to prevent undercutting, bypassing and displacement. When
installed on slopes, sediment control logs should be installed along the contours (i.e., perpendicular to
flow).
Improper installation can lead to poor performance. Be sure that sediment control logs are properly
trenched, anchored and tightly jointed.
Maintenance and Removal
Be aware that sediment control logs will eventually degrade. Remove accumulated sediment before the
depth is one-half the height of the sediment log and repair damage to the sediment log, typically by
replacing the damaged section.
Once the upstream area is stabilized, remove and properly dispose of the logs. Areas disturbed beneath
the logs may need to be seeded and mulched. Sediment control logs that are biodegradable may
occasionally be left in place ( e.g., when logs are used in conjunction with erosion control blankets as
permanent slope breaks). However, removal of sediment control logs after final stabilization is typically
recommended when used in perimeter control, inlet protection and check dam applications.
SCL-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Sediment Control Log (SCL)
-SCl-SCL -SCL-
I½" x I½" x 18" (MIN)
WOODEN STAKE
9" DIAMETER (MIN)
SEDIMENT CONTROL LOG
SEDIMENT CONTROL LOG
L CENTER STAKE IN CONTROL LOG
COMPACTED EXCAVATED 3" 9" DIAMETER (MIN)
TRENCH SOIL T,;i'TTI"i,-,_--SEDIMENT CONTROL LOG
FLOW _ Y., DIAM. SCL (TYP.)
''\),:_;, ,,.,,~--~>i?:-<=?:<i?~%_, ',~%~~✓;¾,! _ _)~/{/' .
-~1✓
6"
SECTION A
12 .. OVERLAP
(MIN.)
1½'' x J½'' x 18" (MIN)
WOODEN STAKE
9" DIAMETER {MIN)
SEDIMENT CONTROL LOG
November 2010
SEDIMENT CONTROL LOG JOINTS
SCL-1. SEDIMENT CONTROL LOG
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SC-2
SCL-3
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SC-2 Sediment Control Log (SCL)
SCL-4
3" -
COMPACTED EXCAVATED I
CENTER STAKE IN CONTROL LOG
TRENCH SOIL ~
i-~-Hh.~-
FLOW -I
6" MIN.
9" DIAMETER (MIN)
-SEDIMENT CONTROL LOG
PLACE LOG AGAINST BACK OF CURB
~ DIAM. SCL (1YP.)
SCL-2. SEDIMENT CONTROL LOG AT BACK OF CURB
3" l._
CENTER STAKE
IN CONTROL LOG
9" DIAMETER (MIN)
SEDIMENT CONTROL LOG
½ DIAM. SCL (TYP.)
TREE LAWN (TYPICAL)
CURB
SCL-3. SEDIMENT CONTROL LOG AT SIDEWALK WITH
TREE LAWN
VERTICAL SPACING
ING
CONTINUOUS SCL
AT PERIMETER OF
CONSTRUCTION SITE
SCL-4. SEDIMENT CONTROL LOGS TO CONTROL
SLOPE LENGTH
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Sediment Control Log (SCL) SC-2
SEDIMENT CONTROL LOG INSTALLATION NOTES
1. SEE PLAN VIEW FOR LOCATION AND LENGTH OF SEDIMENT CONTROL LOGS.
2. SEDIMENT CONTROL LOGS THAT ACT AS A PERIMETER CONTROL SHALL BE INSTALLED PRIOR
TO ANY UPGRADIENT LAND-DISTURBING ACTIVITIES.
3. SEDIMENT CONTROL LOGS SHALL CONSIST OF STRAW, COMPOST, EXCELSIOR OR COCONUT
FIBER, ANO SHALL BE FREE OF ANY NOXIOUS WEED SEEDS OR DEFECTS INCLUDING RIPS,
HOLES AND OBVIOUS WEAR.
4. SEDIMENT CONTROL LOGS MAY BE USED AS SMALL CHECK DAMS IN DITCHES AND SWALES.
HOWEVER, THEY SHOULD NOT BE USED IN PERENNIAL STREAMS OR HIGH VELOCITY DRAINAGE
WAYS,
5. IT IS RECOMMENDED THAT SEDIMENT CONTROL LOGS BE TRENCHED INTO THE GROUND TO
A DEPTH OF APPROXIMATELY Y., OF THE DIAMETER OF THE LOG. IF TRENCHING TO THIS
DEPTH IS NOT FEASIBLE AND/OR DESIRABLE (SHORT TERM INSTALLATION WITH DESIRE NOT TO
DAMAGE LANDSCAPE) A LESSER TRENCHING DEPTH MAY BE ACCEPTABLE WITH MORE ROBUST
STAKING
6. THE UPHILL SIDE OF THE SEDIMENT CONTROL LOG SHALL BE BACKFILLED WITH SOIL THAT
IS FREE OF ROCKS AND DEBRIS. THE SOIL SHALL BE TIGHTLY COMPACTED INTO THE SHAPE
OF A RIGHT TRIANGLE USING A SHOVEL OR WEIGHTED LAWN ROLLER.
7. FOLLOW MANUFACTURERS' GUIDANCE FOR STAKING. IF MANUFACTURERS' INSTRUCTIONS
DO NOT SPECIFY SPACING, STAKES SHALL BE PLACED ON 4' CENTERS AND EMBEDDED A
MINIMUM OF 6" INTO THE GROUND. 3" OF THE STAKE SHALL PROTRUDE FROM THE TOP OF
THE LOG. STAKES THAT ARE BROKEN PRIOR TO INSTALLATION SHALL BE REPLACED.
SEDIMENT CONTROi I OG MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFIFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE, INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFIECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR DR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. SEDIMENT ACCUMULATED UPSTREAM OF SEDIMENT CONTROL LOG SHALL BE REMOVED AS
NEEDED TO MAINTAIN FUNCTIONALITY OF THE BMP, TYPICALLY WHEN DEPTH OF ACCUMULATED
SEDIMENTS IS APPROXIMATELY ½ OF THE HEIGHT OF THE SEDIMENT CONTROL LOG.
5. SEDIMENT CONTROL LOG SHALL BE REMOVED AT THE END OF CONSTRUCTION. IF
DISTURBED AREAS EXIST AFTER REMOVAL, THEY SHALL BE COVERED WITH TOP SOIL, SEEDED
AND MULCHED OR OTHERWISE STABILIZED IN A MANNER APPROVED BY THE LOCAL
JURISDICTION.
(DETAILS ADAPTED FROM TOWN OF PARKER. COLORADO. JEFF£A$0N COUNTY, COLORADO, DOUGLAS COUNTY, COLORADO,
AND CITY OF AURORA, COLORADO, NOT AVAILIIBLE IN AUTOCAD)
!'IQ.IE;_ MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SCL-5
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Rock Sock (RS) SC-5
Description
A rock sock is constructed of gravel
that has been wrapped by wire mesh or
a geotextile to form an elongated
cylindrical filter. Rock socks are
typically used either as a perimeter
control or as part of inlet protection.
When placed at angles in the curb line,
rock socks are typically referred to as
curb socks. Rock socks are intended to
trap sediment from stormwater runoff
that flows onto roadways as a result of
construction activities.
Appropriate Uses
Rock socks can be used at the perimeter
of a disturbed area to control localized
Photograph RS-1. Rock socks placed at regular intervals in a curb
line can help reduce sediment loading to storm sewer inlets. Rock
socks can also be used as perimeter controls.
sediment loading. A benefit of rock
socks as opposed to other perimeter controls is that they do not have to be trenched or staked into the
ground; therefore, they are often used on roadway construction projects where paved surfaces are present.
Use rock socks in inlet protection applications when the construction of a roadway is substantially
complete and the roadway has been directly connected to a receiving storm system.
Design and Installation
When rock socks are used as perimeter controls, the maximum recommended tributary drainage area per
100 lineal feet ofrock socks is approximately 0.25 acres with disturbed slope length ofup to 150 feet and
a tributary slope gradient no steeper than 3: I. A rock sock design detail and notes are provided in Detail
RS-I. Also see the Inlet Protection Fact Sheet for design and installation guidance when rock socks are
used for inlet protection and in the curb line.
When placed in the gutter adjacent to a curb, rock socks should protrude no more than two feet from the
curb in order for traffic to pass safely. If located in a high traffic area, place construction markers to alert
drivers and street maintenance workers of their presence.
Maintenance and Removal
Rock socks are susceptible to displacement and breaking due to vehicle traffic. Inspect rock socks for
damage and repair or replace as necessary. Remove sediment by sweeping or vacuuming as needed to
maintain the functionality of the BMP, typically when sediment
has accumulated behind the rock sock to one-half of the sock's
height.
Once upstream stabilization is complete, rock socks and
accumulated sediment should be removed and properly disposed.
Rock Sock
iFunctions '. ' : ·'. ---,
Erosion Control
Sediment Control
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
',;
..
No
Yes
No
RS-1
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SC-5 Rock Sock (RS)
RS-2
l½" (MINUS) CRUSHED ROCK
ENCLOSED IN WIRE MESH
WIRE TIE ENDS
l½" (MINUS) CRUSHED ROCK
ENCLOSED IN WIRE MESH
__ _J
l O" ON BEDROCK OR
HARD SURFACE, 2•
IN SOIL
SURFACE L 4" TO 6" MAX AT
CURBS, OTHERWISE
6"-10" DEPENDING
ON EXPECTED
SEDIMENT LOADS
ROCK SOCK SECTION ROCK SOCK PLAN
ROCK SOCK,
TYP
12" 12"
ANY GAP AT JOINT SHALL BE FILLED WITH AN ADEQUATE
AMOUNT OF 1½" (MINUS) CRUSHED ROCK AND WRAPPED
WITH ADDITIONAL WIRE MESH SECURED TO ENDS OF ROCK
REINFORCED SOCK. AS AN ALTERNATIVE TO FILLING JOINTS
BETWEEN ADJOINING ROCK SOCKS WITH CRUSHED ROCK AND
ADDITIONAL WIRE WRAPPING, ROCK SOCKS CAN BE
OVERLAPPED (TYPICALLY 12-INCH OVERLAP) TO AVOID GAPS.
GRADATION TABLE
SIEVE SIZE MASS PERCENT PASSING
SQUARE MESH SIEVES
ROCK SOCK JOINTING NO. 4
2·· 100 1½'' 90 -100
l" 20 -55
¾" 0 -15
¾" 0 -5
ROCK SOCK INSTALi ATION NOTES MATCHES SPECIFICATIONS FOR NO. 4
COARSE AGGREGATE FOR CONCRETE
1. SEE PLAN VIEW FOR: PER MSHTO M4J. ALL ROCK SHALL BE
-LOCATION(S) OF ROCK SOCKS. FRACTURED FACE, ALL SIDES.
2. CRUSHED ROCK SHALL BE l½" (MINUS) IN SIZE WITH A FRACTURED FACE (ALL SIDES)
AND SHALL COMPLY WITH GRADATION SHOWN ON THIS SHEET (1½" MINUS).
J. WIRE MESH SHALL BE FABRICATED OF 10 GAGE POULTRY MESH, OR EQUIVALENT, WITH A
MAXIMUM OPENING OF ½", RECOMMENDED MINIMUM ROLL WIDTH OF 48"
4. WIRE MESH SHALL BE SECURED USING "HOG RINGS" OR WIRE TIES AT 6" CENTERS
ALONG ALL JOINTS AND AT 2" CENTERS ON ENDS OF SOCKS.
5. SOME MUNICIPALITIES MAY ALLOW THE USE OF FILTER FABRIC AS AN ALTERNATIVE TO WIRE
MESH FOR THE ROCK ENCLOSURE.
RS-1. ROCK SOCK PERIMETER CONTROL
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Rock Sock (RS) SC-5
ROCK SOCK MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, ANO PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
J. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. ROCK SOCKS SHALL BE REPLACED IF THEY BECOME HEAVILY SOILED, OR DAMAGED
BEYOND REPAIR.
