HomeMy WebLinkAboutDrainage Reports - 10/01/20131
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PIKE
11111AThis Drainage Report is consciously provided as a PDF.
Please consider the environment before printing this document in its entirety.
When a hard copy is absolutely necessary, we recommend double -sided printing.
September 23, 2013
City of Ft. ColnpPlana
Approved By
Date 1 0 —1' f 3
Prepared for:
West Range Fort Collins, LLC
8347 West Range Cove
Memphis, TN 38125
Prepared by:
NORTHERN
ENGINEERING
200 South College Avenue, Suite 10
Fort Collins, Colorado 80524
Phone, 970.221.4158 Fax; 970.221.4159
wwv .nonhemengineenng.com
Project Number: 875-001
Nn.rhernF nni nrwr inn rnm it 07n 771 41 CA
I
' ■� NORTHERN
ENGINEERING
' September 23, 2013
' City of Fort Collins
Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
' RE: Final Drainage Report for
West Range Fort Collins
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Dear Staff:
ADDRESS: PHONE:970.221.4158
200 S. College Ave. Suite 10 WEBSITE:
Fort Collins, C080524 FAX:970.221.4159 www.northernengineering.com
Northern Engineering is pleased to submit this Final Drainage Report for your review.
Comments from the FDP130022 review letter dated 06.28.13 have been addressed.
Written responses thereto can be found in the comprehensive response to comments letter
on file with Current Planning.
This report has been prepared in accordance with the Fort Collins Stormwater Criteria
Manual (FCSCM), and serves to document the stormwater impacts associated with the
proposed West Range Fort Collins student housing 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.
Nicholas W. Haws, PE LEED
Vice President AP
1
NORTHERN
E N G I N E E R Nc West Range Fort Collins
1
TABLE OF CONTENTS
1
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I. GENERAL LOCATION AND DESCRIPTION......................................................... 1
Il. DRAINAGE BASINS AND SUB-BASINS.............................................................
5
III. DRAINAGE DESIGN CRITERIA.........................................................................
7
'
IV. DRAINAGE FACILITY DESIGN..........................................................................
9
V. CONCLUSIONS............................................................................................
12
'
References.............................................................................................................
APPENDICES:
13
'
APPENDIX A — Hydrologic Computations
APPENDIX B — Hydraulic Computations I Detention Facilities
APPENDIX C — Water Quality Design Computations
APPENDIX D — Operations and Maintenance Guidelines for Rain Gardens
LIST OF TABLES AND FIGURES:
'
Figure 1 — Vicinity Map .......................... ... .............................------------- ................
Figure 2 — Aerial Photograph .......................................................................................
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Figure 2 — Existing Drainage and Irrigation Infrastructure --------------------------------------------
3
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Figure 4 — FEMA Firmette (Map Number 08069CO979H)........................................
4
Table 1 — Existing and Proposed Runoff Rate Comparison......... ............. ...............11
'
MAP POCKET:
C4.00 — Drainage Exhibit (West Range Fort Collins I Northern Engineering)
1
1 of 2 — Phase 1 Grading, Drainage and Erosion Control Plan (Shear Engineering)
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Final Drainage Report
■� NORTHERN
E N G I NE E RI NG
West Range Fort Collins
1
I. GENERAL LOCATION AND DESCRIPTION
A. Location
1. Vicinity Map
MOUNTAIN AVE.
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Figure 1 — Vicinity Map
2. The West Range Fort Collins project site is located in the Northeast quarter of Section
11, Township 7 North, Range 69 West of the 6In Principal Meridian, City of Fort
Collins, County of Larimer, State of Colorado.
3. West Range Fort Collins is bordered to the north by an existing alleyway and existing
multi -family and single-family developments; to the south by West Laurel Street and
Colorado State University; to the east by Meldrum Street (100' Right -of -Way); and to
the west by the Kappa Delta Sorority house.
4. There are no major drainageways within or adjacent to the site. The existing Arthur
Ditch runs parallel to the east property line. As it approaches the north property line,
the enclosed concrete irrigation ditch alignment shifts to the northwest. This irrigation
ditch receives excess developed stormwater from two existing inlets near the project
site. The ditch's concrete top slab is at grade, visible and currently used for a sidewalk
along the west side of Meldrum Street.
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Final Drainage Report 1
F
N NORTHERN
ENGINEERING West Range Fort Collins
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B. Description of Property
1. West Range Fort Collins is comprised of ±0.71 acre.
The recent existing condition (See Figure 2 - Aerial Photograph) included: two (2)
fraternity houses that fronted to West Laurel Street, a detached garage and a duplex
that fronted to Meldrum Street. The asphalt parking lot was constructed in the mid-
1990s as a part of the Phase I condition described in the Final Drainage and Erosion
Control Report for the Pi Kappa Alpha Fraternity Expansion (Shear Engineering:
Phase I, Sheet No. 1 - Phase I Grading, Drainage and Erosion Control Plan is provided
for reference in the Map Pocket of the report). The ultimate condition described in the
drainage report was never constructed.
Figure 2 — Aerial Photograph
3. The subject property was fully developed until the late fall of 2011. At that time,
everything was removed from the property except for the asphalt parking lot
(northwest corner), concrete curb and gutter and several mature trees.
The existing groundcover currently consists of weeds and bare soil. The existing on -site
excess runoff drains across flat grades (e.g., <2.00%) into West Laurel Street,
Meldrum Street and the alleyway.
4. A soils report (Soilogic Project # 08-1051) was completed by Soilogic, Inc. on
September 29, 2008. The report contains the results of a complete geotechnical
subsurface exploration as well as pertinent geotechnical recommendations. According
to the summary of findings presented in the aforementioned report, the "subsurface
materials encountered in the completed site borings consisted of a thin layer of
asphaltic concrete and base course or topsoil and vegetation underlain by brown to
reddish brown lean clay with varying amounts of silt and sand. A majority of the site
Final Drainage Report
.V INORTHERN
ENGINEERING
West Range Fort Collins
lean clay tested showed low volume change potential with variation in moisture
content at in -situ moisture and density conditions. Lean clay with low to moderate
swell potential was encountered near surface boring location B-1 completed at the
south end of the development. Groundwater was not encountered in any of the
completed site borings at the time of drilling."
The boring logs show that USCS soil group CL is predominant on -site. These soils are
inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays and
lean clays.
5. There are no major drainageways within or adjacent to the project site.
6. The proposed West Range Fort Collins project site will include a single backwards L-
shaped building with a plan area of approximately 8000 ft2. The completed structure
will be two stories. Other proposed improvements include: a new concrete parking
area, an enhanced entryway and landscaping. The north -to -south portion of the
proposed building will include an open first level (i.e., breezeway) beneath which
approximately one-half of the total on -site parking will be located.
7. The existing Arthur Ditch runs parallel to the east property line. As it approaches the
northeast corner of the subject site, the concrete box alignment shifts toward the
northwest (See Figure 3 — Existing Drainage and Irrigation Infrastructure).
Figure 3 — Existing Drainage and Irrigation Infrastructure
S. The proposed land use is residential, multi -family dwellings. This is a permitted use in
the Neighborhood Community - Buffer District (NCB).
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Final Drainage Report 3
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' ,� ~' NORTHERN
E BGI XE E R I xG West Range Fort Collins
C. Floodplain
1. The subject property is not located in a FEMA regulatory or City of Fort Collins
designated Floodplain. In particular, the project site is not located within a FEMA
' designated 100-year floodplain per Map Number 08069CO979H (Effective date: May
2, 2012).
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Figure 4 — FEMA Firmette (Map Number 08069C0979H)
Final Drainage Report 4
N NORT_HER.N
West Range Fort Collins
1
DRAINAGE BASINS AND SUB -BASINS
A. Major Basin Description
West Range Fort Collins is located within the City of Fort Collins Old Town major
drainage basin. This basin is located in north -central Fort Collins and has a drainage
area of approximately 2,120 acres, including approximately 400 acres of the Colorado
State University campus. The Old Town major drainage basin generally drains from
west to east. It receives some runoff from the Canal Importation Basin directly west of
Old Town. Most of the runoff from the Old Town major drainage basin drains into the
Poudre River.
Street flooding is a common occurrence in Old Town. Several capital projects such as
the Howes Street, Locust Street and Oak Street Outfall projects have addressed the
problem and improved drainage in the area.
2. As previously mentioned, the Arthur Ditch runs parallel to the east property line. This
irrigation conveyance receives existing flows from the project site (Shear Engineering:
sub -basins la and lc). Excess developed runoff from the subject site will continue to
outfall into this irrigation conveyance as described below.
B. Sub -Basin Description
Shear Engineering, in the Final Drainage and Erosion Control Report for the Pi Kappa
Alpha Fraternity Expansion, described and evaluated an existing condition, Phase I
condition and Ultimate condition. The existing condition was used to establish the
historic release rate. Phase I represented an interim developed condition in which the
existing gravel parking lot was paved and used for on -site detention storage. The pond
was designed to overdetain (i.e., the total site area was used to size the pond instead
of the total area tributary to the pond) and release at the historic 2-year rate (0.50
cfs). The Ultimate condition was never constructed.
2. The existing site was defined by three (3) sub -basins (i.e., la. lb and Ic). Runoff
drained in three directions from the center of each of the three (3) previously existing
structures. First, runoff from the east portion (sub -basin lb) of the project site drained
into Meldrum Street and travelled north. Second, runoff from the south portion (sub -
basin lc) of the subject site drained into West Laurel Street. From there, flows
traveled east via curb and gutter and into an existing combination inlet. Excess runoff
from the central and northwest portion of the subject site (sub -basin la) currently
drains across the existing asphalt parking lot and into an existing outlet structure. This
structure outfalls to the storm drain system in the alleyway.The West Range Fort
Collins development aims to preserve these existing drainage patterns and will utilize
the existing outfall location.
3. The Arthur Ditch receives developed stormwater runoff from the subject site at two
locations. First, at an existing combination inlet located on the north side of West
Laurel Street (west of Meldrum Street). This inlet is connected to the ditch with a 10"
diameter metal pipe. In addition to local developed runoff from West Laurel Street, the
combination inlet received developed stormwater runoff from the Phase I developed
condition sub -basin Ic. Developed runoff, which is similar in peak rate, will drain to
this existing inlet from sub -basin C.
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Final Drainage Report
' NORTHERN
E NG INEE RI NC
West Range Fort Collins
1
The proposed on -site quantity detention pond will outfall at 0.50 cfs (historic 2-year
release rate) into the existing public storm sewer system in the alleyway. This system
ultimately drains to the Arthur Ditch. A more detailed description of the project's
' drainage patterns follows in Section IV, below.
