HomeMy WebLinkAboutDrainage Reports - 04/07/2014City of Ft. Collins Ap rove Plans
Approved By
Date — J
FINAL DRAINAGE AND EROSION
CONTROL REPORT FOR
CARGILL OFFICE EXPANSION
Prepared for:
Steve Stadelmaier
Cargill
2540 East Drake Road
Fort Collins, CO 80525
Prepared by:
North Star Design
700 Automation Drive, Unit I
Windsor, Colorado 80550
(970)686-6939
December 18, 2013
Job Number 339-02
North Star
eaw design
700 Automation Drive, Unit I
Windsor, CO 80550
Phone:970-686-6939
Fax:970-686-1188
December 18, 2013
Glen Schlueter
City of Fort Collins Stormwater
700 Wood Street
Fort Collins, CO 80522
RE: Final Drainage and Erosion Control Report for Cargill Office Expansion
Dear Glen,
I am pleased to submit for your review and approval, this Final Drainage and Erosion Control
Report for Cargill Office Expansion. I certify that this update for the drainage design of the
Cargill Greenhouse was prepared in accordance with the criteria in the City of Fort Collins
Storm Drainage Manual.
I appreciate your time and consideration in reviewing this submittal. Please call if you have any
questions.
Prepared by:
Patricia Kroetch P.E.
Project Manager
`tl.... IIN"
TABLE OF CONTENTS
TABLE OF CONTENTS ............................................................................................................... ni
GENERAL LOCATION AND DESCRIPTION
1.1 Location...................................................................................................................1
1.2 Description of Property............................................................................................1
1.3 Major Basin Description..........................................................................................1
1.4 Sub Basin Description..............................................................................................I
2. DRAINAGE DESIGN CRITERIA
2.1 Regulations..............................................................................................................1
2.2 Development Criteria Reference and Constraints....................................................2
2.3 Hydrologic Criteria..................................................................................................2
2.4 Hydraulic Criteria....................................................................................................2
3. DRAINAGE FACILITY DESIGN
3.1 General Concept.......................................................................................................2
3.2 Specific Flow Routing.............................................................................................3
3.3 Drainage Summary..................................................................................................3
4. STORMWATER MANAGEMENT CONTROLS .
4.1 SWMP contact information.....................................................................................3
4.2 Identification and location of all potential pollution sources...................................4
4.3 Best Management Practices (BMP's) for Stormwater Pollution Prevention ........... 5
4.4 BMP Implementation...............................................................................................7
5. CONCLUSIONS
5.1 Compliance with Standards..................................................................................10
5.2 Drainage Concept...................................................................................................10
6. REFERENCES..................................................................................................................I I
APPENDICES
A Vicinity Map
B Hydrologic Computations
C Hydraulice Computations
D Detention & Water Quality Pond Calculations
D BMP Schedule & Cost Estimate
lim
1. GENERAL LOCATION AND DESCRIPTION
1.1. Location
The site is located in Section 20, Township 7 North, Range 68 West of the 61h P.M. in the
City of Fort Collins, CO. The site is bounded by East Drake Road on the south, the
Sidehill development on the west, north and east.
1.2. Description of Property
The Cargill Expansion area that is being considered with this drainage design is
approximately 6.5 acres of the total 30.73 acre Cargill property. There are a total of seven
existing buildings and a pavilion on the Cargill property. The existing buildings include
offices, laboratories and greenhouses.
Prior to any development, the site was originally with native weeds and grasses and
irrigated crops. On site soils on the Cargill property are primarily Nunn Loam and
Stoneham Loam with small areas of Santana Loam and Larimer-Stoneham complex. The
entire site is composed of Hydrologic Groups B and C. according to the USDA soils
survey maps. Group B soils have a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately well drained or well drained soils that have moderately fine
texture to moderately coarse texture. These soils have a moderate rate of water
transmission. Group C soils have a slow infiltration rate when thoroughly wet. These
consist chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of water
transmission. The majority of the building site is predominantly Hydrologic Group C.