5. SEDIMENT ACCUMULATED UPSTREAM OF ROCK SOCKS SHALL BE REMOVED AS NEEDED TO
MAINTAIN FUNCTIONALITY OF THE BMP, TYPICALLY WHEN DEPTH OF ACCUMULATED SEDIMENTS
IS APPROXIMATELY ½ OF THE HEIGHT OF THE ROCK SOCK.
6. ROCK SOCKS ARE TO REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AREA IS
STABILIZED AND APPROVED BY THE LOCAL JURISDICTION.
7. WHEN ROCK SOCKS ARE REMOVED, ALL DISTURBED AREAS SHALL BE COVERED WITH
TOPSOIL, SEEDED AND MULCHED OR OTHERWISE STABILIZED AS APPROVED BY LOCAL
JURISDICTION.
(DETAIL ADAPTED fR0M TOWN Of PARKER, COLORADO ANO OTY Of AURORA, COLORADO, NOT AVAILABLE IN NJTOCAO)
t:lQTEc MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
t!OIE; THE DETAILS INCLUDED WITH THIS FACT SHEET SHOW COMMONLY USED, CONVENTIONAL
METHODS OF ROCK SOCK INSTALLATION IN THE DENVER METROPOLITAN AREA. THERE ARE
MANY OTHER SIMILAR PROPRIETARY PRODUCTS ON THE MARKET. UDFCD NEITHER NDORSES
NOR DISCOURAGES USE OF PROPRIETARY PROTECTION PRODUCTS; HOWEVER, IN THE EVENT
PROPRIETARY METHODS ARE USED, THE APPROPRIATE DETAIL FROM THE MANUFACTURER MUST
BE INCLUDED IN THE SWMP AND THE BMP MUST BE INSTALLED AND MAINTAINED AS SHOWN
IN THE MANUFACTURER'S DETAILS.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
RS-3
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Inlet Protection (IP)
Description
Inlet protection consists of permeable
barriers installed around an inlet to
filter runoff and remove sediment prior
to entering a stonn drain inlet. Inlet
protection can be constructed from rock
socks, sediment control logs, silt fence,
block and rock socks, or other materials
approved by the local jurisdiction.
Area inlets can also be protected by
over-excavating around the inlet to
form a sediment trap.
Appropriate Uses
Install protection at storm sewer inlets
that are operable during construction. Photograph IP-1. Inlet protection for a curb opening inlet.
Consider the potential for tracked-out
SC-6
sediment or temporary stockpile areas to contribute sediment to inlets when determining which inlets
must be protected. This may include inlets in the general proximity of the construction area, not limited
to downgradient inlets. Inlet protection is not a stand-alone BMP and should be used in conjunction with
other upgradient BMPs.
Design and Installation
To function effectively, inlet protection measures must be installed to ensure that flows do not bypass the
inlet protection and enter the storm drain without treatment. However, designs must also enable the inlet
to function without completely blocking flows into the inlet in a manner that causes localized flooding.
When selecting the type of inlet protection, consider factors such as type of inlet (e.g., curb or area, sump
or on-grade conditions), traffic, anticipated flows, ability to secure the BMP properly, safety and other
site-specific conditions. For example, block and rock socks will be better suited to a curb and gutter
along a roadway, as opposed to silt fence or sediment control logs, which cannot be properly secured in a
curb and gutter setting, but are effective area inlet protection measures.
Several inlet protection designs are provided in the Design Details. Additionally, a variety of proprietary
products are available for inlet protection that may be approved for use by local governments. If
proprietary products are used, design details and installation procedures from the manufacturer must be
followed. Regardless of the type of inlet protection selected, inlet protection is most effective when
combined with other BMPs such as curb socks and check dams. Inlet protection is often the last barrier
before runoff enters the storm sewer or receiving water.
Design details with notes are provided for these forms of inlet
protection:
IP-I. Block and Rock Sock Inlet Protection for Sump or On-grade
Inlets
IP-2. Curb (Rock) Socks Upstream oflnlet Protection, On-grade
Inlets
Inlet Protection
(various forms)
Functions
Erosion Control
Sediment Control
Site/Material Management
November 20!0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
No
Yes
No
IP-I
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SC-6 Inlet Protection (IP)
IP-3. Rock Sock Inlet Protection for Sump/Area Inlet
IP-4. Silt Fence Inlet Protection for Sump/ Area Inlet
IP-5. Over-excavation Inlet Protection
IP-6. Straw Bale Inlet Protection for Sump/ Area Inlet
CIP-1. Culvert Inlet Protection I
Propriety inlet protection devices should be installed in accordance !with manufacturer specifications.
I
' More information is provided below on selecting inlet protection for sump and on-grade locations.
!
Inlets Located in a Sump
I
When applying inlet protection in sump conditions, it is important that the inlet continue to function
during larger runoff events. For curb inlets, the maximum height of the protective barrier should be lower
than the top of the curb opening to allow overflow into the inlet during larger storms without excessive
localized flooding. If the inlet protection height is greater than the curb elevation, particularly if the filter
becomes clogged with sediment, runoff will not enter the inlet and may bypass it, possibly causing
localized flooding, public safety issues, and downstream erosion and damage from bypassed flows.
Area inlets located in a sump setting can be protected through the use of silt fence, concrete block and
rock socks (on paved surfaces), sediment control logs/straw wattles embedded in the adjacent soil and
stacked around the area inlet (on pervious surfaces), over-excavation around the inlet, and proprietary
products providing equivalent functions.
Inlets Located on a Slope
For curb and gutter inlets on paved sloping streets, block and rock sock inlet protection is recommended
in conjunction with curb socks in the gutter leading to the inlet. For inlets located along unpaved roads,
also see the Check Dam Fact Sheet.
Maintenance and Removal
Inspect inlet protection frequently. Inspection and maintenance guidance includes:
■
■
■
■
IP-2
Inspect for tears that can result in sediment directly entering the inlet, as well as result in the contents
of the BMP (e.g., gravel) washing into the inlet.
Check for improper installation resulting in untreated flows bypassing the BMP and directly entering
the inlet or bypassing to an unprotected downstream inlet. For example, silt fence that has not been
properly trenched around the inlet can result in flows under the silt fence and directly into the inlet.
Look for displaced BMPs that are no longer protecting the inlet. Displacement may occur following
larger storm events that wash away or reposition the inlet protection. Traffic or equipment may also
crush or displace the BMP.
Monitor sediment accumulation upgradient of the inlet protection.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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e
f,,; .
.,_(
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ft
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I
Inlet Protection (IP) SC-6
• Remove sediment accumulation from the area upstream of the inlet protection, as needed to maintain
BMP effectiveness, typically when it reaches no more than half the storage capacity of the inlet
protection. For silt fence, remove sediment when it accumulates to a depth of no more than 6 inches.
Remove sediment accumulation from the area upstream of the inlet protection as needed to maintain
the functionality of the BMP.
• Propriety inlet protection devices should be inspected and maintained in accordance with
manufacturer specifications. If proprietary inlet insert devices are used, sediment should be removed
in a timely manner to prevent devices from breaking and spilling sediment into the storm drain.
Inlet protection must be removed and properly disposed of when the drainage area for the inlet has
reached final stabilization.
November 20 I 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
,,;. ·, -· ,.,-.... · ·ew, -,-,,..,.
IP-3
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SC-6 Inlet Protection (IP)
.--+-----,__ SEE ROCK SOCK DESIGN
DETAIL FOR JOINTING
16" CINDER 16" CINDER
BLOCKS BLOCKS
1' MIN.
FLOW -
2"x4" WOOD STUD
CURB INLET
0
ROCK
SOCKS
-SECTION A -
IP-1. BLOCK AND ROCK SOCK SUMP OR ON GRADE
INLET PROTECTION
Bl OCK ANO CURR SOCK INLET PROTECTION INSTALLATION NOTES
1. SEE ROCK SOCK DESIGN DETAIL FOR INSTALLATION REQUIREMENTS.
2. CONCRETE "CINDER" BLOCKS SHALL BE LAID ON THEIR SIDES AROUND THE INLET IN A
SINGLE ROW. ABUTTING ONE ANOTHER WITH THE OPEN END FACING AWAY FROM THE CURB.
3. GRAVEL BAGS SHALL BE PLACED AROUND CONCRETE BLOCKS, CLOSELY ABUTTING ONE
ANOTHER AND JOINTED TOGETHER IN ACCORDANCE WITH ROCK SOCK DESIGN DETAIL.
r r m
BLOCK AND ROCK SOCK INLET
PROTECTION{SEE DETAIL IP-1)
IP-4
\., \.,
FLOW -
5' MIN 3'-5' TYP.
IP-2. CURB ROCK SOCKS UPSTREAM OF
INLET PROTECTION
CURB ROCK SOCK INLET PROTECTION INSTALLATION NOTES
1. SEE ROCK SOCK DESIGN DETAIL INSTALLATION REQUIREMENTS.
2. PLACEMENT OF THE SOCK SHALL BE APPROXIMATELY 30 DEGREES FROM PERPENDICULAR
IN THE OPPOSITE DIRECTION OF FLOW.
3. SOCKS ARE TO BE FLUSH WITH THE CURB AND SPACED A MINIMUM OF 5 FEET APART.
4. AT LEAST TWO CURB SOCKS IN SERIES ARE REQUIRED UPSTREAM OF ON-GRADE INLETS.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Inlet Protection (IP) SC-6
INLET GRATE 0
ROCK SOCK
SEE ROCK SOCK DETAIL
FOR JOINTING
IP-3. ROCK SOCK SUMP /AREA INLET PROTECTION
ROCK SOCK SUMP/AREA INLET PROTECTION INSTALLATION NOTES
1. SEE ROCK SOCK DESIGN DETAIL FOR INSTALLATION REQUIREMENTS.
2. STIRAW WATTLES/SEDIMENT CONTIROL LOGS MAY BE USED IN PLACE OF ROCK SOCKS FOR
INLETS IN PERVIOUS AREAS. INSTALL PER SEDIMENT CONTROL LOG DETAIL.
INLET GRATE
SILT FENCE (SEE SILT
FENCE DESIGN DETAIL )
IP-4. SILT FENCE FOR SUMP INLET PROTECTION
SILT FENCE INLET PROTECTION INSTALLATION NOTES
1. SEE SILT FENCE DESIGN DETAIL FOR INSTALLATION REQUIREMENTS.
2. POSTS SHALL BE PLACED AT EACH CORNER OF THE INLET AND AROUND THE EDGES
AT A MAXIMUM SPACING OF 3 FEET.
3 .. STIRAW WATTLES/SEDIMENT CONTIROL LOGS MAY BE USED IN PLACE OF SILT FENCE FOR
INLETS IN PERVIOUS AREAS. INSTALL PER SEDIMENT CONTROL LOG DETAIL.
November 20 IO Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
IP-5
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SC-6 Inlet Protection (IP)
IP-6
SHEET
FLOW -,
--------lr-1-~ ~
I i -1 · -I /
L_t-~
SILT
FENCE
AREA
INLET
ECB
£CB
R
OR
OCK FILTER
L CONCENTRAT ED
ROCK SOCK
(USE IF FLOW
IS CONCENTRATED)
FLOW
-
SILT
FENCE
AREA
INLET
0
\,;::"',::::::'.'.1;-;-, MIN
-~-2• MAX
IP-5. OVEREXCAVATION INLET PROTECTION
OVEREXCAVATION INLET PROTECTION INSTALLATION NOTES
1. THIS FORM OF INLET PROTECTION IS PRIMARILY APPLICABLE FOR SITES THAT HAVE NOT
YET REACHED FINAL GRADE AND SHOULD BE USED ONLY FOR INLETS WITH A RELATIVELY
SMALL CONTRIBUTING DRAINAGE AREA.