4. The project site does not receive any notable runoff from off -site properties.
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Final Drainage Report
M
N NORTHERN '
West Range Fort Collins
III. DRAINAGE DESIGN CRITERIA '
A. There are no optional provisions outside of the FCSCM proposed with West Range Fort '
Collins.
S. The overall stormwater management strategy employed with West Range Fort Collins
'
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. The first consideration taken in trying to
reduce the stormwater impacts of this development is the site selection itself. By choosing
,
an already developed site with public storm sewer currently in place, the burden is
significantly less than developing a vacant parcel absent of any infrastructure.
'
West Range Fort Collins aims to reduce runoff peaks, volumes and pollutant loads from
frequently occurring storm events (i.e., water quality (801" percentile) and 2-year storm
events) by implementing Low Impact Development (LID) strategies. Wherever practical,
'
runoff will be routed across landscaped areas or through a grass -lined swale and bio-
retention area. This LID practice reduces the overall amount of impervious area, while
Minimizing Directly Connected Impervious Areas (MDCIA) at the same time. The
'
combined LID/MDCIA techniques will be implemented, where practical, throughout the
development, thereby slowing runoff and increasing opportunities for infiltration.
'
Step 2 — Implement BMPs That Provide a Water Quality Capture Volume (WQCV) with
Slow Release. The efforts taken in Step 1 will help to minimize excess runoff from
frequently occurring storm events; however, urban development of this intensity will still
have stormwater runoff leaving the site. The primary water quality will occur in a linear
,
bio-retention area along the northwest property line (sub -basin A). Refer to Appendix C for
a schematic cross-section of the proposed bio-retention area.
'
Step 3 — Stabilize Drainageways. As stated in Section 1.B.5, above, there are no major
drainageways in or near the subject site. While this step may not seem applicable to West
Range Fort Collins, the proposed project indirectly helps achieve stabilized drainageways
nonetheless. Once again, site selection has a positive effect on stream stabilization. By
repurposing an already developed, under-utilized site with existing stormwater
infrastructure, combined with LID and MDCIA strategies, the likelihood of bed and bank
'
erosion is greatly reduced. Furthermore, this project will pay one-time stormwater
development fees, as well as ongoing monthly stormwater utility fees, both of which help
achieve Citywide drainageway stability.
'
Step 4 — Implement Site Specific and Other Source Control BMPs. This step typically
applies to industrial and commercial developments.
'
C. Development Criteria Reference and Constraints
1. The subject property is not part of any Overall Development Plan (ODP) drainage
'
study or similar "development/project" drainage master plan.
2. There are no known drainage studies for any adjacent properties that will have an
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effect on the West Range Fort Collins project. The Final Drainage and Erosion Control
Report for the Pi Kappa Alpha Fraternity Expansion (Shear Engineering, 1995) was
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Final Drainage Report 7
.V NORTHERN
ENGINEERING West Range Fort Collins
' referenced during the preparation of this study. The contents of the report served as
' the basis for developing our existing drainage conditions, existing pervious/impervious
areas, release rate and the existing detention pond volume that was associated with
the previous development.
'
3.
The site plan will be constrained on two sides by public streets and by an alleyway on
the third. An existing and fully developed site constrains the site plan on the fourth. As
previously mentioned, the drainage outfall for Basin A is an existing manhole that ties
into an existing 12" RCP storm sewer in the alleyway. The release rate proposed
herein matches the existing release rate of 0.50 cfs.
'
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 West Range Fort Collins 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 RO-11 and RO-12 of the FCSCM.
3.
The Rational Formula -based Federal Aviation Administration (FAA) procedure was
utilized for detention storage calculations.
'
4.
Two separate design storms have been utilized to address distinct drainage scenarios.
The first event analyzed is the "Minor," or "Initial" Storm, which has a 2-year
recurrence interval. The second event considered is the "Major Storm". It has a 100-
'
year recurrence interval.
' E. Hydraulic Criteria
1. The drainage facilities proposed with the West Range Fort Collins project are
' designed in accordance with criteria outlined in the FCSCM and/or the Urban
Drainage and Flood Control District's (UDFCD) Urban Storm Drainage Criteria
Manual.
' 2. As stated in Section I.C.1, above, the subject property is not located in a
FEMA regulatory or a City of Fort Collins designated floodplain.
F. Floodplain Regulations Compliance
1. As previously mentioned, this project is not subject to any floodplain
' regulations.
G. Modifications of Criteria
' 1. No modifications are requested at this time.
1
Final Drainage Report
(NORTHERN '
ENGINEERING
West Range Fort Collins
IV. DRAINAGE FACILITY DESIGN ,
A. General Concept '
1. The main objective of the West Range Fort Collins drainage design is to maintain ,
existing drainage patterns, while not adversely impacting adjacent properties.
2. No notable off -site runoff flows directly through the project site. '
3. A list of tables and figures used within this report can be found in the Table of
Contents at the front of this document. The tables and figures are located within the '
sections to which the content best applies.
4. The project site has been divided into three (3) drainage sub -basins, designated as
sub -basins A, B and C. The drainage patterns anticipated for each basin are further
described below.
Sub -Basin A '
Sub -basin A encompasses a little over one-half of the total project site area. It is
comprised of roof area, concrete walks and parking. A large part of the parking area in
this basin will comprise the on -site detention pond (Pond A). D.P. A is situated at the '
proposed outfall. A short section of pipe will connect to an existing manhole in the
alleyway. This basin releases at the existing rate of 0.50 cfs.
Sub -Basin B t
Sub -basin B encompasses the eastern third of the project site. It is comprised of roof
area, a concrete patio and landscaping. The downspouts will direct developed runoff ,
from the roof into the landscaping. The excess developed runoff will primarily drain
into Meldrum Street as sheet flow (i.e., non -concentrated). The developed flows in this
basin are similar to the existing (i.e., Phase 1) condition. During the 2-year and 100- ,
year storm events, the proposed condition decreases runoff into Meldrum Street by
±0.08cfs and ±0.36cfs, respectively.
Sub -Basin C '
Sub -basin C is very similar in composition to Basin B. It is situated along the south
portion of the subject site. The excess developed runoff will primarily drain into West '
Laurel Street as sheet flow. In West Laurel Street, the runoff drains into an existing
combination inlet which is connected to the Arthur Ditch. During the 2-year and 100-
year storm events, the proposed condition increases runoff into Meldrum Street by '
t0.08cfs and tO.35cfs, respectively.
A full-size copy of the Drainage Exhibit (sheet C4.00) can be found in the Map Pocket '
at the end of this report.
B. Specific Details ,
1. The FAA method was used to size the on -site pond for quantity detention. The
Phase I quantity detention volume (computed by Shear Engineering - 1995) '
was 2756 ft3. This quantity storage volume calculation was based on the total
site area (i.e., 0.71 acre) and a historic release rate of 0.50 cfs. Our design
approach and FAA method calculation includes only sub -basin A. The required ,
Final Drainage Report 9
NORTHERN
ENGINEERING
West Range Fort Collins
' 100-year quantity detention volume is 2957 cf. ft. To this, we added the
' available Water Quality Capture Volume of 261 cu. ft. and arrived at a total
pond volume of 3218 cu. The corresponding 100-year Water Surface
Elevation (WSE) is 5001.40. The total ponding depth, at the lowest curb cut
is 1.07 feet. The approximate area for which the depth will exceed one foot is
17 sq. ft. The impact associated a ponding depth 0.07 foot greater than one
foot is negligible.
' 2. Design calculations for the proposed bio-retention area in sub -basin A were completed
using the UDFCD's UD-BMP Version 3.01 "Rain Garden (RG)" Design Procedure
Form. Calculations for this area, based on the characteristics of sub -basin A, indicate
a required volume of 461 cu. ft. The maximum volume available, above the proposed
finished grade, is approximately 261 cu. ft. We are proposing to provide the remaining
volume in twelve inches of No. 57 stone beneath the six to twelve inch layer of Fort
' Collins Bioretention Sand Media (BSM) mix. Refer to Appendix C for a schematic
cross-section of the proposed bio-retention area.
' Site constraints, which include a shallow storm drain outfall (4999.41) and a low
adjacent parking lot finished grade (5000.33), only allow for a total ponding depth at
the outlet of eleven inches. A fully developed bio-retention section generally requires at
' least eighteen inches for just the bio-retention soil media.
The proposed water quality area is:
' • Designed to maximize available volume without ponding water in the parking
area during water quality events
• Release this volume over 12-hours
' The aforementioned constraints also eliminate the possibility for installing an
underdrain. The area will infiltrate nuisance flows and allow sediment to settle during
' water quality rain events.
The Fort Collins BSM mix will be used in the base of the water quality area. Tree
' plantings within this area as well as those in close proximity are less of an issue
because an underdrain is not being proposed.
' 3. The detention storage information for Pond 1 is contained in Appendix B. The
drainage features associated with West Range Fort Collins project are private
facilities and located on private property.
' 4. As previously mentioned, the outfall for the West Range Fort Collins project is the
public storm sewer in the neighboring alleyway. This storm sewer flows northwest to
' an existing area inlet before heading north towards Myrtle Street. As shown above in
Figure 3, this storm drain outfalls into the Arthur Ditch. There are no additional
facilities or upgrades needed off -site in order to accommodate the developed runoff
' from West Range Fort Collins.
5. The net effect of West Range on existing runoff rates is zero during the 2-, 10- and
' 100-year storm events (see below). Note that the Phase I flows used for comparison
were re -calculated using the current City of Fort Collins Intensity -Duration -Frequency
curve.
Final Drainage Report 10
NORTHERN 1
ENGINEERING West Range Fort Collins
Table 1 — Existing and Proposed Runoff Rate Comparison 1
Design Point
Runoff Comparison (Pro
` ,y
Q
Q
Q101)
A la
0.00
0.00
0.00
B lb
-0.08
-0.14
-0.36
C Ic
0.08
0.14
0.35
Net Change:
0.00
0.00
-0.01
1
1
1
In particular, there is no change in sub -basin A because the quantity detention release
rate will remain the same. The developed runoff in sub -basin B, which drains into 1
Meldrum Street, decreased. The runoff draining to Laurel Street will increase during
each of the storm events; however, the magnitude of the increase is negligible relative
to the size of each storm event. 1
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Final Drainage Report 11
11C I NORM HERN
ENGIEERING West Range Fort Collins
1 V. CONCLUSIONS
1 A. Compliance with Standards
1 1. The design elements comply without variation.
2. The drainage design proposed with West Range Fort Collins complies with the City of
1 Fort Collins Master Drainage Plan for the Old Town Basin.
3. There are no regulatory floodplains associated with the West Range Fort Collins
1 development.
4. The drainage plan and stormwater management measures proposed with the West
Range Fort Collins student housing project are compliant with all applicable State and
1 Federal regulations governing stormwater discharge.
B. Drainage Concept
1 1. The drainage design proposed with this project will effectively limit potential damage
associated with its stormwater runoff.
1 2. The proposed West Range Fort Collins development will not impact the Master
Drainage Plan recommendations for the Old Town Basin.
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Final Drainage Report
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NORTHERN '
E N GI NEE R I Nc West Range Fort Collins
References
I
1. City of Fort Collins Landscape Design Guidelines for Stormwater and Detention Facilities, '
November 5, 2009, BHA Design, Inc. with City of Fort Collins Utility Services.
2. Final Drainage and Erosion Control Report for Pi Kappa Alpha Fraternity Exoansion, October '
1995, Shear Engineering Corporation (Project No. 1060-02-95).
3. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, as adopted by Ordinance No. '
174, 2011, and referenced in Section 26-500 (c) of the City of Fort Collins Municipal Code.
4. Geotec_hnical_Exploration Report, Pike Redevelopment, 406 West Laurel Street, Fort Collins. ,
Colorado, September 29, 2008, Soilogic, Inc. (Soilogic # 08-1051).
5. Soils Resource Report for Larimer County Area, Colorado, Natural Resources Conservation '
Service, United States Department of Agriculture.
6. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control '
District, Wright -McLaughlin Engineers, Denver, Colorado, Revised April 2008.
Final Drainage Report
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N orth ernEnaineerin a.com N 970.221.4158
NORTHERN
ENGINEERING
West Range Fort Collins
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SUMMARY OF EXISTING AND PROPOSED IMPERVIOUS AREA
Areas, sq, It.
Project:
West Range Fort Collins
Project Site Area 30927.6
Calculations
By:
H. Feissner
'
la 14810.40
Date:
December 12, 2012
lb 10454.40
Ic 5662.80
A 19886.42
B 5516.79
'
C 5394,34
EXISTING CONDITION
Basin
Area, sq. ft, Surface Description % Impervious.
Area, sq. ft.
Notes
'
la
6969.6 Asphalt
100%
6970
Id
2178.0 Roofs
90%
1960
Impervious Area
8930
% Impervious
60 %
'
Ib
871.2 Concrete (e.g.,
walks & parking) 90%
784
lb
217B.0 Concrete (e.g.,
walks & parking) 90%
1960
Impervious Area
2744
'
%Impervious
26%
Ic
435.6 Concrete (e.g.,
walks & parking) 90%
392
Ic
1306.8 Pavers (e.g., wood deck) 22 %
287
'
Impervious Area
%Impervious
680
12%
Total Impervious Area
12354
% Impervious
40%
PROPOSED CONDITION
Basin
Area, sq. ft. Surface Description % Impervious
Area, sq, ft.
Notes
A
5272.39 Asphalt
100%
5272
'
A
A
3665.45 Concrete
8801.00 Roofs
90%
90%
3299
7921
Impervious Area
16492
% Impervious
83%
B
189.76 Asphalt
100%
190
'
B
723.44 Concrete
90%
651
B
1568.02 Roofs
90%
1411
Impervious Area
2252
'
C
0 Asphalt
% Impervious
100%
42%
0
C
954.97 Concrete
90%
859
C
2354.16 Roofs
90%
2119
Impervious Area
2978
'
% Impervious
55 %
Impervious Area
21722
% Impervious
70%
'
SUMMARY
Areas .fl. I
Area, acre
Total Impervious Area Increase
9369
215
12/12/2012 12:09 PM
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North ernE noineerina.mm 11 970.221.4158
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11
■� I NORTHERN
ENGINEERING
West Range Fort Collins
Detention Pond Calculation I FAA Method
Project Number:
;`:
Project Location:
I
Calculations By:
11,
Date:
12/12/2012
Pond No.:
Input Variables
Results
Design Point
Design Storm
Required Detention Volume
Developed "C' =
WQCV 0 ftZ
Area(A)=
G.i6
acres
2957 ft3
Max
Release Rate =
0 50
cfs
0.0679 ac•ft
Ft.Col I i ns
Inflow
Storage
Time
Time
100-yr
Q100
(Runoff)
Outflow
Detention
(Release) Volume
Intensity
Volume
Volume
(mins)
(secs)
(in/hr)
(cfs)
(ft)
(ft)
(ft )
5
300
9.95
4.6
1373
150
1223
10
600
7.72
3.6
2131
300
1831
15
900
6.52
3.0
2699
450
2249
20
1200
5.60
2.6
3091
600
2491
25
1500
4.98
2.3
3436
750
2686
30
1800
4.52
2.1
3743
900
2843
35
2100
4.08
1.9
3941
1050
2891
40
2400
3.74
1.7
4129
1200
2929
45
1 2700
3.46
1.6
4297
1350
2947
50
000
3.23
1.5
4457
1500
2957
55
3300
3.03
1.4
4600
1650
2950
60
3600
2.86
1.3
4736
1800
2936
65
1 3900
2.72
1.3
4880
1950
2930
1
12/12/2012 11:37 AM D:IProjectsl875-0011DrainagelDetention1875-001—Detention Pond.xlsmlfAA_Current idf
N NORTHERN
ENGINEERING
West Range Fort Collins
Stage - Storage Calculation
Project Number:
875-001
Project Location:
Fort Cnl..i
Calculations By:
H I er
Date:
1211212012
Pond No.:
f
Required Volume
Water Surface Elevation (WSE)
Design Point
Design Storm
Require Volume=
Gol
ft,
• • ft.
Design Storm
100-/r
Required Volume=
3218
ft3
r ft.
Contour
Cummulative
Contour
Incremental Area
Cumulative Volume
Incremental Volume
Elevation (Y
Depth
Volume
Conic (X-
Area
Avg. End
Avg. End
Conic
values)
values)
ft
ft.
ft
ft
ft3
ft
4,999.60
93
0.00
0
0
0
0
4,999.80
254
0.20
35
35
33
33
5,000.00
400
0.20
65
100
65
98
5,000.20
486
0.20
89
189
88
187
5,000.40
560
0.20
105
293
104
291
5,000.60
1063
0.20
162
456
160
451
5,000.80
1996
0,20
306
761
301
752
5,001.00
3355
0.20
535
1297
529
1281
5,001.20
4924
0.20
828
2124
823
2104
6504
0.20
1143
3267
1139
3243
h55,001.40
,001.60
8071
0.20
1457
4725
1455
4698
5,002.00 —
5,001.50
e 5,001.00--
W
5,000.50
U
5,000.00
4,999.50 -- —^ -- —
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Cummulative Volume, cu. ft.
12/12/201211:36 AM D:IProyectsl875-OO11DrainagelDetentionl875-001—Detention Pond.x1smlStage_Storage_2nd PDP
W INORTHERN
ENGINEERING
West Range Fort Collins
Developed Condition Orifice PlateSnCalculations
eaeveop on lion e Year
Design Paint Sub -Basin A Orifice Calculation:
0, = CA(29H)o.5
Tailwater Elevation 4999.41
100-year WSEL 5001.40
Invert Out 4999.41
Allowable Release Rate 0.50 cfs
H 1.84 ft
C 0.65
g 322 ft/s
% 0.500 cts
Diameter 0.3000 It
A 0.07 ftz
A 10.18 in'
Diameter of WO Orifice: in
Diameter of 100-year Orifice: 3 in
2/19/2013 1:13 PM
I
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N orth ern En ain eerina.com 11 970.221.6158
(NORTHERN
ENGINEERING
West Range Fort Collins
9 Design Procedure Form: Rain Garden (RG) 11
Sheet 1 of 2
Designer: H. Felssner
Company:
Northern Engineering
Date:
December 12, 2012
Project:
West Range Fart Collins
Location:
Fort Collins, Colorado
1. Basin Storage Volume
A) Effective Imperviousness of Tributary Area, I,
I, =
830
(100% 8 all paved and roofed areas upstream of rain garden)
B) Tributary Area's Imperviousness Ratio (i = I/1GO)
i =
0.830
C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time
WQCV =
0.28 watershed inches
(WQCV= 0.8 • (0.91 • le. 1.19 - I° + 0.78 ` i)
D) Contributing Watershed Area (including min garden areal
Area =
19.886 sq It
E) Water Quality Capture Volume (WQCV) Design Volume
Vwov =
461 cu N
Val = (WQCV / 12) " Area
F) For Watersheds Outside of the Denver Region, Depth of
it, =
in
Average Runoff producing Storm
G) For Watersheds Outside of the Denver Region,
VWACN OTHER =
0.0 Cu it
Water Quality Capture Volume (WQCV) Design Volume
HI User Input of Water Quality Capture Volume (WQCV) Design Volume
Vwpw. user =
cu it
(Only R a different WQCV Design Volume is desired)
2. Basin Geometry
A) WQCV Depth (12-inch maximum)
Dwow =
11 in
8) Rain Garden Side Slopes (Z = 4 min., hoiz. dist per unit vertical)
Z =
0.00 It / N
Will "0" d rein garden has vertical walls)
C) Mimimum Flat Surface Area
ARE. =
309 sq it
D) Actual Flat Surface Area
Aauou -
90 sq IT ACTUAL FLAT AREA MINIMUM FLAT AREA
E) Area at Design Depth (Top Surface Area)
AT. =
520 sq ff
Fit Rain Gahm Total Volume
VT=
280 Cu N TOTAL VOLUME -- DESIGN VOLUME
(VT= ((Arno + Aem,n) / 2) • Depth)
3. Growing Media
Choose 0.
O 18" Rain Garden Growing Media
0 Omer (Expleln):
Fort Collins Soil Mix
60%Sand (ASTM C-33), 25% Topsoil and 15 % Shredded Mulch
4. Underdram System
A) Am undendrains provided?
Goose One
YFS
NO
B) Underdrain system writhe diameter for 12 hour drain time
1) Distance From Lowest Elevation of the Storage
y =
N/A It
Volume to the Center of the Orifice
i0 Volume to Drain in 12 Hours
Vol,, =
WA CUT N
ill) Orifice Diameter, 3/e" Minimum
Do =
NIA in
875-001_1.113-BMP_V3_01, RG
12112/2012, 12:26 PM
West Range Fort Collins
NORTHERN
ENGIn EERInG
Design Procedure Form: Rain Garden (RG)
Sheet 2 of 2
Dcelgncr- H. Feissner
Cmnpany: Northern Engineering
Dote: December 12, 2012
Project: West Range Fort Collins
Location: Fort Collins, Colorado
S. Impermeable Geemembane Liner and Geotextile Separator Fabric
a. One
O YES
A) Is an impermeable liner provided due to proximity
(9) NO
a1 structures or groundwater contamination?