2. WHEN USING FOR CONCENTRATED FLOWS, SHAPE BASIN IN 2:1 RATIO WITH LENGTH
ORIENTED TOWARDS DIRECTION OF FLOW.
3. SEDIMENT MUST BE PERIODICALLY REMOVED FROM THE OVER EXCAVATED AREA.
STRAW BALE (SEE STRAW
BALE DESIGN DETAIL)
INLET GRATE
IP-6. STRAW BALE FOR SUMP INLET PROTECTION
STRAW BALE BARRIER INLET PROTECTION INSTALLATION NOTES
1. SEE STRAW BALE DESIGN DETNL FOR INSTALLATION REQUIREMENTS.
2. BALES SHALL BE PLACED IN A SINGLE ROW AROUND THE INLET WITH ENDS OF BALES
TIGHTLY ABUTTING ONE ANOTHER.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Inlet Protection (IP) SC-6
GENERAi !NI EI PROTECTION INSTALLATION NOTE$
1. SEE PLAN VIEW FOR:
-LOCATION OF INLET PROTECTION.
-TYPE OF INLET PROTECTION (IP.I. IP.2, IP.3, IP.4, IP.5, IP.6)
2. INLET PROTECTION SHALL BE INSTALLED PROMPTLY AFTER INLET CONSTRUCTION OR PAVING
IS COMPLETE (TYPICALLY WITHIN 48 HOURS). IF A RAJNFALL/RUNOFF EVENT IS FORECAST,
INSTALL INLET PROTECTION PRIOR TO ONSET OF EVENT.
3. MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAJLS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAJL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
INLET PROTECTION MAJNTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAJN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM TIHAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. SEDIMENT ACCUMULATED UPSTREAM OF INLET PROTECTION SHALL BE REMOVED AS
NECESSARY TO MAINTAIN BMP EFFECTIVENESS, TYPICALLY WHEN STORAGE VOLUME REACHES
50% OF CAPACITY, A DEPTH OF 6" WHEN SILT FENCE IS USED, OR ¼ OF THE HEIGHT FOR
STRAW BALES.
5. INLET PROTECTION IS TO REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AREA IS
PERMANENTLY STABILIZED, UNLESS THE LOCAL JURISDICTION APPROVES EARLIER REMOVAL OF
INLET PROTECTION IN STREETS.
6. WHEN INLET PROTECTION AT AREA INLETS IS REMOVED, TIHE DISTURBED AREA SHALL BE
COVERED WITH TOP SOIL, SEEDED AND MULCHED, OR OTIHERWISE STABILIZED IN A MANNER
APPROVED BY THE LOCAL JURISDICTION.
(DETAIL ADAPTED f'ROM TOWN OF P.A.ffi<ER, COLORADO AND CJTY OF AURORA, COLORADO, NOT AVAILABLE IN AUTOCAO)
NQIE; MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
NOTE: THE DETAILS INCLUDED WITH THIS FACT SHEET SHOW COMMONLY USED, CONVENTIONAL
METHODS OF INLET PROTECTION IN THE DENVER METROPOLITAN AREA. THERE ARE MANY
PROPRIETARY INLET PROTECTION METHODS ON THE MARKET. UDFCD NEITIHER ENDORSES NOR
DISCOURAGES USE OF PROPRIETARY INLET PROTECTION; HOWEVER, IN THE EVENT
PROPRIETARY METHODS ARE USED, TIHE APPROPRIATE DETAIL FROM TIHE MANUFACTURER MUST
BE INCLUDED IN TIHE SWMP ANO THE BMP MUST BE INSTALLED AND MAINTAINED AS SHOWN
IN THE MANUFACTURER'S DETAILS.
NQIE; SOME MUNICIPALITIES DISCOURAGE OR PROHIBIT THE USE OF STRAW BALES FOR INLET
PROTECTION. CHECK WITH LOCAL JURISDICTION TO DETERMINE IF STRAW BALE INLET
PROTECTION IS ACCEPTABLE.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
IP-7
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Sediment Basin (SB) SC-7
Description
A sediment basin is a temporary pond
built on a construction site to capture
eroded or disturbed soil transported in
storm runoff prior to discharge from the
site. Sediment basins are designed to
capture site runoff and slowly release it to
allow time for settling of sediment prior
to discharge. Sediment basins are often
constructed in locations that will later be
modified to serve as post-construction
stormwater basins.
Appropriate Uses
Most large construction sites (typically
greater than 2 acres) will require one or
more sediment basins for effective
Photograph SB-1. Sediment basin at the toe of a slope. Photo
courtesy ofWWE.
management of construction site runoff. On linear construction projects, sediment basins may be
impractical; instead, sediment traps or other combinations of BMPs may be more appropriate.
Sediment basins should not be used as stand-alone sediment controls. Erosion and other sediment
controls should also be implemented upstream.
When feasible, the sediment basin should be installed in the same location where a permanent post-
construction detention pond will be located.
Design and Installation
The design procedure for a sediment basin includes these steps:
• Basin Storage Volume: Provide a storage volume of at least 3,600 cubic feet per acre of drainage
area. To the extent practical, undisturbed and/or off-site areas should be diverted around sediment
basins to prevent "clean" runoff from mixing with runoff from disturbed areas. For undisturbed areas
(both on-site and off-site) that cannot be diverted around the sediment basin, provide a minimum of
500 ft 3/acre of storage for undeveloped (but stable) off-site areas in addition to the 3,600 ft 3/acre for
disturbed areas. For stable, developed areas that cannot be diverted around the sediment basin,
storage volume requirements are summarized in Table SB-I.
• Basin Geometry: Design basin with a minimum length-to-width ratio of2:l (L:W). If this cannot be
achieved because of site space constraints, baffling may
be required to extend the effective distance between the
inflow point(s) and the outlet to minimize short-circuiting.
• Dam Embankment: It is recommended that
embankment slopes be 4: I (H:V) or flatter and no steeper
than 3: I (H:V) in any location.
Sediment Basins
Friii'ttions; • ·-
Erosion Control
Sediment Control
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
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No
Yes
No
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SC-7 Sediment Basin (SB)
•
•
Inflow Structure: For concentrated flow entering the basin, provide energy dissipation at the point
of inflow.
Table SB-I. Additional Volume Requirements for Undisturbed and Developed Tributary Areas
Draining through Sediment Basins
Additional Storage Volume (ft')
Imnerviousness (%) Per Acre of Tributarv Area
Undevcloocd 500
IO 800
20 1230
30 1600
40 2030
50 2470
60 2980
70 3560
80 4360
90 5300
100 6460
Outlet Works: The outlet pipe shall extend through the embankment at a minimum slope of0.5
percent. Outlet works can be designed using one of the following approaches:
o Perforated Riser/Plate: Follow the design criteria for Full Spectrum Detention outlets in the
EDB BMP Fact Sheet provided in Chapter 4 of this manual for sizing of outlet perforations with
an emptying time of approximately 72 hours. In lieu of the well-screen trash rack, pack
uniformly sized 1 ½ -to 2-inch gravel in front of the plate. This gravel will need to be cleaned out
frequently during the construction period as sediment accumulates within it. The gravel pack will
need to be removed and disposed of following construction to reclaim the basin for use as a
permanent detention facility. If the basin will be used as a permanent extended detention basin
for the site, a well-screen trash rack will need to be installed once contributing drainage areas
have been stabilized and the gravel pack and accumulated sediment have been removed.
o Floating Skimmer: If a floating skimmer is used, install it using manufacturer's
recommendations. Illustration SB-I provides an illustration of a Faircloth Skimmer Floating
Outlet™, one of the more commonly used floating skimmer outlets. A skimmer should be
designed to release the design volume in no less than 48 hours. The use of a floating skimmer
outlet can increase the sediment capture efficiency of a basin significantly. A floating outlet
continually decants cleanest water off the surface of the pond and releases cleaner water than
would discharge from a perforated riser pipe or plate.
SB-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 IO
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Sediment Basin (SB) SC-7
,
,,
..:1.:~ ·~.-:."1,-... ~
11~i~j•·-~~·,Y .
Illustration SB-I. Outlet strucrure for a temporary sediment basin -Faircloth Skimmer Floating Outlet. Illustration courtesy
of J. W. Faircloth & Sons, Inc., FairclothSkimmer.com.
o Outlet Protection: Outlet protection should be provided where the velocity of flow will exceed
the maximum permissible velocity of the material of the waterway into which discharge occurs.
This may require the use of a riprap apron at the outlet location and/or other measures to keep the
waterway from eroding.
o Emergency Spillway: Provide a stabilized emergency overflow spillway for rainstorms that
exceed the capacity of the sediment basin volume and its outlet. Protect basin embankments from
erosion and overtopping. If the sediment basin will be converted to a permanent detention basin,
design and construct the emergency spillway(s) as required for the permanent facility. If the
sediment basin will not become a permanent detention basin, it may be possible to substitute a
heavy polyvinyl membrane or properly bedded rock cover to line the spillway and downstream
embankment, depending on the height, slope, and width of the embankments.
Maintenance and Removal
Maintenance activities include the following:
• Dredge sediment from the basin, as needed to maintain BMP effectiveness, typically when the design
storage volume is no more than one-third filled with sediment.
• Inspect the sediment basin embankments for stability and seepage.
• Inspect the inlet and outlet of the basin, repair damage, and remove debris. Remove, clean and
replace the gravel around the outlet on a regular basis to remove the accumulated sediment within it
and keep the outlet functioning.
•
•
Be aware that removal of a sediment basin may require dewatering and associated permit
requirements.
Do not remove a sediment basin until the upstream area has been stabilized with vegetation .
November 20 l 0 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SB-3
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SC-7 Sediment Basin (SB)
Final disposition of the sediment basin depends on whether the basin will be converted to a permanent
post-construction stormwater basin or whether the basin area will be returned to grade. For basins being
converted to permanent detention basins, remove accumulated sediment and reconfigure the basin and
outlet to meet the requirements of the final design for the detention facility. If the sediment basin is not to
be used as a permanent detention facility, fill the excavated area with soil and stabilize with vegetation.
SB-4 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
,dir ,...a._,
November 2010
. .,._,,,,,, n+it&ril;MU± ttt -•-
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Sediment Basin (SB)
INLETS TO SEDIMENT BASIN
SHALL ENTER AT FURTHEST
DISTANCE TO OUTLET ANO SHALL
CONSIST OF A TEMPORARY SLOPE
DRAIN
I" TO 2"
CRUSHED ROCK
RIPRAP PAO 7-J--+.--L'(;'..0:'
~}¾,·,'~
4"
TYP.
EL. 01.
HOLE
DIAMETER,
HD
SCHEDULE 40
PVC OR GREATER
;< " L=2 x W MIN. 0
BOTTOM LENGTH ti
'----"O a,
'----4--..()1
'----1--02---1----_.,,
--------l--l1J----1----
...__ __ ,.___04---1,,------
SEDIMENT BASIN PLAN
'EXCEPT WHERE THE HOLES EXCEED 1"
DIAMETER, THEN UP TO TWO COLUMNS
OF SAME SIZED HOLES MAY BE USED
--
RISER PIPE
SC-7
n n·
--4 ---::::::::,_ -_J_,2"
EMBANKMENT
MATERIAL
November 2010
050=9" RIPRAP
TYPE L. (SEE TABLE
MD-7, MAJOR
DRAINAGE, VOL. 1)
RIPRAP BEDDING
SECTION A
CL
CREST LENGTH
EL. 03.00
AT CREST
D50=9" RIPRAP TYPE L
J'
(SEE TABLE MD-7, MAJOR ORAJNAGE. VOL.1)
SECTION B
SB-1. SEDIMENT BASIN
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SB-5
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SC-7
SB-6
Sediment Basin (SB)
TABLE SB-1. SIZING INFORMATION FOR STANDARD SEDIMENT BASIN
Upstream Drainage Basin Bottom Width Spillway Crest Hole
Areo (rounded to Diameter
nearest acre), (oc) (W), (ft) Length (CL), (ft) (HD), (;n)
1 12 ½ 2 %,
2 21 3 '¾6
3 28 5 ½
4 33 ½ 6 ~.