6. Inlet / Outlet Centel
Choose Ore
rO 9xet Flow- No Emew Dissipatlon Required
A) Inlet Commit
I O Concentrated Row- E+ergy Dissipation Prowled
Choose One
7, Vegetation
O Seed (Plan for frequent weed control)
* Plantains
O Sand Grown or Other High Infiltration Sod
B. Irrigation
Choose one
O YES
A) Will the rain garden be irrigated?
O NO
Notes:
I
1
I
t
875-001_UD-BMP_0_01, RG 12J1212012. 12:26 PM
NORTHERN
ENGINEERING
ADDRESS: PHONE: 970.221.4158 WEBSITE:
200 S. College Ave. Suite 10 www,norThernengineering.com
Fort Collins, CO &0524 FAX: 970.221.4159
REFER TO THE LANDSCAPE
PLANS FOR PLANTING WITHIN
THE BIO-RETENTION AREA
LANDSCAPE
WALL VARIES
(SEE LANDSCAPE
FOR DETAILS) 8" BIO-RETENTION
SAND MEDIA
MIN. 6" PEA GRAVEL
MIN. 10" GRAVEL LAYER)
MEETING CDOT #4
COARSE AGGREGATE
SPECIFICATION.
NOTES:
1. REFER TO THE 810-RETENTION SAND MEDIA SPECIFICATION FOR MORE
INFORMATION ON THE SOIL MIX.
2. BIO-RETENTION SAND MEDIA SHALL BE PROVIDED BY HAGEMAN EARTH
CYCLE OR APPROVED EQUAL.
CAL B10-RETENTION SECTION
& GUTTER
FABRIC
■
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•
Nnrrhwrn Ennin eerin n.rom // 970.221.4158
BMP Maintenance
1
' 5.0 Bioretention (Rain Garden or Porous Landscape Detention)
The primary maintenance objective for bioretention, also known as porous landscape detention, is to keep
' vegetation healthy, remove sediment and trash, and ensure that the facility is draining properly. The
growing medium may need to be replaced eventually to maintain performance. This section summarizes
key maintenance considerations for bioretention.
' 5.1 Inspection
Inspect the infiltrating surface at least twice annually following precipitation events to determine if the
' bioretention area is providing acceptable infiltration. Bioretcntion facilities are designed with a maximum
depth for the WQCV of one foot and soils that will typically drain the WQCV over approximately 12
hours. If standing water persists for more than 24 hours after runoff has ceased, clogging should be
' further investigated and remedied. Additionally, check for erosion and repair as necessary.
5.2 Debris and Litter Removal
Remove debris and litter from the infiltrating surface to minimize clogging of the media. Remove debris
and litter from the overflow structure.
' 5.3 Mowing and Plant Care
All vegetation: Maintain healthy, weed -free vegetation. Weeds should be removed before they
flower. The frequency of weeding will depend on the planting scheme and cover. When the growing
media is covered with mulch or densely vegetated, less frequent weeding will be required.
• Grasses: When started from seed, allow time for germination and establishment of grass prior to
mowing. If mowing is required during this period for weed control, it should be accomplished with
hand-held string trimmers to minimize disturbance to the seedbed. After established, mow as desired
' or as needed for weed control. Following this period, mowing of native/drought tolerant grasses may
stop or be reduced to maintain a length of no less than 6 inches. Mowing of manicured grasses may
vary from as frequently as weekly during the summer, to no mowing during the winter. See Section
' 4.4 for additional guidance on mowing.
1
1
1
1
' November 2010 Urban Drainage and Flood Control District 6-7
Urban Stone Drainage Criteria Manual Volume 3
BMP Maintenance
5.4 Irrigation Scheduling and Maintenance
Adjust irrigation throughout the growing season to provide the proper irrigation application rate to
maintain healthy vegetation. Less irrigation is typically needed in early summer and fall, while more
irrigation is needed during the peak summer months. Native grasses and other drought tolerant plantings
should not typically require routine irrigation after establishment, except during prolonged dry periods.
Check for broken sprinkler heads and repair them, as needed. Completely drain the irrigation system
before the first winter freeze each year. Upon reactivation of the irrigation system in the spring, inspect
all components and replace damaged parts, as needed.
5.5 Replacement of Wood Mulch
Replace wood mulch only when needed to maintain a mulch depth of up to approximately 3 inches.
Excess mulch will reduce the volume available for storage.
5.6 Sediment Removal and Growing Media Replacement
If ponded water is observed in a bioretention cell more than 24 hours after the end of a runoff event,
check underdrain outfall locations and clean -outs for blockages. Maintenance activities to restore
infiltration capacity of bioretention facilities will vary with the degree and nature of the clogging. If
clogging is primarily related to sediment accumulation on the filter surface, infiltration may be improved
by removing excess accumulated sediment and scarifying the surface of the filter with a rake. If the
clogging is due to migration of sediments deeper into the pore spaces of the media, removal and
replacement of all or a portion of the media may be required. The frequency of media replacement will
depend on site -specific pollutant loading characteristics. Based on experience to date in the metro Denver
area, the required frequency of media replacement is not known. To date UDFCD is not aware of any
rain gardens constructed to the recommendations of these criteria that have required full replacement of
the growing media. Although surface clogging of the media is expected over time, established root
systems promote infiltration. This means that mature vegetation that covers the filter surface should
increase the life span of the growing media, serving to promote infiltration even as the media surface
clogs.
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6-8 Urban Drainage and Flood Control District November 2010
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' Landscape Maintenance S-9
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Description
Proper landscape maintenance, including
maintenance of vegetated stormwater
BMPs, is important to reduce nutrient
and chemical loading to the storm drain
system, reduce nuisance flows and
standing water in stormwater BMPs, and
maintain healthy vegetation that helps
minimize erosion. Additionally, when
landscapes and vegetated BMPs are over -
irrigated, the ground remains saturated
and capacity to infiltrate runoff is
reduced.
Appropriate Uses
Appropriate lawn care practices are
applicable to residential, commercial,
municipal, and some industrial operations.
Practice Guidelines'
Photograph LM-1. Over -irrigation and overspray can wash fertilizers
and lawn chemicals into the storm drain system. These flows can
comingle with storm runoff and cause nuisance flow conditions in
stormwater BMPs. Photo courtesy of the City of Westminster.
Practice guidelines for a healthy lawn that reduces pollution during both wet and dry weather conditions
include a combination of practices such as mowing, aeration, fertilization, and irrigation. Also, see the
Pesticide, Herbicide, and Fertilizer Usage BMP for information on proper use of these chemicals and
Integrated Pest Management (IPM) strategies.
Lawn Mowing and Grass Clipping Waste Disposal
• Keep lawn clippings and debris out of gutters. When blowing walkways or mowing lawns, direct
equipment so that the clippings blow back onto the lawn rather than into the street, or collect
clippings blown onto the street and properly dispose of them.
Mulch -mowing turfgrass at a height of 2.5 to 3 inches helps turfgrass develop deeper root systems.
No more than one-third of the grass blade should be removed in a single mowing. Mulched grass
clippings can return roughly 25 to 30% of the needed nitrogen that grass requires to be healthy,
thereby reducing fertilizer requirements. Avoid throwing grass clippings onto streets and sidewalks
to reduce nutrient pollution to surface waterbodies.
• Minimize thatch development by mowing at appropriate frequencies and heights for the grass type,
avoiding overwatering, preventing over fertilization, and aerating the turf.
These practice guidelines have been adapted from the GreenCO Best Management Practices for the
Conservation and Protection of Water Quality in Colorado: Moving Toward Sustainability (GreenCO
and WWE 2008). See this manual for additional detail and references.
' November 2010 Urban Drainage and Flood Control District LM-1
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S-9 Landscape Maintenance
Lawn Aeration
Aerate turf once or twice per year, as needed, in the early spring and/or late fall to aid in capturing the
natural precipitation during non -weed germination periods and prior to adding organic materials and
fertilizers. Aeration reduces soil compaction and helps control thatch in lawns while helping water
and fertilizer move into the root zone.
A lawn can be aerated at any time the ground is not frozen, but should not be done when it is
extremely hot and dry. Heavy traffic areas will require aeration more frequently.
Do not use spike -type aerators, which compact the
soil. Holes should be two to three inches deep and
no more than two to four inches apart. Lawns
should be thoroughly watered the day before
aerating so plugs can be pulled more deeply and
easily. Mark all sprinkler heads, shallow irrigation
lines, and buried cable TV lines before aerating so
those lines will not be damaged.
Fertilizer Application
Phosphorus
Phosphorus is commonly overused
and application should be based on
soil tests. Phosphorus washing into
surface waterbodies leads to
excessive algae growth.
• Apply fertilizer when needed to achieve a clearly Phosphorous does not move out of
defined objective such as increasing shoot growth, the soil like nitrogen, so constant
root growth, flowering or fruiting; enhancing additions are unnecessary.
foliage color, and plant appearance; or correcting
or preventing nutrient deficiencies.
• Because manufactured fertilizers can be relatively
high in nutrient content, it is critical to follow the
manufacturer's directions, using the minimum
amount recommended. Over -application "burns"
leaves and may lead to water pollution, thatch buildup, excessive mowing, and weed growth.
• Only apply nutrients the plants can use. Fertilizer labels identify product contents in terms of ratios
that indicate percentage of ingredients by product weight.
Soil Testing
There are several qualified laboratories in Colorado that provide soils tests to determine
recommendations for fertilizer type and application rates. There are also commercially available
quick test kits that are less accurate but could be used by a homeowner. Without an analysis, a
homeowner may be buying unnecessary fertilizer or applying too much. A $20 to $40 soil analysis
has potential to save an owner much more.
The CSU Extension program offers a soil testing service. Contact the CSU Extension for your
county or visit http://www.ext.colostate.edu for more information including a list of laboratories.
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Landscape Maintenance S-9
When practical and appropriate, base fertilizer application on soil analysis. Be aware that at many
new development sites, soil conditions following grading often no longer consist of topsoil.
"Basement" soils with poor texture and low nutrient content may be present. As a result, soil
amendment is often needed to improve the physical properties (tilth) of the soil to provide a better
environment for plant roots to improve nutrient uptake. Soil analysis can help to identify soil
amendments that improve both the physical and nutrient characteristics of the soil, as well as identify
fertilization requirements.
Utilize split applications of slow -release (controlled -release) fertilizer forms such as IBDU, sulfur -
coated urea and natural organic -based fertilizers (not to be confused with raw manure) to minimize
the risk of nutrients leaching into groundwater or running off in surface water. When properly
applied, other forms of fertilizer can also be safely used, provided that over -watering and over -
fertilization do not occur.
When applying fertilizer, broadcast it uniformly over the targeted area of the landscape. Keep
fertilizer off streets, sidewalks, and driveways to prevent water pollution. Fertilizer that inadvertently
falls on impervious surfaces should be swept back onto the lawn.
Recommendations for fertilizer application vary among industry professionals. CSU Extension's
fertilizer recommendations for established Colorado lawns are provided in the table below. Site -
specific conditions should also be considered when determining the need for fertilizer.
Table LM-1. CSU Extension Recommendations for
Nitrogen Application Rate
Nitro en Appfification Rate in Pounds/1,000 s . ft.
Mid -March to
May to Mid -
July to
Mid -August to
Early October to
Turfgrass Species
April A a
June n
Early
B
Mid-
Early November'
n
August
September'"
High Maintenance
0.5-1
1
Not
1
1-2 (optional)
Bluegrass R e ass
Required
Low Maintenance
0.5
0.5-1
Not
I
1 (optional)
Bluegrass
Required
Tall Fescue
0.5
0.5-1
1
1 (optional)
Required
Fine Fescue
0.5
0.5-1
ot
0.5-1
None
Required
Buffalo grass, Blue
Grama, Bermuda
None
0.5-1
0.�;-I
None
None
ass
Notes:
"The March -April nitrogen application may not be needed if prior fall fertilization was completed. If spring green -
up and growth is satisfactory, delay fertilizing to May or June.
B Application rates may be reduced by 1/4 to 1/3 when grass clippings are left on the lawn.
c On very sandy soils do not fertilize turf after late September to prevent nitrogen from leaching into groundwater
during the winter months.
"Apply when the grass is still green and at least 2-3 weeks prior to the ground freezing. Optional nitrogen
applications are indicated for use where higher quality or heavily -used turf is present.
Source: T. Koski and V. Skinner, CSU Extension, 2003.
' November 2010 Urban Drainage and Flood Control District LM-3
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S-9 Landscape Maintenance
• If possible, properly irrigate turf following fertilization to help grass utilize applied nutrients and to
minimize the potential for fertilizer burn. Care should be taken to avoid excessive irrigation that
would result in fertilizer being washed away. Similarly, avoid application of fertilizer immediately
prior to heavy rainfall.
• Fall is the best time of year to fertilize bluegrass lawns. Over -application of nitrogen fertilizer in
April may cause grass to grow too fast before roots can support the growth, resulting in less heat
tolerance.
• Generally, the Colorado Nursery and Greenhouse Association recommends waiting until the second
growing season to fertilize ornamental (woody) plants. Commercial fertilizer should not be used in
the backfill where it comes in direct contact with the roots.
Maintain a buffer zone around wells or surface waterbodies where fertilizers are not applied to
minimize pollution. Consult the fertilizer product label and local regulations and landscape
ordinances for appropriate distances. Research in this area is limited; however, CSU Extension
recommends a buffer of 6 to 10 feet for mowed turf areas.
• In areas with sandy soils, it is particularly important to avoid over -application of fertilizer that could
leach into groundwater. These areas may be particularly well suited to slow -release fertilizer forms
and conservative application rates.
Lawn Irrigation
• The approximate amount of water that needs to be applied each week for an average, traditional lawn
to supplement normal rainfall is listed in Table 2. (Water utilities may provide additional guidance in
terms of suggested run-times for various sprinkler types; http:/iwww.denverwater.org/Conservation/.)
Table LM-2. General Guideline for Approximate Supplemental Water
for an Average Traditional Lawn (inches per week)
Condition`
Aril'
May
June
July
AugSet
Oce
Non -Drought
Conditions
I/4"
I"
1'/"
I'/-"
1'/."
1"
1/2"
During Drought
Restrictions (approx.
20%reduction)
1/4"
4"
I''/a"
IW,
1"
3/4"
I/2"
'For established lawns, water may not be required during April. Base decision on weather conditions.
a For established lawns, water is typically not required after Oct 15.
3Under less -than -average rainfall conditions, the amounts shown in the chart should be increased. If
there is greater -than -normal rainfall, then the amount of supplemental water should be reduced.
Consult with the CSU Extension Turfgrass program for recommendations for irrigating turfgrasses
with lower water requirements (e.g. blue grams, buffalo grass). For native grasses, irrigation may be
unnecessary or limited to certain conditions.
hrigate the lawn uniformly until the soil is moist to a depth of 4 to 6 inches to encourage deep roots.
Frequent, light sprinklings moisten only the surface and may cause shallow -rooted turf and increase
weed seed germination. Properly maintain the irrigation system to ensure that the irrigation is being
applied at appropriate rates and to the turfgrass, not the sidewalk.
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Landscape Maintenance S-9
• Maintain irrigation systems in good operating condition with uniform distribution of water. "Smart"
irrigation controllers and weather sensors can reduce water waste by shutting off irrigation during
storm events and helping owners water according to the needs of the plants to replace water lost to
evapotranspiration (ET).
• Proper irrigation can minimize the amount of fertilizer and other chemicals that are leached below the
root zone of the grass or washed away by runoff.
' November 2010 Urban Drainage and Flood Control District LM-5
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Use of Pesticides, Herbicides and Fertilizers S-8 ,
Description
Pesticides, herbicides, fertilizers, fuel and
other landscape maintenance chemicals
must be properly applied, stored, handled
and disposed of to prevent contamination
of surface water and groundwater. Misuse
of pesticides and herbicides can result in
adverse impacts to aquatic life, even at low
concentrations. Misuse of fertilizer can
result in increased algae growth in
waterbodies due to excessive phosphorus
and nitrogen loading.
Appropriate Uses
Photograph PHF-I. Pesticide, fertilizer, and herbicide applications
should be applied in the minimum quantities necessary to achieve
This BMP applies to both commercial and
specific landscaping objectives, while keeping chemicals out of storm
drain systems. Photo courtesv of W WE.
municipal landscaping operations, as well as
to homeowners and homeowner associations.
For commercial operations, the scale of chemical usage and
handling is greater; therefore, additional measures are often required under federal and state law.
Practice Guidelines'
Public education regarding appropriate landscape chemical application and handling is an important
action that local governments can take to reduce the likelihood that landscape chemicals are washed into
storm drains and receiving waters through runoff. Local governments can make landscape care
information available on websites, in utility mailers, lawn care centers, and other locations. A variety of
professional organizations for lawn care professionals already exist and can be contacted for additional
information or partnered with for both public education and landscape professional educational efforts
and certification programs (See www.ext.colostate.edu and www.creenco.or¢.).
General Guidelines for Pesticide, Herbicide, and Fertilizer Application
Apply fertilizers, pesticides, and other chemicals according to manufacturer's directions. The label is
the law for pesticide usage. Apply pesticides and herbicides only when needed and use in a manner
to minimize off -target effects. See the Landscape Management Fact Sheet for fertilizer application
guidelines.
Accurately diagnose the pest. Disease and insect symptoms can mimic each other in many plants. A
fungicide will not control an insect, and an insecticide will not control a disease.
• Be aware that commercial chemical applicators must receive thorough training, licensure and proper
certification prior to chemical use. Consult Colorado Department of Agriculture (CDA) Regulations
for specific requirements.
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t These practice guidelines have been adapted from the GreenCO Best Management Practices for the
Conservation and Protection of Water Quality in Colorado: Moving Toward Sustainability (GreenCO '
and W WE 2008). See that manual for additional detail and references.
November 2010 Urban Drainage and Flood Control District PHF-1 ,
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' S-8 Use of Pesticides, Herbicides and Fertilizers
' Know characteristics of the application site, including soil type and depth to groundwater to avoid
migration of chemicals into groundwater.
Select pesticides and herbicides best suited to the characteristics of the target site and the particular
' pest or weed. Half-life, solubility, and adsorption should be compared to site characteristics to
determine the safest chemical. Choose least toxic and less persistent sprays whenever possible based
on comparison of labels and associated material safety data sheets.
• Employ application techniques that increase efficiency and allow the lowest effective application rate.
Carefully calibrate application equipment and follow all label instructions.
' • Recognize that it is not realistic for a landscape to be completely pest -free or weed -free. Consider
using Integrated Pest Management (IPM) strategies to minimize chemical usage.
' ■ Keep pesticide and fertilizer equipment properly calibrated according to the manufacturer's
instructions and in good repair. Recalibrate equipment periodically to compensate for wear in pumps,
nozzles and metering systems. Calibrate sprayers when new nozzles are installed.
• All mixing and loading operations must occur on an impervious surface.
Integrated Pest Management (IPM)
' Integrated pest management (IPM) (also known as Plant Health Care) is the practice of using targeted
biological, chemical, cultural, and physical measures to manage pests while minimizing or eliminating
the use of chemical pesticides. IPM measures benefit the landscape and help reduce the likelihood that
lawn chemicals will be washed into storm drainage systems in stormwater runoff. The pros and cons of
various tools should be weighed and used in an integrated manner to achieve pest control objectives in
' a safe, effective, and cost-effective manner. Basic IPM practices that can be adopted include:
Consider spot treatments of pests rather than treating the entire area.
' • Consider pest occurrence and history when developing pest management strategies.
■ Time pesticide application to minimize host plant damage and maximize pest control.
' • Rotate annual garden plants to reduce the buildup of soil -borne pests. Clean up plant litter and
remove weeds before they go to seed. Remove infested plant residue from the garden in the fall so
' that pests do not over -winter there.
• Implement cultural controls such as proper plant selection, planting time, and planting method to
reduce susceptibility to insects, pests, and diseases, thereby reducing pesticide usage.
' • Implement mechanical and physical controls where practical as an alternative to chemical
application. Examples include a wide variety of practices such as "collars" around seedlings,
mulching, solar heating, syringing, handpicking, mowing, hoeing, and traps.
Use biological controls where appropriate to reduce pesticide usage. For example, introduce
' natural enemies of pests such as lady beetles and green lacewings. (Note: pesticides may kill these
natural enemies.)
Consider applying environmentally friendly chemical alternatives such as insecticidal soaps,
' horticultural oils, and other such measures when practical and effective and when mechanical
approaches are impractical.