5 38 ½ 8 'JS,
6 43 9 'JS,
7 47 X. 11 'o/i,
8 51 12 '½,
9 55 13 ls
10 58 X. 15 ·~. 11 61 16 '½,
12 64 18 1
13 67 ½ 19 1 X,
14 70 ½ 21 1¼
15 73 X. 22 1 '½e
SEDIMENT BASIN INSTALi ATION NOTES
1. SEE Pl.AN VIEW FOR:
-LOCATION OF SEDIMENT BASIN.
-TYPE OF BASIN (STANDARD BASIN OR NONSTANDARD BASIN).
-FOR STANDARD BASIN, BOTTOM WIDTH W, CREST LENGTH CL, AND HOLE
DIAMETER, HD.
-FOR NONSTANDARD BASIN, SEE CONSTRUCTION DRAWINGS FOR DESIGN OF BASIN
INCLUDING RISER HEIGHT H, NUMBER OF COLUMNS N, HOLE DIAMETER HD AND PIPE
OIAMETER 0.
2. FOR STANDARD BASIN, BOTTOM DIMENSION MAY BE MODIFIED AS LONG AS BOTTOM AREA
IS NOT REDUCED.
3. SEDIMENT BASINS SHALL BE INSTALLED PRIOR TO ANY OTHER LANO-DISTURBING ACTIVITY
THAT RELIES ON ON BASINS AS AS A STORMWATER CONTROL.
4. EMBANKMENT MATERIAL SHALL CONSIST OF SOIL FREE OF DEBRIS, ORGANIC MATERIAL, AND
ROCKS OR CONCRETE GREATER THAN 3 INCHES AND SHALL HAVE A MINIMUM OF 15
PERCENT BY WEIGHT PASSING THE NO. 200 SIEVE.
5. EMBANKMENT MATERIAL SHALL BE COMPACTED TO AT LEAST 95 PERCENT OF MAXIMUM
DENSITY IN ACCORDANCE WITH ASTM D698.
6. PIPE SCH 40 OR GREATER SHALL BE USED.
7. THE DETAILS SHOWN ON THESE SHEETS PERTAIN TO STANDARD SEDIMENT 8ASIN(S)
FOR DRAINAGE AREAS LESS THAN 15 ACRES. SEE CONSTRUCTION DRAWINGS FOR
EMBANKMENT, STORAGE VOLUME, SPILLWAY, OUTLET, AND OUTLET PROTECTION DETAILS FOR
ANY SEDIMENT BASIN(S) THAT HAVE BEEN INDIV!DUALILY DESIGNED FOR DRAINAGE AREAS
LARGER THAN 15 ACRES.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Sediment Basin (SB) SC-7
SEDIMENT BASIN MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM TI-IAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MANTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. SEDIMENT ACCUMULATED IN BASIN SHALL BE REMOVED AS NEEDED TO MAINTAIN BMP
EFFECTIVENESS, TYPICAILLY WHEN SEDIMENT DEPTH REACHES ONE FOOT (I.E., TWO FEET
BELOW THE SPILLWAY CREST).
5. SEDIMENT BASINS ARE TO REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AREA
IS STABILIZED AND GRASS COVER IS ACCEPTED BY Tl-IE LOCAL JURISDICTION.
6. WHEN SEDIMENT BASINS ARE REMOVED, AILL DISTURBED AREAS SHAILL BE COVERED
WITH TOPSOIL, SEEDED AND MULCHED OR OTHERWISE STABILIZED AS APPROVED BY
LOCAIL JURISDICTION.
(OET.AJLS ADAPTED FROM DOUGLAS COUNTY. COLOR.ADO)
~ MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SB-7
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Sediment Trap (ST)
Description
Sediment traps arc fanned by excavating
an area or by placing an earthen
embankment across a low area or
drainage swale. Sediment traps are
designed to capture drainage from
disturbed areas less than one acre and
allow settling of sediment.
Appropriate Uses
Sediment traps can be used in
combination with other layers of erosion
and sediment controls to trap sediment
from small drainage areas (less than one
SC-8
Photograph ST-1. Sediment traps are used to collect sediment-laden
nmofffrom disturbed area. Photo courtesy of EPA Menu ofBMPs.
acre) or areas with localized high sediment loading. For example, sediment traps are often provided in
conjunction with vehicle tracking controls and wheel wash facilities.
Design and Installation
A sediment trap consists of a small excavated basin with an earthen berm and a riprap outlet. The berm
of the sediment trap may be constructed from the excavated material and must be compacted to
95 percent of the maximum density in accordance with ASTM D698. An overflow outlet must be
provided at an elevation at least 6 inches below the top of the berm. See Detail ST-I for additional design
and installation information.
Maintenance and Removal
Inspect the sediment trap embankments for stability and seepage.
Remove accumulated sediment as needed to maintain the effectiveness of the sediment trap, typically
when the sediment depth is approximately one-half the height of the outflow embankment.
Inspect the outlet for debris and damage. Repair damage to the outlet, and remove all obstructions.
A sediment trap should not be removed until the upstream area is sufficiently stabilized. Upon removal of
the trap, the disturbed area should be covered with topsoil and stabilized.
November 20 I 0
Sediment Trap
Functions
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
. .
No
Yes
No
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SC-8
FLOW-·
ST-2
Sediment Trap (ST)
RIPRAP, TYPE M (D50-12") TYP.SMALLER ROCK
SIZE MAY BE ALLOWABLE FOR SMALLER TRAPS
IF APPROVED BY LOCAL JURISDICTION
TOP OF EARTHEN BERM
2:1 MAX.
2:1 MAX.
TRANSITION EXISTING
CHANNEL INTO
SEDIMENT TRAP
2:1 MAX.
2:1 MAX.
w
L
SEDIMENT TRAP PLAN
6" MINIMUM
FREEBOARD
6" (CENTER OF RIPRAP 6"
LOWER THAN ENDS
1'6"
MIN.
12' MIN.
SECTION A
CHANNEL GRADE
JO"
FLOW -
RIPRAP, TYPE M (050-12") TYP.
SMALLER ROCK SIZE MAY BE
ALLOWABLE FOR SMALLER TRAPS IF
APPROVED BY LOCAL JURISDICTION
SECTION B
ST -1. SEDIMENT TRAP
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
0
FLOW -
November 2010
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Sediment Trap (ST) SC-8
SEDIMENT TRAP INSTAI l ATION NOTES
1. SEE PLAN VIEW FOR;
-LOCATION, LENGTH AND WIDTH OF SEDIMENT TRAP.
2. ONLY USE FOR DRANAGE AREAS LESS THAN 1 ACRE.
3. SEDIMENT TRAPS SHALL BE INSTALLED PRIOR TO ANY UPGRADIENT LAND-DISTURBING
ACTIVITIES.
4. SEDIMENT TRAP BERM SHALL BE CONSTRUCTED FROM MATERIAL FROM EXCAVATION, THE
BERM SHALL BE COMPACTED TO 95% OF THE MAXIMUM DENSITY IN ACCORDANCE WITH ASTM
D698.
5. SEDIMENT TRAP OUTLET TO BE CONSTRUCTED OF RIPRAP, TYPE M {DSO= 12") TYP.SMALLER
ROCK SIZE MAY BE ALLOWABLE FOR SMALLER TRAPS IF APPROVED BY LOCAL JURISDICTION,
6. THE TOP OF THE EARTHEN BERM SHALL BE A MINIMUM OF 6" HIGHER THAN THE TOP OF
THE RIPRAP OUTLET STRUCTURE.
7. THE ENDS OF THE RIPRAP OUTLET STRUCTURE SHALL BE A MINIMUM OF 6" HIGHER THAN
THE CENTER OF THE OUTLET STRUCTURE.
SEQIMENT TRAP MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs PS SOON PS
POSSIBLE {AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE,
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEPSURES SHOULD BE
DOCUMENTED THOROUGHLY.
J. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. REMOVE SEDIMENT ACCUMULATED IN TRAP AS NEEDED TO MAINTAIN THE FUNCTIONALITY OF
THE BMP, TYPICALLY WHEN THE SEDIMENT DEPTH REACHES ½ THE HEIGHT OF THE RIPRAP
OUTILET.
5. SEDIMENT TRAPS SHALL REMAIN IN PLACE UNTIL THE UPSTREAM DISTURBED AREA IS
STABILIZED AND APPROVED SY THE LOCAL JURISDICTION.
6. WHEN SEDIMENT TRAPS ARE REMOVED, THE DISTURBED AREA SHALL BE COVERED WITH
TOPSOIL, SEEDED ANO MULCHED OR OTHERWISE STABILIZED IN A MANNER APPROVED BY THE
LOCAL JURISDICTION.
(DETAILS AON>TEO FROM DOUGLAS COUNTY, COLOfW'.)Q, NOT AVAILA81..E IN AUTOCAO)
JfilTL MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UOFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
ST-3
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Vegetated Buffers (VB) SC-9
Description
Buffer strips of preserved natural
vegetation or grass help protect
waterways and wetlands from land
disturbing activities. Vegetated buffers
improve stormwater runoff quality by
straining sediment, promoting
infiltration, and slowing runoff
velocities.
Appropriate Uses
Vegetated buffers can be used to
separate land disturbing activities and
natural surface waters or conveyances.
In many jurisdictions, local governments
Photograph VB-1. A vegetated buffer is maintained between the
area of active construction and the drainage swale. Photo courtesy
ofWWE.
require some type of setback from natural waterways. Concentrated flow should not be directed through
a buffer; instead, runoff should be in the form of sheet flow. Vegetated buffers are typically used in
combination with other perimeter control BMPs such as sediment control logs or silt fence for multi-
layered protection.
Design and Installation
Minimum buffer widths may vary based on local regulations. Clearly delineate the boundary of the
natural buffer area using construction fencing, silt fence, or a comparable technique. In areas that have
been cleared and graded, vegetated buffers such as sod can also be installed to create or restore a
vegetated buffer around the perimeter of the site.
Maintenance and Removal
Inspect buffer areas for signs of erosion such as gullies or rills. Stabilize eroding areas, as needed. If
erosion is due to concentrated flow conditions, it may be necessary to install a level spreader or other
technique to restore sheet flow conditions. Inspect perimeter controls delineating the vegetative buffer
and repair or replace as needed.
Vegetated Buffers
-, __ ·_ .,------,. .. ;;. ·• >> ' ...
November 2010
Functions' ·. . .,; < -· ·, ,t<:"
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
. .. · ___ ,_ :t
Moderate
Yes
Yes
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Chemical Treatment (CT)
Description
Chemical treatment for erosion and
sediment control can take several forms:
I. Applying chemicals to disturbed
surfaces to reduce erosion (these uses
are discussed in the Soil Binders Fact
Sheet).
2. Adding flocculants to sedimentation
ponds or tanks to enhance sediment
removal prior.
SC-10
3. Using proprietary barriers or flow-
through devices containing flocculants
(e.g., "floe logs").
Photograph CT-1. Proprietary chemical treatment system being
used on a construction site with sensitive receiving waters. Photo
courtesy of WWE.
The use of flocculants as described in No. 2 and No. 3 above will likely require special permitting.
Check with the state permitting agency. See the Soil Binder BMP Fact Sheet for information on
surface application of chemical treatments, as described in No. 1.
Appropriate Uses
At sites with fine-grained materials such as clays, chemical addition to sedimentation ponds or tanks can
enhance settling of suspended materials through flocculation.
Prior to selecting and using chemical treatments, it is important to check state and local permit
requirements related to their use.