' 11I1 F-? Urban Drainage and Flood Control District Nm ember 3010
Urban Storm Drainage Criteria Manual Volume 3
Use of Pesticides, Herbicides and Fertilizers
Application Practices
• Keep records of pesticide application and provide signage as required by law.
1
S_8 ,
• Do not apply pesticides or herbicides during high temperatures, windy conditions or immediately
prior to heavy rainfall or irrigation.
• Treat for and control noxious weeds prior to installing the landscape using an herbicide targeted to the
weeds that are present and applied in accordance with the product label.
• Be aware that some pesticide formulations are not compatible with other pesticides and combining
them may result in increased potency and phytotoxicity.
Managing Mosquitoes in Stormwater Facilities
(Adapted from: Peairs and Cranshaw 2007)
The key to mosquito control is larval management. Larvae occur in specific areas and can be
controlled by modifying the habitat through drainage or insecticides applied to larval breeding sites.
Weekly mosquito inspections at stormwater facilities with targeted treatments are frequently less costly
and more effective than regular widespread application of insecticides. These inspections can be
performed by a mosquito control source and typically start in mid -May and extend to mid -September.
Mosquito control measures must be cost effective and environmentally sound. Consider alternatives
before application of conventional chemical insecticides.
• Habitat Modification: Eliminating breeding sites, or habitat modification, is an effective and
long-term solution. Proper maintenance of stormwater BMPs to avoid shallow standing water is
important.
Natural Predators: Fish, dragonfly nymphs, and diving beetles are natural predators of mosquito
larvae; dragonflies, birds, and bats feed on adults. Consult the Colorado Division of Wildlife for
recommendations, restrictions and regulations regarding mosquito -eating fish.
• Insecticides: Microbial insecticides such as the bacteria "Bti" (Bacillus thuringiensis israefiensis)
can be as effective as chemical insecticides. Bti is toxic only to mosquito and midge larvae. It is
not hazardous to non -target organisms but can reduce midge populations that serve as fish food.
"Soft" chemical insecticides, such as the insect growth regulator methoprenc, are toxic only to
insects and other arthropods. They are similar to certain insect hormones and create imbalances in
the levels of hormones needed for proper mosquito growth and development. They do not directly
harm fish or other wildlife but can reduce the amount of available food.
Mosquito larvae also can be controlled by the application of larvicidal oils or chemical
insecticides to the water where they occur or are suspected to occur. Remember, several
alternatives to conventional chemical larvicides have been developed because of concerns about
applying chemicals to water that might be used for drinking or that contains fish and other aquatic
life.
If larval control fails, adult mosquito control may be necessary. Adult control generally is done with
insecticide applications using ground equipment or aircraft. For more information visit:
www.ext.colostate.edu/westae/mosquito mgt.hunl or www.ext.colostate.edu/westtiile/fae.htm].
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S-8 Use of Pesticides, Herbicides and Fertilizers
• Maintain a buffer zone around wells or surface water where pesticides are not applied. Consult local
regulations and landscape ordinances, as well as the product label, for distances, which may vary
depending on the type of chemical and the sensitivity of the waterbody. The purpose of this practice
is to keep pesticides and herbicides out of surface waterbodies.
Storage Practices
' Storage areas should be secure and covered, preventing exposure to rain and unauthorized access.
Commercial and municipal facilities should provide basic safety equipment such as fire extinguishers,
warning signs (e.g., "no smoking"), adequate light and ventilation, and spill clean-up materials should
' be present. Floors and shelves should be non -porous (e.g., metal, concrete) to prevent sorption of
chemicals. If possible, temperature control should be provided to avoid excessive heat or cold.
Storage areas should be kept clear of combustible material and debris.
' Commercial operations handling large quantities of pesticides and fertilizers should consult the
Colorado Department of Agriculture for storage and handling requirements. Commercial greenhouses
and nurseries that are storing recycled water laden with fertilizer may need to provide secondary
containment to contain the water in the event of a tank rupture or leak.
Store chemicals in their original containers, tightly closed, with labels intact. Also inspect them
' regularly for leaks. Store nitrate -based and other oxidizing fertilizers separately from solvents, fuels,
and pesticides to reduce fire risk. Follow the general principle of storing like chemicals together.
Dry chemicals should be stored above liquids and on pallets to ensure that they do not get wet.
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Locate chemical storage and maintenance areas, as well as vehicle refueling and maintenance areas,
away from wells and surface waterbodies in accordance with local regulations, typically at least 50 to
100 feet away.
Figure PHF-1. Example Combined Pesticide and Fertilizer Storage and Mixing Area. Figure courtesy of
Designing Facilities,%r Pesticides and Fertilker Containment, Midwest Planning Service, Agricultural
Engineering, Iowa State University 1991.
PHF4 Urban Drainage and Flood Control District November 2010
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Use of Pesticides, Herbicides and Fertilizers S-8
Make available all Material Safety Data Sheets (MSDSs) in a readily accessible area. A list of all
hazardous chemicals in the work place must be completed to ensure that all MSDSs are readily
available.
Do not store large quantities of pesticides for long periods of time. Adopt the "first in, first out"
principle, using the oldest products first to ensure that the shelf life does not expire. Buy smaller
quantities of pesticides and fertilizers, thereby reducing storage issues.
Spills and Disposal
Never pour lawn and garden chemicals or rinse water down storm drains (or sanitary drains) and keep
chemicals off impervious surfaces (e.g., streets, gutters) during application.
Follow label directions for disposal. This typically involves triple -rinsing empty containers,
puncturing and crushing. All visible chemicals should be cleaned from the container prior to
disposal. Use local recycling or hazardous waste collection centers to dispose of unused chemicals.
• Properly manage chemical spills by cleaning them up as soon as possible, controlling actively spilling
or leaking materials, containing the spilled material (e.g., with absorbents, sand), collecting the spilled
material, storing or disposing of the spilled material, and following relevant spill reporting
requirements. "Washing down" a spill with water is not an appropriate cleanup approach.
Commercial operations should be aware of and comply with basic spill reporting requirements
required by law, and keep chemical spill cleanup equipment, personal protective equipment and
emergency phone numbers available when handling chemicals and their containers.
For More Information on Legal Requirements
Many federal and state regulations address pesticide, herbicide, and other chemical usage. These
sources should be consulted for the most current legal requirements related to chemical handling,
storage, application, disposal, and reporting of chemical spills. Examples include the federal
Insecticide, Fungicide and Rodenticide Act (FIFRA), the Superfund Amendments and
Reauthorization Act (SARA), the Emergency Planning and Community -Right -to -Know Act
(EPCRA), and Occupational Safety and Health Administration (OSHA) requirements, particularly
the Hazard Communication Standard. Colorado -related regulations include the Colorado Pesticide
Applicator's Act, and the Colorado Water Quality Control Act (25-8-601 and 25-8-606), Senate Bill
90-126, and The Agricultural Chemicals and Groundwater Protection Act, which identifies special
requirements for facilities handling more than 3,000 pounds (or 500 gallons) of bulk -formulated
pesticides.
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November 2010 Urban Drainage and Flood Control District PHF-5 '
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' Snow and Ice Management S-10
'
Description
For obvious safety reasons, snow
removal in Colorado is important;
'
however, snow removal and
management practices can adversely
impact vegetation, soils, water quality,
'
and air quality. Snow removal
contractors and operators should be
'
knowledgeable of these potential
impacts and choose management
measures with the fewest adverse
impacts, while still protecting the public
tsafety,
health and welfare.
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Appropriate Uses Photograph SIM-1. Snow storage locations should be clearly
communicated to snow removal contractors and located where they can
drain to stormwater BMPs or landscaped areas. Photo courtesy of
Snow and ice management procedures wWE.
are relevant for homeowners, contractors,
business owners, and transportation departments.
Practice Guidelines
• Physical removal of snow and ice by shovels, snowplows, or snow blowers usually has the least water
quality and landscape impacts, provided that storage areas are not piled directly on landscape plants
or drained directly to receiving waters. Plan for snow storage locations that minimize water quality
and landscape impacts prior to winter.
• Ensure that equipment is calibrated to optimum levels according to manufacturer's instructions.
• Consider placing barriers in targeted site -specific locations (i.e., along streams or direct drainages) to
route deicing material away from waterbodies.
• Reduce plowing speed in sensitive areas to prevent exposure to deicing material.
• Designate snow storage areas in locations that enable runoff to be directed to stormwater BMPs for
treatment, when practicable.
• The use of deicing chemicals can have a severe impact on plants growing near roads and sidewalks.
This can become a water quality issue when plants die and erosion results. Many deicing chemicals
are salts and can adversely affect plants through either direct contact with foliage or through buildup
in the soil over time. Representative impacts include:
'These practice guidelines have been adapted from the GreenCO Best Management Practices for the
' Conservation and Protection of Water Quality in Colorado: Moving Toward Sustainability (GreenCO
and WWE 2008). See this manual for additional detail and references.
' November 2010 Urban Drainage and Flood Control District SIM-1
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5-10 Snow and Ice Management
o Direct contact often occurs when the deicing chemicals accumulate on the plants due to drift
during application, or when snow or ice containing the chemical is shoveled or blown onto nearby
plants. Because these chemicals are salts, direct contact with the foliage may result in burning
due to a rapid dehydration effect.
o Buildup of de-icing chemicals in the soil may have even more detrimental effects. Repeated
application over time (either during a particular winter season or over many seasons) may damage
plants by making their roots unable to take up water. Symptoms will include wilting even when
the soil is moist, leaf bum or needle tip burn, stunting or lack of vigor, and/or deficiency
symptoms for one or more plant nutrients. The structure of clay soils can be changed to the point
that they are unable to support plant life.
Deicing chemicals that are considered safer to use around plants include calcium magnesium acetate
(CMA) or calcium chloride. As with all chemicals used in the landscape, be sure to read and follow
label instructions and do not over apply.
The Colorado Department of Transportation (CDOT) has conducted multiple studies on deicing
chemicals. The SeaCrest Group (2001) studied three groups of deicers for CDOT that were chloride -
based, acetate -based, and sanding materials. The chloride -based deicers included magnesium
chloride (FreezGard Zero® with Shield LSO, Ice-StopTM Cl, CaliberTM M 1000, Ice BanTM M50),
calcium chloride (Liquidowg, Armor(&), and sodium chloride (road salt and Ice Slicer®). The
acetate -based deicers include Calcium Magnesium Acetate (CMAO), Potassium Acetate (CF70),
Sodium Acetate (NAACO), and CMAKTM (a mixture of CMA and Potassium Acetate). Table 1
contains a partial summary of the study findings.
• Highlights of the SeaCrest (2001) study regarding impacts associated with the three categories
include:
o The chloride -based deicers have been shown to have adverse effects on terrestrial vegetation.
Damage to vegetation from deicing salts has been reported to a distance of 100-650 feet.
However, there is a wide range of tolerance of different species of plants to the effects of
chlorides. The chloride ions in deicers increase the salinity of the soil near the roadways where
they are applied. The magnesium and calcium ions increase the stability and permeability of the
soil, whereas sodium ions decrease soil stability and permeability.
o The acetate -based deicers are organic and have different kinds of effects on the environment than
the chloride -based deicers. The acetate ions are broken down by soil microorganisms and may
result in oxygen depletion of the soil, which can impact vegetation; however, the acetate deicers
CMA and Potassium Acetate (CMAK) are not harmful to terrestrial vegetation at the
concentrations typically used on roadways. However, NAAC may potentially have an adverse
effect on vegetation because of the presence of the sodium ion, which decreases the stability and
permeability of the soil. The depletion of oxygen in the soil from the breakdown of the acetate
ion can have a negative effect on plant growth, but field evidence of this effect is limited.
o Sand is not a deicer, but is used for snow and ice control because it improves traction. Sand has a
negative effect on water quality as a result of the increased turbidity caused by the presence of
sand particles in water. Excessive quantities of sand can smother vegetation.
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SIM-2 Urban Drainage and Flood Control District November 2010 '
Urban Storm Drainage Criteria Manual Volume 3
' Snow and Ice Management S-10
' Table SIM-1. Potential Environmental Impacts of Various Deicers
(Source: The SeaCrest Group 2001)2
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Inhibited
a r+
Ice Ban+
Inhibited
Magnesium
Magnesium
Magnesium
Sodium
Calcium
CMA
Potassium
Deicer/
Chloride
Chloride
Chloride
Chloridel Ice
Chloride
(Solidl
CMAN
Acetate
NAAC
Parameter
(Liquid)
(Liquid)
(Liquid)
Slicer(Solid
(Liquid)
Liquid)
(Liquid)
(Liquid)
Solid
Sand
Trace metals,
Trace metals,
Trace
Trace
Trace
Trace metals
phosphorus,
phosphorus.
Trace metals
metals,
Trace
metals,
Trace metals
metals.
Trace metals
ammonia
ammonia,
ammonia,
metals
ammonia,
phosphorus
Chemicals
nitrates
nitrates.
nitrates.
Improves
Improves
Improves
structure,
structure,
Increases
Improves
Improves
Improves
Improves
Decreases
structure,
increases
increases
salinity;
structure,
structure;
structure:
structure:
stability;
Minimal effects
increases
salinity,
salinity,
decreases
increases
oxygen
oxygen
oxygen
oxygen
salinity
oxygen
oxygen
stability
salinity
depletion
depletion
depletion
depletion
Soil
idepletion
depletion
Increases
Increases
Increases
salinity;
salinity;
Increases
Increases
Oxygen
Oxygen
Oxygen
Increases
Water
selinity
oxygen
oxygen
salinity
salinity
depletion
depletion
depletion
turbidity
Quality
da letion
depletion
Minimal as
Minimal air
Minimal air
Some air
Minimal air
Minimal air
Minimal air
Minimal air
Some air
High air pollution
Air Quality
pollution
pollution
pollution
pollution
pollution
pollution
pollution
pollution
pollution
potential
Can cover
Relatively
Relatively low
Moderate
Relatively
Relatively
Relatively
Moderate
Moderate
Relatively
benlhic
Aquatic
low toxicity
toxicity
toxicity
low toxicity
low toxicity
low toxicity
toxicity
toxicity
low toxicity
organisms and
cause mortality
Organisms
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Chlorides
Chlorides
Chlorides
Chlorides
Chlorides
Minimal
Minimal
Minimal
Effects to
Can cover
damage
damage
damage
damage
damage
damage
damage to
damage to
damage damage to
vegetation and
Terrestrial
vegetation
vegetation
vegetation
vegetation
vegetation
vegetation
vegetation
not
cause mortality
Vegetation
determined
Does not
Attracts
Does not
Not
Not
Not expected
May attract
May cover
attract
Does not
Does not
wildlife
attract
expected to
expected to
to attract
wildlife
burrows of small
Terrestrial
wildlife
attract wildlife
attract wildlife
contributing
wildlife
attract
attract
wildlife
contributing
animals and
Animals
Note: Trace metals that may be present include arsenic, barium, cadmium, chromium, copper, lead, mercury,
selenium, and zinc. Soil comments related to structure refer to the affect on soil stability, which relates to erosion.
See http:,hvw-w.coloradodot.info/proerams/researclt/Ddfsi2001 /deicers.odf/view for more information.
• Where practicable, do not use deicers to melt snow or ice completely, but to make their removal
easier. Deicers melt down through the ice or snow to the hard surface, then spread out underneath.
This undercuts and loosens the snow so shoveling and plowing can be done. For this reason, it is
helpful to apply deicers prior to snow events in some cases.
• Research has shown that the shape of deicing particles affects the speed of their penetration through
ice. Uniformly shaped spherical pellets of about 1/16 inch to 3/16 inch penetrate ice faster and more
efficiently than other shapes.
' Try to avoid the use of rock salt since it is generally most damaging to plants, soils and concrete and
metal surfaces. In areas where deicing salts are unavoidable, select plants with higher salt tolerances.
1
' 2 The SeaCrest Group, 2001. Evaluation of Selected Deicers Based on a Review of the Literature, Report No. CDOT-DTD-
2001-15. Prepared for Colorado Department of Transportation Research Branch.
' November 2010 Urban Drainage and Flood Control District SIM-3
Urban Storm Drainage Criteria Manual Volume 3
S-10 Snow and Ice Management
Do not plow snow directly into streams or wetlands. Snow storage and disposal areas should be
located in an area where snowmelt can infiltrate into the ground, filter through a vegetated buffer or
be otherwise treated prior to reaching streams and wetlands. Provide adequate storage volume to trap
sediment left behind by melting snow and plan regular maintenance to remove accumulated sediment.
• In areas subject to heavy chemical deicing use, flushing the soil with water after the last freeze may
alleviate bum potential. Year-round proper plant care will also make plants more tolerant to salt
exposure. However, for the overall health of the landscape, the goal should be to reduce or minimize
the use of deicing chemicals where they are not necessary for safety reasons.
If an electric/mechanical snow melting device is used to dispose of removed snow (e.g., The Can
snow melter, Snow Dragon, etc.), the owner or operator must obtain the appropriate permit prior to
discharge. Snowmelt from melting machines is typically considered process wastewater.
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SIM-4 Urban Drainage and Flood Control District November 2010 '
Urban Storm Drainage Criteria Manual Volume 3
I
' Disposal of Household Waste S-3
Description GGec
' NO
Improperly disposed household wastes arc a source of stormwater QO7G
' pollution. These wastes can include household chemicals, pet
waste, yard waste, litter, automotive maintenance waste, and others. Q1! rM
These materials can be transported in stormwater when the z e
materials are dumped directly into the storm drains or when they a Q
' are spilled on impervious surfaces and washed into the storm sewer Q yJ yi
system. Household wastes can contribute solids, nutrients, oxygen
' demanding substances, toxic substances, and bacteria to receiving / • Pity V
waters. Improper disposal of household wastes on the ground Q
surface can also lead to groundwater contamination.
' Proper disposal of household waste is dependent on behavioral Photograph DHW-1. Placing storm
change, which can be encouraged through public education dram markers (or stenciling) ti storm
g g g P sewer inlets is a public education tool that
programs and local ordinances that prohibit improper disposal of can be used to educate citizens and
' household waste. Additionally, local governments can provide discourage improper disposal of
appropriate facilities for proper disposal of waste. household waste in storm drains. Photo
courtesy of Nonpoint Source Colorado.
' This Fact Sheet focuses primarily on household waste. See the Good Housekeeping Fact Sheet for
additional information on waste management at commercial and industrial sites.
tAppropriate Uses
Educational efforts related to proper disposal of household waste can be targeted to homeowners and
businesses through municipal programs, civic groups, and others. Local governments should consider
measures needed in the following general categories:
Household/Commercial Waste: Household waste includes materials discarded on the land surface
t or into the stormwater system from residential and commercial areas. Wastes from commercial
businesses are generated by stores, restaurants, hotels, offices, and other non -manufacturing activities.
Household waste disposal objectives include containing and properly disposing of refuse (garbage),
' reducing litter, and encouraging proper household toxic waste disposal through public education and
access to appropriate disposal facilities.
' - Litter: Most litter is biodegradable and can create an oxygen demand in water as it decomposes.
Examples of litter are paper products, used diapers, etc. Research by Keep America Beautiful, Inc.
(1990) has shown that people litter where litter has already accumulated. Also according to Keep
America Beautiful, Inc. (1987), pedestrians and motorists account for less than 25 percent of litter,
' with the other sources being household waste, commercial and industrial waste, haulage vehicles,
loading docks, and construction sites. Reduction of litter through proper disposal can reduce its
accumulation on the urban landscape and its eventual entry into the stormwater system.
' - Pet Waste: Pet waste deposited on the ground can be transported by the storm drainage system to
receiving waters or by overland flow into waterways. Fecal matter potentially contains pathogenic
' viruses and bacteria; it also creates an oxygen demand in water. The majority of improperly disposed
pet waste occurs in public areas, such as streets and parks. Pet waste ordinances are common in
municipalities; however, these are difficult to enforce, especially with limited municipal resources.
' Education can help bring this problem to the public's attention, and can thereby reduce deposition of
pet waste on urban surfaces.
November 2010 Urban Drainage and Flood Control District DHW-1
Urban Storm Drainage Criteria Manual Volume 3
I
S-3 Disposal of Household Waste t
• Yard Waste: Yard waste includes limbs,
leaves and grass clippings that can
contribute nutrients, lawn chemicals, and
oxygen demand to receiving waters when
washed into storm sewers and waterways.
Public education efforts on the benefits of
composting and on proper disposal of yard
waste can help to reduce the volume of
yard waste entering the stormwater system
and receiving waters. Most yard waste
can be reused following composting, with
the exception of weeds and diseased plant
materials.