Design and Installation
Due to variations among proprietary chemical treatment methods, design details are not provided for this
BMP. Chemical feed systems for sedimentation ponds, settling tanks and dewatering bags should be
installed and operated in accordance with manufacturer's recommendations and applicable regulations.
Alum and chitosan are two common chemicals used as flocculants. Because the potential long-term
impact of these chemicals to natural drainageways is not yet fully understood, the state does not currently
allow chemical addition under the CDPS General Stormwater Construction Discharge Permit. Additional
permitting may be necessary, which may include sampling requirements and numeric discharge limits.
Any devices or barriers containing chemicals should be installed following manufacturer's guidelines.
Check for state and local jurisdiction usage restrictions and requirements before including these practices
in the SWMP and implementing them onsite.
November 20 I 0
Chemical Treatment
Functions
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Moderate
Yes
No
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SC-10 Chemical Treatment (CT)
Maintenance and Removal
Chemical feed systems for sedimentation ponds or tanks should be maintained in accordance with
manufacturer's recommendations and removed when the systems are no longer being used. Accumulated
sediment should be dried and disposed of either at a landfill or in accordance with applicable regulations.
Barriers and devices containing chemicals should be removed and replaced when tears or other damage to
the devices are observed. These barriers should be removed and properly disposed of when the site has
been stabilized.
CT-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Construction Phasing/Sequencing (CP)
Description
Effective construction site management
to minimize erosion and sediment
transport includes attention to
construction phasing, scheduling, and
sequencing ofland disturbing activities.
On most construction proj eels, erosion
and sediment controls will need to be
adjusted as the project progresses and
should be documented in the SWMP.
Construction phasing refers to
SM-1
disturbing only part of a site at a time to
limit the potential for erosion from
dormant parts of a site. Grading
activities and construction are completed
and soils are effectively stabilized on one
part of a site before grading and
Photograph CP-1. Construction phasing to avoid disturbing the
entire area at one time. Photo courtesy ofWWE.
construction begins on another portion of the site.
Construction sequencing or scheduling refers to a specified work schedule that coordinates the timing of
land disturbing activities and the installation of erosion and sediment control practices.
Appropriate Uses
All construction projects can benefit from upfront planning to phase and sequence construction activities
to minimize the extent and duration of disturbance. Larger projects and linear construction projects may
benefit most from construction sequencing or phasing, but even small projects can benefit from
construction sequencing that minimizes the duration of disturbance.
Typically, erosion and sediment controls needed at a site will change as a site progresses through the
major phases of construction. Erosion and sediment control practices corresponding to each phase of
construction must be documented in the SWMP.
Design and Installation
BMPs appropriate to the major phases of development should be identified on construction drawings. In
some cases, it will be necessary to provide several drawings showing construction-phase BMPs placed
according to stages of development (e.g., clearing and grading, utility installation, active construction,
final stabilization). Some municipalities in the Denver area set maximum sizes for disturbed area
associated with phases of a construction project. Additionally, requirements for phased construction
drawings vary among local governments within the UDFCD boundary. Some local governments require
separate erosion and sediment control drawings for initial
BMPs, interim conditions (in active construction), and final
Construction Scheduling
stabilization.
November 2010
"11unaio"ns,. .·· ... · .. _._·.
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
" ,, .
Moderate
Moderate
Yes
CP-1
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SM-1 Construction Phasing/Sequencing (CP)
Typical construction phasing BMPs include:
•
•
Limit the amount of disturbed area at any given time on a site to the extent practical. For example, a
l00-acre subdivision might be constructed in five phases of20 acres each.
If there is carryover of stockpiled material from one phase to the next, position carryover material in a
location easily accessible for the pending phase that will not require disturbance of stabilized areas to
access the stockpile. Particularly with regard to efforts to balance cut and fill at a site, careful
planning for location of stockpiles is important.
Typical construction sequencing BMPs include:
• Sequence construction activities to minimize duration of soil disturbance and exposure. For example,
when multiple utilities will occupy the same trench, schedule installation so that the trench does not
have to be closed and opened multiple times.
• Schedule site stabilization activities (e.g., landscaping, seeding and mulching, installation of erosion
control blankets) as soon as feasible following grading.
• Install initial erosion and sediment control practices before construction begins. Promptly install
additional BMPs for inlet protection, stabilization, etc., as construction activities are completed.
Table CP-1 provides typical sequencing of construction activities and associated BMPs.
Maintenance and Removal
When the construction schedule is altered, erosion and sediment control measures in the SWMP and
construction drawings should be appropriately adjusted to reflect actual "on the ground" conditions at the
construction site. Be aware that changes in construction schedules can have significant implications for
site stabilization, particularly with regard to establishment of vegetative cover.
CP-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Construction Phasing/Sequencing (CP) SM-1
Table CP-1. Typical Phased BMP Installation for Construction Projects
Project
Phase
Pre-
disturbance,
Site Access
Site Clearing
•
•
•
BMPs
Install sediment controls downgradient of access point ( on paved streets this may consist
of inlet protection).
Establish vehicle tracking control at entrances to paved streets. Fence as needed .
Use construction fencing to define the boundaries of the project and limit access to areas of
the site that are not to be disturbed.
Note: it may be necessary to protect inlets in the general vicinity of the site, even if not
downgradient, if there is a possibility that sediment tracked from the site could contribute
to the inlets.
•
•
•
Install perimeter controls as needed on downgradient perimeter of site (silt fence, wattles,
etc).
Limit disturbance to those areas planned for disturbance and protect undisturbed areas
within the site (construction fence, flagging, etc).
Preserve vegetative buffer at site perimeter .
Create stabilized staging area.
■ Locate portable toilets on flat surfaces away from drainage paths. Stake in areas
susceptible to high winds.
• Construct concrete washout area and provide signage.
Establish waste disposal areas.
and Grubbing • Install sediment basins.
•
•
•
November 2010
Create dirt perimeter berms and/or brush barriers during grubbing and clearing .
Separate and stockpile topsoil, leave roughened and/or cover.
Protect stockpiles with perimeter control BMPs. Stockpiles should be located away from
drainage paths and should be accessed from the upgradient side so that perimeter controls
can remain in place on the downgradient side. Use erosion control blankets, temporary
seeding, and/or mulch for stockpiles that will be inactive for an extended period.
Leave disturbed area of site in a roughened condition to limit erosion. Consider temporary
revegetation for areas of the site that have been disturbed but that will be inactive for an
extended period.
Water to minimize dust but not to the point that watering creates runoff.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
CP-3
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SM-1
Project
Phase
Utility And
Infrastructure
Installation
Building
Construction
Final Grading
Final
Stabilization
CP-4
Construction Phasing/Sequencing (CP)
BMPs
In Addition to the Above BMPs:
• Close trench as soon as possible (generally at the end of the day) .
• Use rough-cut street control or apply road base for streets that will not be promptly paved .
• Provide inlet protection as streets are paved and inlets are constructed .
• Protect and repair BMPs, as necessary .
• Perform street sweeping as needed .
In Addition to the Above BMPs:
• Implement materials management and good housekeeping practices for home building
activities.
• Use perimeter controls for temporary stockpiles from foundation excavations .
• For lots adjacent to streets, lot-line perimeter controls may be necessary at the back of
curb.
In Addition to the Above BMPs:
• Remove excess or waste materials .
• Remove stored materials .
In Addition to the Above BMPs:
•
•
•
Seed and mulch/tackify .
Seed and install blankets on steep slopes .
Remove all temporary BMPs when site has reached final stabilization.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Protection of Existing Vegetation (PV) SM-2
Description
Protection of existing vegetation on a
construction site can be accomplished
through installation of a construction
fence around the area requiring protection.
In cases where upgradient areas are
disturbed, it may also be necessary to
install perimeter controls to minimize
sediment loading to sensitive areas such as
wetlands. Existing vegetation may be
designated for protection to maintain a
stable surface cover as part of construction
phasing, or vegetation may be protected in
areas designated to remain in natural
condition under post-development
conditions (e.g., wetlands, mature trees,
riparian areas, open space). Photograph PV-1. Protection of existing vegetation and a sensitive
area. Photo courtesy ofCDOT.
Appropriate Uses
Existing vegetation should be preserved for the maximum practical duration on a construction site
through the use of effective construction phasing. Preserving vegetation helps to minimize erosion and
can reduce revegetation costs following construction.
Protection of wetland areas is required under the Clean Water Act, unless a permit has been obtained from
the U.S. Army· Corps of Engineers (USACE) allowing impacts in limited areas.
If trees are to be protected as part of post-development landscaping, care must be taken to avoid several
types of damage, some of which may not be apparent at the time of injury. Potential sources of injury
include soil compaction during grading or due to construction traffic, direct equipment-related injury such
as bark removal, branch breakage, surface grading and trenching, and soil cut and fill. In order to
minimize injuries that may lead to immediate or later death of the tree, tree protection zones should be
developed during site design, implemented at the beginning of a construction project, as well as continued
during active construction.
Design and Installation
General
Once an area has been designated as a preservation area, there should be no construction activity allowed
within a set distance of the area. Clearly mark the area with construction fencing. Do not allow
stockpiles, equipment, trailers or parking within the
protected area. Guidelines to protect various types of
existing vegetation follow. Protection of Existing Vegetation
November 2010
Funi'tions .-•··:. '-• ;_: .. ..
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
"' . . _y,.,;: ,,.'"'.>
Yes
Moderate
Yes
PV-1
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SM-2 Protection of Existing Vegetation (PV)
Surface Cover During Phased Construction
Install construction fencing or other perimeter controls around areas to be protected from clearing and
grading as part of construction phasing.
Maintaining surface cover on steep slopes for the maximum practical duration during construction is
recommended.
Open Space Preservation
Where natural open space areas will be preserved as part of a development, it is important to install
construction fencing around these areas to protect them from compaction. This is particularly important
when areas with soils with high infiltration rates are preserved as part of LID designs. Preserved open
space areas should not be used for staging and equipment storage.
Wetlands and Riparian Areas
Install a construction fence around the perimeter of the wetland or riparian (streamside vegetation) area to
prevent access by equipment. In areas downgradient of disturbed areas, install a perimeter control such as
silt fence, sediment control logs, or similar measure to minimize sediment loading to the wetland.
Tree Protection 1
• Before beginning construction operations, establish a tree protection zone around trees to be
preserved by installing construction fences. Allow enough space from the trunk to protect the root
zone from soil compaction and mechanical damage, and the branches from mechanical damage (see
Table PV-1). !flow branches will be kept, place the fence outside of the drip line. Where this is not
possible, place fencing as far away from the trunk as possible. In order to maintain a healthy tree, be
aware that about 60 percent of the tree's root zone extends beyond the drip line.
Table PV-1
Guidelines for Determining the Tree Protection Zone
(Source: Matheny and Clark, 1998; as cited in GreenCO and WWE 2008)
Distance from Trunk (ft) per inch of DBH
Species Tolerance to Damage Young Mature Over mature
Good 0.5' 0.75' 1.0'
Moderate 0.75' 1.0' 1.25'
Poor 1.0' 1.25' 1.5'
Notes: DBH = diameter at breast height (4.5 ft above grade); Young= <20% of
life expectancy; Mature = 20%-80% of life expectancy; Over mature =>80% of
life expectancy
• Most tree roots grow within the top 12 to 18 inches of soil. Grade changes within the tree protection
zone should be avoided where possible because seemingly minor grade changes can either smother
1 Tree Protection guidelines adapted from GreenCO and WWE (2008). Green Industry Best Management Practices (BMPs) for
the Conservation and Protection of Water Resources in Colorado: Moving Toward Sustainability, Third Release. See
\\'ww.grcenco.org for more detailed guidance on tree preservation.
PV-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Protection of Existing Vegetation (PV) SM-2
•
•
•
roots (in fill situations) or damage roots (in cut situations). Consider small walls where needed to
avoid grade changes in the tree protection zone.
Place and maintain a layer of mulch 4 to 6-inch thick from the tree trunk to the fencing, keeping a
6-inch space between the mulch and the trunk. Mulch helps to preserve moisture and decrease soil
compaction if construction traffic is unavoidable. When planting operations are completed, the mulch
may be reused throughout planting areas.
Limit access, if needed at all, and appoint one route as the main entrance and exit to the tree
protection zone. Within the tree protection zone, do not allow any equipment to be stored, chemicals
to be dumped, or construction activities to take place except fine grading, irrigation system
installation, and planting operations. These activities should be conducted in consultation with a
landscaping professional, following Green Industry BMPs.
Be aware that soil compaction can cause extreme damage to tree health that may appear gradually
over a period of years. Soil compaction is easier to prevent than repair.
Maintenance and Removal
Repair or replace damaged or displaced fencing or other protective barriers around the vegetated area.
If damage occurs to a tree, consult an arborist for guidance on how to care for the tree. If a tree in a
designated preservation area is damaged beyond repair, remove and replace with a 2-inch diameter tree of
the same or similar species.
Construction equipment must not enter a wetland area, except as permitted by the U.S. Army Corps of
Engineers (USA CE). Inadvertent placement of fill in a wetland is a 404 permit violation and will require
notification of the USACE.
If damage to vegetation occurs in a protected area, reseed the area with the same or similar species,
following the recommendations in the USDCM Revegetation chapter.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
PV-3
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Construction Fence (CF)
Description
A construction fence restricts site access
to designated entrances and exits,
delineates construction site boundaries,
and keeps construction out of sensitive
areas such as natural areas to be
preserved as open space, wetlands and
npanan areas.
Appropriate Uses
SM-3
A construction fence can be used to
delineate the site perimeter and locations
within the site where access is restricted
to protect natural resources such as
wetlands, waterbodies, trees, and other
natural areas of the site that should not be
disturbed.
Photograph CF-1. A construction fence helps delineate areas where
existing vegetation is being protected. Photo courtesy of Douglas
County.
If natural resource protection is an objective, then the construction fencing should be used in combination
with other perimeter control BMPs such as silt fence, sediment control logs or similar measures.
Design and Installation
Construction fencing may be chain link or plastic mesh and should be installed following manufacturer's
recommendations. See Detail CF-I for typical installations.
Do not place construction fencing in areas within work limits of machinery.
Maintenance and Removal
•
•
•
Inspect fences for damage; repair or replace as necessary .
Fencing should be tight and any areas with slumping or fallen posts should be reinstalled .
Fencing should be removed once construction is complete .
Construction Fence
. .
. Functions. ' . ·.
Erosion Control
Sediment Control
Site/Material Management
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
·. .
No
No
Yes
CF-I
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SM-3
CF-2
Construction Fence (CF)
PLASTIC CAP, TYP.
STUDDED STEEL
TEE POST
ORANGE RESINET /"'"
5' M IN. CONSTRUCTION FENCE
OR APPROVED EQUAL ,,,,,,~c.. I--1-)
EXISTING r--r r GRADE
~-
/
->-~ --/,,
\
1'
~rn ,~
/ ,,,,..-,_
MIN. / /
/
"'::.i-V 1)1
SPACING ,,.,
,,,,c:.c-
I -17"' ,,,
...(' ,--_,_,_
~ ~ /
I
I [;7 STUDDED STEEL
I TEE PDST
4' M IN.
I -:;!,.,-' I
I I
I /
< -,l,-,,,
~
CF-1. PLASTIC MESH CONSTRUCTION FENCE
CONSTRUCTION FENCE INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATION OF CONSTRUCTION FENCE.
2. CONSTRUCTION FENCE SHOWN SHALL SE INSTALLED PRIOR TO ANY LAND DISTURBING
ACTIVITIES.
I\
3. CONSTRUCTION FENCE SHALL SE COMPOSED OF ORANGE. CONTRACTOR-GRADE MATERIAL
THAT IS AT LEAST 4' HIGH. METAL POSTS SHOULD HAVE A PLASTIC CAP FOR SAFETY.
4. STUDDED STEEL TEE POSTS SHALL SE UTILIZED TO SUPPORT THE CONSTRUCTION FENCE.
MAXIMUM SPACING FOR STEEL TEE POSTS SHALL BE 1 o'.
5. CONSTRUCTION FENCE SHALL BE SECURELY FASTENED TO THE TOP, MIDDLE, AND
BOTTOM OF EACH POST.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Construction Fence (CF) SM-3
CONS TR\ ICIION FENCE MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, .NOT REACTIVE. INSPECT BMPs />S SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECflVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. CONSTRUCTION FENCE SHALL BE REPAIRED OR REPLACED WHEN THERE ARE SIGNS OF
DAMAGE SUCH />S RIPS OR SAGS. CONSTRUCTION FENCE IS TO REMAIN IN PLACE UNTIL THE
UPSTREAM DISTURBED AREA IS STABILIZED AND APPROVED BY THE LOCAL JURISDICTION.
5. WHEN CONSTRUCTION FENCES ARE REMOVED, All DISTURBED ARE/>S ASSOCIATED WITH THE
INSTALLATION, MAINTENANCE, AND/OR REMOVAL OF THE FENCE SHALL BE COVERED WITH
TOPSOIL, SEEDED AND MULCHED, OR OTHERWISE STABILIZED />S APPROVED BY LOCAL
JURISDICTION.
!iQJJ;;. MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
(DETAIL ADAPTED FROM TOWN OF PARKER. COLORADO. NOT AVAll.o'SlE IN AUTOCAD)
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
CF-3
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Vehicle Tracking Control (VTC)
Description
Vehicle tracking controls provide
stabilized construction site access where
vehicles exit the site onto paved public
roads. An effective vehicle tracking
control helps remove sediment (mud or
dirt) from vehicles, reducing tracking onto
the paved surface.
Appropriate Uses
SM-4
Implement a stabilized construction
entrance or vehicle tracking control where
frequent heavy vehicle traffic exits the
construction site onto a paved roadway. An
effective vehicle tracking control is
Photograph VTC-1. A vehicle tracking control pad constructed with
properly sized rock reduces off-site sediment tracking.
particularly important during the following conditions:
• Wet weather periods when mud is easily tracked off site.
• During dry weather periods where dust is a concern.
• When poorly drained, clayey soils are present on site.
Although wheel washes are not required in designs of vehicle tracking controls, they may be needed at
particularly muddy sites.
Design and Installation
Construct the vehicle tracking control on a level surface. Where feasible, grade the tracking control
towards the construction site to reduce off-site runoff. Place signage, as needed, to direct construction
vehicles to the designated exit through the vehicle tracking control. There are several different types of
stabilized construction entrances including:
VTC-1. Aggregate Vehicle Tracking Control. This is a coarse-aggregate surfaced pad underlain by a
geotextile. This is the most common vehicle tracking control, and when properly maintained can be
effective at removing sediment from vehicle tires.
VTC-2. Vehicle Tracking Control with Construction Mat or Turf Reinforcement Mat. This type of
control may be appropriate for site access at very small construction sites with low traffic volume over
vegetated areas. Although this application does not typically remove sediment from vehicles, it helps
protect existing vegetation and provides a stabilized entrance.
Vehicle Tracking Control
November 2010
Functions
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Moderate
Yes
Yes
VTC-1
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SM-4 Vehicle Tracking Control (VTC)
VTC-3. Stabilized Construction Entrance/Exit with Wheel Wash. This is an aggregate pad, similar
to VTC-1, but includes equipment for tire washing. The wheel wash equipment may be as simple as
hand-held power washing equipment to more advance proprietary systems. When a wheel wash is
provided, it is important to direct wash water to a sediment trap prior to discharge from the site.
Vehicle tracking controls arc sometimes installed in combination with a sediment trap to treat runoff.
Maintenance and Removal
Inspect the area for degradation and
replace aggregate or material used for a
stabilized entrance/exit as needed. If the
area becomes clogged and ponds water,
remove and dispose of excess sediment
or replace material with a fresh layer of
aggregate as necessary.
With aggregate vehicle tracking controls,
ensure rock and debris from this area do
not enter the public right-of-way.
Remove sediment that is tracked onto the
public right of way daily or more
frequently as needed. Excess sediment
in the roadway indicates that the
stabilized construction entrance needs
maintenance.
Ensure that drainage ditches at the
entrance/exit area remain clear.
Photograph VTC-2. A vehicle tracking control pad with wheel wash
facility. Photo courtesy of Torn Gore.
A stabilized entrance should be removed only when there is no longer the potential for vehicle tracking to
occur. This is typically after the site has been stabilized.
When wheel wash equipment is used, be sure that the wash water is discharged to a sediment trap prior to
discharge. Also inspect channels conveying the water from the wash area to the sediment trap and
stabilize areas that may be eroding.
When a construction entrance/exit is removed, excess sediment from the aggregate should be removed
and disposed of appropriately. The entrance should be promptly stabilized with a permanent surface
following removal, typically by paving.
VTC-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 I 0
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Vehicle Tracking Control (VTC} SM-4
SIDEWALK OR OTHER
PAVED SURFACE
INSTALL ROCK FLUSH WITH
OR BELOW TOP OF PAVEMENT
COMPACTED SUBGRADE
20 FOOT
(WIDTH CAN BE
LESS IF CONST.
VEHICLES ARE
PHYSICALLY
CONFINED ON
BOTH SIDES)
UNLESS OTHERWISE SPECIFIED
BY LOCAL JURISDICTION, USE
COOT SECT. #703, MSHTO #3
COARSE AGGREGATE OR 6"
MINUS ROCK
NON-WOVEN GEOTEXTILE FABRIC
BETWEEN SOIL ANO ROCK
UNLESS OTHERWISE SPECIFIED BY LOCAL
JURISDICTION, USE COOT SECT. #703, MSHTO
#3 COARSE AGGREGATE
OR 6" MINUS ROCK i g" (MIN.)
SECTION A
T
NON-WOVEN GEOTEXTILE
FABRIC
VTC-1. AGGREGATE VEHICLE TRACKING CONTROL
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
VTC-3
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SM-4 Vehicle Tracking Control (VTC)
VTC-4
PUBLIC
ROADWAY
NOTE: WASH WATER
MAY NOT CONTAIN
CHEMICALS OR SOAPS
WITHOUT OBTAINING
A SEPARATE PERMIT WASH RACK
6'7" MIN.
DITCH TO CARRY
WASH WATER TO
SEDIMENT TRAP
OR BASIN
~~I~ REINFORCED CON~ . . • . . -,,; '. , . t'1 "P'.
(MAY SUBSTITUTE STEEL CA:E~PACE
GUARD FOR CONCRETE RACK)
SECTION A
VTC-2. AGGREGATE VEHICLE TRACKING CONTROL WITH
WASH RACK
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Vehicle Tracking Control (VTC) SM-4
DISTURBED AREA,
CONSTRUCTION SITE,
STABILIZED STORAGE AREA
OR STAGING AREA
EXISTING 1 2 • Ml N
PAVED
ROADWAY
'
>-~ I
0
<(
0 er:
0 w t
C) z
i5i x w
.