Used Oil and Automotive Fluids: Used
oil and automotive fluids including
antifreeze, brake fluid, transmission fluid,
grease, other lubricants, and petroleum -
based cleaning solvents are wastes
generated during automobile maintenance
by residential households and commercial
businesses. These can enter the storm
Composting
Composting is a natural method for
recycling organics such as yard trimmings
and food scraps, which comprise nearly a
quarter of municipal solids waste generated
(Keep America Beautiful 2010). Nearly
half of all U.S. states now ban yard waste
from landfills because it represents such a
large volume that can be productively
composted. Composted yard waste used as
mulch or soil amendment can provide
landscape water conservation benefits,
reduce the burden on landfills and is
protective of water quality.
drainage system if poured directly into
storm inlets or from residual on concrete or asphalt exposed to precipitation. Improper disposal of
used oil and automotive fluids causes receiving waters to become contaminated with hydrocarbons
and residual metals that can be toxic to stream organisms. Used oil and other petroleum products can
be recycled and are accepted by many auto parts stores and repair shops. Public education on the
location of these centers, the benefits of recycling, prevention of fluid leaks, and the importance of
proper disposal for improving stormwater quality can reduce the amounts of oil and used automotive
fluids reaching receiving waters.
Toxic Wastes: Toxic wastes are generated in small quantities by residential households and
commercial businesses. Examples include paint, solvents, putties, cleaners, waxes, polishes, oil
products, aerosols, acids, caustics, pesticides, herbicides, and certain medicines or cosmetics. These
products and their containers should always be disposed of in accordance with the product label or
recycled, if appropriate. When such toxic substances are improperly disposed of by dumping on
impervious surfaces or into street gutters or storm inlets, stormwater can transport these materials to
receiving waters.
Municipal Recycling Programs
Many communities throughout the country have implemented municipal recycling programs, rather
than relying on citizens to research and seek out recycling opportunities on their own. Curbside
recycling programs and municipal education campaigns can improve the success of recycling
programs. For more information on implementing a municipal recycling program, visit a variety of
U.S. Environmental Protection Agency websites such as:
http://www.eya.eov/epawaste/conserve/nT/index.htm and
http://www.ci)a,gov/region4/waste/rcra/mgLoolkit/index.html or review well developed local programs
such as Denver Recycles. i
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DHW-2 Urban Drainage and Flood Control District November 2010 '
Urban Storn Drainage Criteria Manual Volume 3
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Disposal of Household Waste S-3
Practice Guidelines
To reduce improper disposal of household waste, implement
public education efforts regarding how improper disposal of
wastes can degrade the quality of streams, rivers, lakes, and
wetlands. Local governments have many public education
options that can tailored to fit local needs and budget
constraints the best. Within local governments, opportunities for
KEEP
coordinated efforts among multiple departments may be
beneficial. For example, properly composting of yard waste can
IT C LEA N
provide a stormwater benefit when these materials are kept out of
the gutter, as well as a water conservation benefit when the
materials are reused as mulch and a solid waste management
benefit when these materials are kept out of landfills. Similarly,
public works and parks and recreation departments both benefit
from efforts related to pet waste disposal signage as well as
disposal facilities in parks.
Representative public education strategies may include
• Development, publication, and distribution of brochures.
'Cause WE'RE ALL
• Utility bill inserts, flyers, and handbills.
D OW N STR EA M
• Newspaper articles and/or advertisements.
STORM DRAINS LEAD To CREEKS!
• Development and distribution of educational videos.
• Public workshops, field demonstrations, or presentations to
KEEP IT CLEAN TIPS
targeted civic organizations, youth organizations, etc.
�r up after pet s put •a'u'n trash
iheck for leaks E reryde mover oil.
• Developing and offering school curricula or assembly
Use fertilizer spannoy.
programs.
, ep wirt s oil as of swim *am
Nasty or at a commerrvl carwash.
■ Creating posters, signs, and graphics for installation at parks,
school hallways, trails, etc.
• Storm drain stenciling to discourage dumping of materials into
Photograph DH W-2. Check with state
storm drains.
and local water quality agencies for public
education materials such as this door
• Signs, including graphics, on dumpsters and other locations
hanger developed by the Keep It Clean
encouraging proper waste disposal.
Partnership that can be adopted for use in
your community. Photo courtesy of
• Signs in parks and along streets on pet waste control and
Nonpoint Source Colorado.
ordinances.
Brochures and utility bill inserts on separation of wastes and recycling.
• Advertising the locations of existing toxic disposal sites and waste recycling centers.
Advertising the locations of existing automobile fluids and used oil disposal sites.
' November 2010 Urban Drainage and Flood Control District DHW-3
Urban Storm Drainage Criteria Manual Volume 3
I
S-3
Disposal of Household Waste
• Developing campaigns promoting voluntary neighborhood clean-up efforts.
• Advertisements or notices of private locations accepting yard waste for composting.
• Information on backyard or neighborhood composting and proper disposal of yard waste.
In addition to public education efforts, local governments can provide facilities that provide readily
available proper disposal opportunities. These practices include:
• Establishing and maintaining household toxics disposal sites.
• Annual or curbside collection of household toxics.
• Pet waste disposal bags in public parks.
• Providing waste containers in problem litter areas.
• Requiring waste -haulage truck covers.
• Seasonal or on -going collection programs for grass clippings, tree branches, and leaves with disposal
at composting or chipping facilities, paired with distribution programs for reuse of composted or
chipped materials.
With regard to household toxics, local governments should be aware that collection and disposal of
household wastes is expensive. Such programs require adequate training of operators, analysis of
unknown materials, safe transport and containers, extensive recordkeeping and awareness of regulatory
requirements (e.g., the federal Resource Conservation and Recovery Act) regarding disposal of such
materials.
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DHW4 Urban Drainage and Flood Control District November 2010 '
Urban Storm Drainage Criteria Manual Volume 3
' Good Housekeeping S-5
'
Description
Good housekeeping practices are designed
to maintain a clean and orderly work
'
environment. The most effective first
steps towards preventing pollution in
stormwater from work sites simply
'
involve using common sense to improve
the facility's basic housekeeping methods.
'
Poor housekeeping practices result in
increased waste and potential for
stormwater contamination.
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A clean and orderly work site reduces the
possibility of accidental spills caused by
mishandling of chemicals and equipment
and should reduce safety hazards to
personnel. A well -maintained material and
chemical storage area will reduce the
possibility of stormwater mixing with pollutants.
Photograph GH-1. Use dry clean-up methods to remove spilled
materials. Photo courtesy of Colorado Nonpoint Source Program.
Some simple procedures a facility can use to promote good housekeeping include improved operation and
maintenance of machinery and processes, material storage practices, material inventory controls, routine
and regular clean-up schedules, maintaining well organized work areas, signage, and educational
programs for employees and the general public about all of these practices.
Appropriate Uses
Good housekeeping practices require education and training, typically targeted to industries and
businesses, municipal employees, as well as the general public.
Practice Guidelines
Good housekeeping practices include these general areas:
• Operation and Maintenance
• Material Storage
• Material Inventory
• Training and Participation.
Operation and Maintenance
Consider implementing the following practices:
• Maintain dry and clean floors and ground surfaces by using brooms, shovels, vacuums or cleaning
machines, rather than wet clean-up methods.
• Regularly collect and dispose of garbage and waste material.
' November 2010 Urban Drainage and Flood Control District GH-1
Urban Storm Drainage Criteria Manual Volume 3
S-5 Good Housekeeping
Routinely inspect equipment to ensure that it is functioning properly without leaking and conduct
preventative maintenance and needed repairs.
• Train employees on proper clean up and spill response procedures.
Designate separate areas of the site for auto parking, vehicle refueling and routine maintenance.
• Promptly clean up leaks, drips and other spills.
• Cover and maintain dumpsters and waste receptacles. Add additional dumpsters or increase
frequency of waste collection if overflowing conditions reoccur.
• Where outdoor painting and sanding occur, implement these practices:
Conduct these activities in designated areas that provide adequate protection to prevent overspray
and uncontrolled emissions. All operations should be conducted on paved surfaces to facilitate
cleanup.
o Use portable containment as necessary for outside operations.
o Clean up and properly dispose of excess paint, paint chips, protective coatings, grit waste, etc.
Maintain vegetation on facility grounds in a manner that minimizes erosion. Follow the Landscape
Maintenance and Pesticide, Herbicide and Fertilizer Usage BMPs to ensure that minimum amounts of
chemicals needed for healthy vegetation arc applied in a manner that minimizes transport of these
materials in runoff.
Material Storage Practices
Proper storage techniques include the following:
• Provide adequate aisle space to facilitate material transfer and ease of access for inspection.
• Store containers, drums, and bags away from direct traffic routes to reduce container damage
resulting in accidental spills.
• Stack containers according to manufacturer's instructions to avoid damaging the containers from
improper weight distribution. Also store materials in accordance with directions in Material Safety
Data Sheets (MSDSs).
• Store containers on pallets or similar devices to prevent corrosion of containers that results from
containers coming in contact with moisture on the ground.
• Store toxic or hazardous liquids within curbed areas or secondary containers.
Material Inventory Practices
An up-to-date materials inventory can keep material costs down by preventing overstocking, track how
materials are stored and handled onsite, and identify which materials and activities pose the most risk to
the environment. Assign responsibility of hazardous material inventory to individuals trained to handle
such materials. A material inventory should include these steps:
• Identify all chemical substances present at work site. Perform a walk-through of the site, review
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GH-2 Urban Drainage and Flood Control District November 2010 ,
Urban Storm Drainage Criteria Manual Volume 3
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Good Housekeeping S-5
purchase orders, list all chemical substances used and obtain Material Safety Data Sheets (MSDS) for
all chemicals.
Label all containers. Labels should provide name and type of substance, stock number, expiration
date, health hazards, handling suggestions, and first aid information. Much of, this information can
be found on an MSDS.
• Clearly identify special handling, storage, use and disposal considerations for hazardous materials on
the material inventory.
• Institute a shelf -life program to improve material tracking and inventory that can reduce the amount
of materials that are overstocked and ensure proper disposal of expired materials. Careful tracking of
materials ordered can result in more efficient materials use. Decisions on the amounts of hazardous
materials that are stored on site should include an evaluation of any emergency control systems that
are in place. All storage areas for hazardous materials should be designed to contain spills.
Training and Participation
Frequent and proper training in good housekeeping techniques reduces the likelihood that chemicals or
equipment will be mishandled. To promote good housekeeping, consider implementing these practices:
• Discuss good housekeeping practices in training programs and meetings.
• Publicize pollution prevention concepts through posters or signs.
• Post bulletin boards with updated good housekeeping procedures, tips and reminders.
' November 2010 Urban Drainage and Flood Control District GH-3
Urban Storm Drainage Criteria Manual Volume 3
C4.00 — Drainage Exhibit (West Range Fort Collins I Northern Engineering)
1 of 2 — Phase 1 Grading, Drainage and Erosion Control Plan (Shear Engineering)
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