CONSTRUCTION MATS, WOVEN OR TRM
50' MIN
STAKES
~
,J, ~
~· .-p " ,"° ~.,. . ~
SPIKES OR~
'l,o o" r:Y x:-~ "~ ~ ' dv ,;,<, .:,.'-o ,._o
d"(:;,'<'"" q'<' ,,. 1'<, ,., ...
e,O t,",.'<,~
o_, ~o
' , ~~
CONSTRUCTION MATS, WOVEN
OR TURF REINFORCEMENT STRAP
TRM END OVERLAP WITH
SPIKES OR STAKES
MAT (TRM) CONNECTORS ~~ : :,=,
CONSTRUCTION MAT END
VERLAP INTERLOCK WITH
c=
RESTRICT CONST. VEHICLE 0
ACCESS TO SIDES OF MAT
"
STRAP CONNECTORS
20'
t
OR AS REQUIRED
TO ACCOMMODATE
ANTICIPATED
TRAFFlC {WIDTH
CAN BE LESS IF
CONST. VEHICLES
ARE PHYSICALLY
CONFINED ON BOTH
SIDES)
VTC-3. VEHICLE TRACKING CONTROL W / CONSTRUCTION
MAT OR TURF REINFORCEMENT MAT (TRM)
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
VTC-5
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SM-4
VTC-6
Vehicle Tracking Control (VTC)
STABILIZED CONSTRUCTION ENTRANCE/EXIT INSTALLATION NOTES
1. SEE PLAN VIEW FOR
-LOCATION OF CONSTRUCTION ENTRANCE(S)/EXIT(S).
-TYPE OF CONSTRUCTION ENTRANCE(S)/EXITS(S) (WITH/WITHOUT WHEEL WASH,
CONSTRUCTION MAT OR TRM).
2. CONSTRUCTION MAT OR TRM STABILIZED CONSTRUCTION ENTRANCES ARE ONLY TO BE
USED ON SHORT DURATION PROJECTS (TYPICALLY RANGING FROM A WEEK TO A MONTH)
WHERE THERE WILIL BE LIMITED VEHICULAR ACCESS.
3. A STABILIZED CONSTRUCTION ENTRANCE/EXIT SHALL BE LOCATED AT ALIL ACCESS POINTS
WHERE VEHICLES ACCESS THE CONSTRUCTION SITE FROM PAVED RIGHT-OF-WAYS.
4. STABILIZED CONSTRUCTION ENTRANCE/EXIT SHALL BE INSTALLED PRIOR TO ANY LAND
DISTURBING ACTIVITIES.
5. A NON-WOVEN GEOTEXTILE FABRIC SHALL BE PLACED UNDER THE STABILIZED
CONSTRUCTION ENTRANCE/EXIT PRIOR TO THE PLACEMENT OF ROCK.
6. UNLESS OTHERWISE SPECIFIED BY LOCAL JURISDICTION, ROCK SHALL CONSIST OF DOT
SECT. #703, MSHTO #3 COARSE AGGREGATE OR 6" {MINUS) ROCK.
STABILIZED CONSTRUCTION ENTRANCE/EXIT MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, ANO PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS ANO MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAJLURE.
4. ROCK SHALIL BE REAPPLIED OR REGRADED AS NECESSARY TO THE STABILIZED
ENTRANCE/EXIT TO MAJNTAIN A CONSISTENT DEPTH.
5. SEDIMENT TRACKED ONTO PAVED ROADS IS TO BE REMOVED THROUGHOUT THE DAY ANO
AT THE END OF THE DAY BY SHOVELING OR SWEEPING. SEDIMENT MAY NOT BE WASHED
DOWN STORM SEWER DRAINS.
tiQTE; MANY JURISDICTIONS HAVE BMP DETAJLS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
(DET.-JLS ADAPrED FROM CITY or BROOMFIELD, COLORADO. NOT AV~LABLE IN AUTOCAD)
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 IO
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Stabilized Construction Roadway (SCR)
A stabilized construction roadway is a
temporary method to control sediment
runoff, vehicle tracking, and dust from
roads during construction activities.
Appropriate Uses
Use on high traffic construction roads to
minimize dust and erosion.
Stabilized construction roadways are
used instead of rough-cut street controls
on roadways with frequent construction
traffic.
Design and Installation
Photograph SCR-1. Stabilized construction roadway.
SM-5
Stabilized construction roadways typically involve two key components: 1) stabilizing the road surface
with an aggregate base course of 3-inch-diameter granular material and 2) stabilizing roadside ditches, if
applicable. Early application of road base is generally suitable where a layer of coarse aggregate is
specified for final road construction.
Maintenance and Removal
Apply additional gravel as necessary to ensure roadway integrity.
Inspect drainage ditches along the roadway for erosion and stabilize, as needed, through the use of check
dams or rolled erosion control products.
Gravel may be removed once the road is ready to be paved. Prior to paving, the road should be inspected
for grade changes and damage. Regrade and repair as necessary.
November 20 I 0
Stabilized Construction Roadway
Functions
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Yes
Moderate
Yes
SCR-1
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Stabilized Staging Area (SSA) SM-6
Description
A stabilized staging area is a clearly
designated area where construction
equipment and vehicles, stockpiles, waste
bins, and other construction-related
materials are stored. The contractor
office trailer may also be located in this
area. Depending on the size of the
construction site, more than one staging
area may be necessary.
Appropriate Uses
Most construction sites will require a
staging area, which should be clearly
designated in SWMP drawings. The layout
of the staging area may vary depending on
Photograph SSA-I. Example of a staging area with a gravel surface to
prevent mud tracking and reduce runoff. Photo courtesy of Douglas
County.
the type of construction activity. Staging areas located in roadways due to space constraints require
special measures to avoid materials being washed into storm inlets.
Design-and Installation
Stabilized staging areas should be completed prior to other construction activities beginning on the site.
Major components of a stabilized staging area include:
■
■
■
■
•
•
Appropriate space to contain storage and provide for loading/unloading operations, as well as parking
if necessary.
A stabilized surface, either paved or covered, with 3-inch diameter aggregate or larger.
Perimeter controls such as silt fence, sediment control logs, or other measures.
Construction fencing to prevent unauthorized access to construction materials.
Provisions for Good Housekeeping practices related to materials storage and disposal, as described in
the Good Housekeeping BMP Fact Sheet.
A stabilized construction entrance/exit, as described in the Vehicle Tracking Control BMP Fact Sheet,
to accommodate traffic associated with material delivery and waste disposal vehicles.
Over-sizing the stabilized staging area may result in disturbance of existing vegetation in excess of that
required for the project. This increases costs, as well as
requirements for long-term stabilization following the
construction period. When designing the stabilized staging area,
minimize the area of disturbance to the extent practical.
Stabilized Staging Arca
November 2010
..
Functions
Erosion Control
Sediment Control
Site/Material
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
Yes
Moderate
Yes
SSA-1
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SM-6 Stabilized Staging Area (SSA)
Minimizing Long-Term Stabilization Reqnirements .
r: ~i II&ti_li_ze_6f(,si(e•.R~rking·a11d -~estrict v_efocl_~ •. act esl!tt'the ·•site:
'.\ ~):;;-:'.;i•t::~ti}trr J?ft:\: c:t:: . . __ -( -_ ,, . --, -.-'-,:_-t~ --~--:,.::\:_"-~_--;::f--?:.n1\{:11s/i1r&::_:_ //i _ . , _ . -. _
. .. . . . • . . . . . · . . .. . .. .. rovided in.an area thatwill not be disturbed·
~:✓ ·-. . . . .•
See Detail SSA-I for a typical stabilized staging area and SSA-2 for a stabilized staging area when
materials staging in roadways is required.
Maintenance and Removal
Maintenance of stabilized staging areas includes maintaining a stable surface cover of gravel, repairing
perimeter controls, and following good housekeeping practices.
When construction is complete, debris, unused stockpiles and materials should be recycled or properly
disposed. In some cases, this will require disposal of contaminated soil from equipment leaks in an
appropriate landfill. Staging areas should then be permanently stabilized with vegetation or other surface
cover planned for the development.
SSA-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Stabilized Staging Area (SSA)
.
CONSTRUCTION \ l ..
SITE ACCESS ~ \ i
\ \f
STABILIZED I
CONSTRUCTION
ENTRANCE (SEE
DETAILS VTC-1
TO VTC-3)
. .
. :ONStTE •
CONSTRUCtlON
VEHIC(.E .
P'ARKING (1F•
. .
NEEDEq),,
• • "'ATERiAL •.
STb'RAGE
AREA ~
EXISTING ROADWAY
3" MIN. THICKNESS
GRANULAR MATERIAL
SSA-1. STABILIZED STAGING AREA
STABILIZED STAGING AREA INSTALLATION NOTES
1. SEE PLAN VIEW FOR
-LOCATION OF STAGING .. AREA{S).
-CONTRACTOR MAY ADJUST LOCATION AND SIZE OF STAGING AREA WITH APPROVAL
FROM THE LOCAL JURISDICTION.
2. STABILIZED STAGING AREA SHOULD BE APPROPRIATE FOR THE NEEDS OF THE SITE.
OVERSIZING RESULTS IN A LARGER AREA TO STABILIZE FOLLOWING CONSTRUCTION.
3. STAGING AREA SHALL BE STABILIZED PRIOR TO OTHER OPERATIONS ON THE SITE.
4. THE STABILIZED STAGING AREA SHALL CONSIST OF A MINIMUM 3" THICK GRANULAR
MATERIAL.
5. UNLESS OTHERWISE SPECIFIED BY LOCAL JURISDICTION, ROCK SHALL CONSIST OF DOT
SECT. #703, MSHTO #3 COARSE AGGREGATE OR 6" {MINUS) ROCK.
6. ADDITIONAL PERIMETER BMPs MAY BE REQUIRED INCLUDING BUT NOT LIMITED TO SILT
FENCE AND CONSTRUCTION FENCING.
STABILIZED STAGING AREA MAINTENANCE NOTES
SM-6
1. INSPECT BMPs EACH WORKDAY, AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs AS SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE MEASURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED. REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. ROCK SHALL BE REAPPLIED OR REGRADED AS NECESSAIRY IF RUTTING OCCURS OR
UNDERLYING SUBGRAIDE BECOMES EXPOSED.
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
SSA-3
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SM-6
SSA-4
Stabilized Staging Area (SSA)
SfABILIZED STAGING AREA MAINTENANCE NOTES
5. STABILIZED STAGING AREA SHALL BE ENLARGED IF NECESSARY TO CONTAIN PARKING,
STORAGE, AND UNLOADING/LOADING OPERATIONS.
6. THE STABILIZED STAGING AREA SHALL BE REMOVED AT THE END OF CONSTRUCTION. THE
GRANULAR MATERIAL SHALL BE REMOVED OR, IF APPROVED BY THE LOCAL JURISDICTION,
USED ON SITE, AND THE AREA COVERED WITH TOPSOIL, SEEDED AND MULCHED OR
OTHERWISE STABILIZED IN A MANNER APPROVED BY LOCAL JURISDICTION.
llil.IE;_ MANY MUNICIPALITIES PROHIBIT THE USE OF RECYCLED CONCRETE AS GRANULAR
MATERIAL FOR STABILIZED STAGING AREAS DUE TO DIFFICULTIES WITH RE-ESTABLISHMENT OF
VEGETATION IN AREAS WHERE RECYCLED CONCRETE WAS PLACED.
llil.IE;_ MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCD STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
(DETAILS ADAPTED FROM DOUGLAS COUNTY, COL()R.A.00, NOT AV.An.ABLE IN AUTOCAO)
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 20 IO
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Street Sweeping and Vacuuming (SS) SM-7
Description
Street sweeping and vacuuming remove
sediment that has been tracked onto
roadways to reduce sediment transport
into storm drain systems or a surface
waterway.
Appropriate Uses
Use this practice at construction sites
where vehicles may track sediment
offsite onto paved roadways.
Design and Installation
Street sweeping or vacuuming should be
conducted when there is noticeable
Photograph SS-1. A street sweeper removes sediment and potential
pollutants along the curb line at a construction site. Photo courtesy of
Tom Gore.
sediment accumulation on roadways adjacent to the construction site. Typically, this will be concentrated
at the entrance/exit to the construction site. Well-maintained stabilized construction entrances, vehicle
tracking controls and tire wash facilities can help reduce the necessary frequency of street sweeping and
vacuummg.
On smaller construction sites, street sweeping can be conducted manually using a shovel and broom.
Never wash accumulated sediment on roadways into storm drains.
Maintenance and Removal
•
•
Inspect paved roads around the perimeter of the construction site on a daily basis and more
frequently, as needed. Remove accumulated sediment, as needed.
Following street sweeping, check inlet protection that may have been displaced during street
sweepmg.
• Inspect area to be swept for materials that may be hazardous prior to beginning sweeping operations .
November 2010
Street Sweeping/ Vacuuming
-_ : . . ·, . ' Functions,_ ' . ' '
..
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
" .,
'
No
Yes
Yes
SS-1
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Dewatering Operations (DW)
Description
The BMPs selected for construction
dewatering vary depending on site-
specific features such as soils,
topography, anticipated discharge
quantities, and discharge location.
Dewatering typically involves pumping
water from an inundated area to a BMP,
and then downstream to a receiving
waterway, sediment basin, or well-
vegetated area. Dewatering typically
involves use of several BMPs in
sequence.
. .
··, .. ·
. '' ~ ~ .. -.
•~ • ,l_-"_..,. ., . ' . . -~Ji;:..>~>'\.
SM-9
Appropriate Uses
Photograph DW-1. A relatively small dewatering operation using straw
bales and a dewatering bag.
Dewatering operations arc used when an
area of the construction site needs to be
dewatered as the result of a large storm
event, groundwater, or existing ponding
conditions. This can occur during deep
excavation, utility trenching, and wetland
or pond excavation.
Design and Installation
Dewatering techniques will vary
depending on site conditions. However,
all dewatering discharges must be treated
to remove sediment before discharging
from the construction site. Discharging
water into a sediment trap or basin is an
acceptable treatment option. Water may
also be treated using a dewatering filter bag,
Photograph DW-2. Dewatering bags used for a relatively large
dewatering operation.
and a series of straw bales or sediment logs. If these previous options are not feasible due to space or the
ability to passively treat the discharge to remove sediment, then a settling tank or an active treatment
system may need to be utilized. Settling tanks are manufactured tanks with a series of baffles to promote
settling. Flocculants can also be added to the tank to induce more rapid settling. This is an approach
sometimes used on highly urbanized construction sites. Contact the state agency for special requirements
prior to using flocculents and land application techniques.
Some commonly used methods to handle the pumped
water without surface discharge include land application
to vegetated areas through a perforated discharge hose
(i.e., the "sprinkler method") or dispersal from a water
truck for dust control.
Dewaterinl! Ooerations
November 20 l 0
Functions. .
Erosion Control
Sediment Control
Site/Material Management
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
•.
Moderate
Yes
Yes
DW-1
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SM-9 Dewatering Operations (DW)
Dewatering discharges to non-paved areas must minimize the potential for scour at the discharge point
either using a velocity dissipation device or dewatering filter bag.
Design Details are provided for these types of dewatcring situations:
DW-1. Dewatering for Pond Already Filled with Water
DW-2 Dcwatering Sump for Submersed Pump
DW-3 Sump Discharge Settling Basin
DW-4 Dewatering Filter Bag
Maintenance and Removal
When a sediment basin or trap is used to enable settling of sediment from construction dewatering
discharges, inspect the basin for sediment accumulation. Remove sediment prior to the basin or trap
reaching half full. Inspect treatment facilities prior to any dewatering activity. If using a sediment
control practice such as a sediment trap or basin, complete all maintenance requirements as described in
the fact sheets prior to dewatering.
Properly dispose ofused dewatering bags, as well as sediment removed from the dewatering BMPs.
Depending on the size of the dewatering operation, it may also be necessary to revegetate or otherwise
stabilize the area where the dewatering operation was o~curring.
DW-2 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Dewatering Operations (DW) SM-9
LID WITH HOLE CUT
FOR SUCTION LINE 8
DW-1. DEWATERING POND ALREADY FILLED WITH WATER
LOWEST SUBGRADE
-- - - - - - -___,,,,-ELEVATION TO BE DEWATERED
PUMP SUCTION LINE OR LID WITH HOLE CUT I 2 ' MIN.
SUBMERSIBLE PUMP FOR SUCTION ~
12" MIN. AROUND ON
ALL SIDES OF BUCKET
12" MIN.
BELOW BUCKET
PLASTIC 5-GALLON BUCKET WITH
MANY 3/8" HOLES DRILLED IN SIDES
AND BOTTOM
MSHTO #3 GRAVEL
(COOT SECT. 703, #3)
DW-2. DEWATERING SUMP FOR SUBMERSED PUMP
DEWATERING PUMP
DISCHARGE LINE
4' MIN.
SETTLING POND
SURFACE AREA, "A"
1 SF PER 1 GPM
12"
MIN. 2' MIN.
12"
STAKES TO RIPRAP
SECURE END OF } T D50=6"
12" r MIN.
MIN~
12" DISCHARGE LINE , 2 x D50
2 MIN. ,
4' (MIN.) SQUARE MIN. ( 12' MIN)
RIPRAP PAD TO STABILIZE FLOW PATH
DISSIPATE THE TO OUTFALL OR
ENERGY OF THE RECEMNG WATERS
FLOW EXITING THE
DISCHARGE LINE
DW-3. SUMP DISCHARGE
SETTLING BASIN
r~
050=6"
SETTLING BASIN
SECTION A
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
DW-3
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SM-9
SEDIMENT CONTROL LOG
(SEE SCL-1 DETAIL)
ROCK WILL BE INSTALLED,
AS NECESSARY, TO
Dewatering Operations (DW)
PREVENT EROSIO.'.:N-;-;;;:;;-;;;-;;i;-;_-'-"");/q
DISCHARGE PIPE
DW-4
FILTER BAG ON
STRAW BALES
OR ROCK PAO
DW-4. DEWATERING FILTER BAG
PEWATER!NG INSTALLATION NOTES
1. SEE PLAN VIEW FOR:
-LOCATION OF DEWATERING EQUIPMENT.
-TYPE OF DEWATERING OPERATION (DW-1 TO DW-4).
2. THE OWNER OR CONTRACTOR SHALL OBTAIN A CONSTRUCTION DISCHARGE (DEWATERING)
PERMIT FROM THE STATE PRIOR TO ANY DEWATERING OPERATIONS DISCHARGING FROM THE
SITE. ALL DEWATERING SHALL BE IN ACCORDANCE WITH THE REQUIREMENTS OF THE PERMIT.
3. THE OWNER OR OPERATOR SHALL PROVIDE. OPERATE, AND MAINTAIN DEWATERING SYSTEMS
OF SUffiCIENT SIZE AND CAPACITY TO PERMIT EXCAVATION AND SUBSEQUENT CONSTRUCTION
IN DRY CONDITIONS AND TO LOWER AND MAINTAIN THE GROUNDWATER LEVEL A MINIMUM OF
2-FEET BELOW THE LOWEST POINT OF EXCAVATION AND CONTINUOUSLY MAINTAIN EXCAVATIONS
FREE OF WATER UNTIL BACK-FILLED TO FINAL GRADE.
Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
November 2010
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Dewatering Operations (DW) SM-9
DEWATFRING INSTALWION NOTES
4. DEWATERING OPERATIONS SHALL USE ONE OR MORE OF THE DEWATERING SUMPS SHOWN
ABOVE, WELL POINTS, OR OTHER MEANS APPROVED BY THE LOCAL JURISDICTION TO REDUCE
THE PUMPING OF SEDIMENT, AND SHALL PROVIDE A TEMPORARY SEDIMENT BASIN OR
FILTRATION BMP TO REDUCE SEDIMENT TO ALLOWABLE LEVELS PRIOR TO RELEASE OFF SITE
OR TO A RECEIVING WATER. A SEDIMENT BASIN MAY BE USED IN LIEU OF SUMP DISCHARGE
SETTLING BASIN SHOWN ABOVE IF A 4-FOOT-SQUARE RIPRAP PAD IS PLACED AT THE
DISCHARGE POINT AND THE DISCHARGE END OF THE LINE IS STAKED IN PLACE TO PREVENT
MOVEMENT OF THE LINE.
DEWATERING MAINTENANCE NOTES
1. INSPECT BMPs EACH WORKDAY. AND MAINTAIN THEM IN EFFECTIVE OPERATING CONDITION.
MAINTENANCE OF BMPs SHOULD BE PROACTIVE, NOT REACTIVE. INSPECT BMPs />S SOON AS
POSSIBLE (AND ALWAYS WITHIN 24 HOURS) FOLLOWING A STORM THAT CAUSES SURFACE
EROSION, AND PERFORM NECESSARY MAINTENANCE.
2. FREQUENT OBSERVATIONS AND MAINTENANCE ARE NECESSARY TO MAINTAIN BMPs IN
EFFECTIVE OPERATING CONDITION. INSPECTIONS AND CORRECTIVE ME/>SURES SHOULD BE
DOCUMENTED THOROUGHLY.
3. WHERE BMPs HAVE FAILED, REPAIR OR REPLACEMENT SHOULD BE INITIATED UPON
DISCOVERY OF THE FAILURE.
4. OEWATERING BMPs ARE REQUIRED IN ADDITION TO ALL OTHER PERMIT REQUIREMENTS.
5. TEMPORARY SETTLING BASINS SHALL BE REMOVED WHEN NO LONGER NEEDED FOR
OEWATERING OPERATIONS. ANY DISTURBED AREA SHALL BE COVERED WITH TOPSOIL, SEEDED
ANO MULCHED OR OTHERWISE STABILIZED IN A MANNER APPROVED BY THE LOCAL
JURISDICTION.
NOTE: MANY JURISDICTIONS HAVE BMP DETAILS THAT VARY FROM UDFCO STANDARD DETAILS.
CONSULT WITH LOCAL JURISDICTIONS AS TO WHICH DETAIL. SHOULD BE USED WHEN
DIFFERENCES ARE NOTED.
(DETAILS ADAPTED FROM DOUGLAS COUNTY, COLORM)Q, NOT AVAILABLE IN AUTOCAD)
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
DW-5
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Temporary Batch Plant (TBP) SM-11
Description
Temporary batch plant management
includes implementing multiple BMPs
such as perimeter controls, concrete
washout area, stabilized construction
access, good housekeeping, and other
practices designed to reduce polluted
runoff from the batch plant area.
Appropriate Uses
Implement this BMP at temporary batch
plants and identify the location of the
batch plant in the SWMP. Photograph TBP-1. Effective stormwater management at temporary
batch plants requires implementation of multiple BMPs. Photo
Additional permitting may be required for courtesy of California Stormwater BMP Handbook.
the operation of batch plants depending on their duration and location.
Design and Installation
The following lists temporary management strategies to mitigate runoff from batch plant operations:
•
•
•
When stockpiling materials, follow the Stockpile Management BMP.
Locate batch plants away from storm drains and natural surface waters .
A perimeter control should be installed around the temporary batch plant.
• Install run-on controls where feasible.
•
•
•
A designated concrete washout should be located within the perimeter of the site following the
procedures in the Concrete Washout Area BMP.
Follow the Good Housekeeping BMP, including proper spill containment measures, materials
storage, and waste storage practices.
A stabilized construction entrance or vehicle tracking control pad should be installed at the plant
entrance, in accordance with the Vehicle Tracking Control BMP.
Maintenance and Removal
Inspect the batch plant for proper functioning of the BMPs, with
attention to material and waste storage areas, integrity of
perimeter BMPs, and an effective stabilized construction
entrance.
Temporary Batch Plants
,iuncrto11s '
' __ ,, ,·
' '. ' . ·,\. , ~-, -~-C •••
Erosion Control
Sediment Control
Site/Material Management
,,,,;' ','\
;, ,-.-
No
No
Yes
November 2010 Urban Drainage and Flood Control District
Urban Storm Drainage Criteria Manual Volume 3
TBP-1