The existing runoff coefficient for the overall site prior to construction is 0.20 for the 2
year condition. The site is zoned Low Density Mixed Use Neighborhood (LMN). The site
is within Flood Insurance Zone C, the areas determined to be outside the 500-year flood
plain, according to the FEMA Flood Insurance Rate Map, Community -Panel No. 0801
01-0193-E, dated March 18, 1996.
The proposed development is a phased development. Phase 1 includes the proposed
office and shop building, private drives, parking and two detention ponds. Phase 2
includes two greenhouses and the associated asphalt drives.
1.3. Major Basin Description
This site is located in the Foothills Drainage Basin. The site is not located within the
FEMA designated 100 year floodplain or the City designated flood plain.
1.4. Sub -basin Description
This site is located in Subbasin 56 of the Foothills Basin Master Plan. Stormwater runoff
from the Cargill site drains overland generally from north to south at slopes ranging from
0.5% to 2.0%. Runoff from the entire Cargill site currently flows to an onsite water
quality pond and released into the storm system or to Drake Road where it is captured in
inlets and conveyed to the Poudre River.
2. DRAINAGE DESIGN CRITERIA
2.1. Regulations
Drainage for this site has been designed to meet or exceed the "City of Fort Collins
Stormwater Criteria Manual' specifications, the City of Fort Collins Cache la Poudre
Basin Master Plan and the update to Chapter 26 of the City Code. Where applicable, the
criteria established in the "Urban Storm Drainage Criteria Manual' (UDFCD), 2001 has
been used.
2.2. Development Criteria Reference and Constraints
Stormwater runoff from this site has been routed to conform to the requirements of the
City Stormwater Department. Detention is required for this site with a 2 year historic
release rate. Detention is being provided for all of the new construction. The existing
structures will not be considered in the drainage and detention design for this site but are
continuing to have water quality extended detention provided in the existing pond.
Water quality facilities are required for the proposed improvements and are being
provided by water quality extended detention in the ponds and pretreatment basins.
2
2.3. Hydrologic Criteria
Runoff computations were prepared for the 10 year minor and 100 year major storm
frequency utilizing the Rational Method. All hydrologic calculations associated with the
basins are included in Appendix B of this report.
2.4. Hydraulic Criteria
Necessary hydraulic calculations are provided and prepared in accordance with the City
of Fort Collins Drainage Criteria and the Urban Area Drainage Criteria Manual.
3. DRAINAGE FACILITY DESIGN
3.1. General Concept
All of the runoff from this site historically sheet flows to the adjacent streets and is
intercepted by the existing inlets located in East Drake Road. With the previous
development on site, a water quality pond was provided and will remain with this
proposal.
The proposed improvements will disturb approximately 5.4 acres of the entire 30.73 acres
on the Cargill campus. Runoff from this site will be collected in proposed private storm
pipes or will surface flow to the proposed detention ponds on site. The ponds were sized
to accommodate the 100 year storm event with a 2 year historic release rate.
3.2. Specific Flow Routing
The proposed development has been divided into 2 basins, each corresponding with the
appropriate detention pond that collects runoff from that basin. Smaller portions of those
basins were considered when sizing the onsite storm systems. A summary of the drainage
patterns within each basin is provided in the following paragraphs.
Basin 1 encompasses the east portion of the site including the south and east parking lots
and the proposed Pond 1 site. A portion of the runoff from this basin will directly enter
the proposed Pond 1 and a portion will enter a grassed Swale prior to entering Pond 1.
Pond 1 will have water quality extended detention. The water quality extended detention
is required for this site and a grassed swale is intended to provide additional treatment for
a portion of the basin in order to forego the requirement for pervious pavement on site.
3
Pond 1 will discharge into the existing storm manhole located at the southeast corner of
Basin 1.
Basin 2 includes the remainder of the proposed development including the parking and
private drive on the west, the entirety of the proposed office building, two greenhouses to
be constructed in phase 2 and the associated private asphalt drives. Runoff from this
basin will either directly enter the proposed detention and water quality pond or will be
collected in a private storm pipe and conveyed west and south into the proposed Pond 2.
Pond 2 will have water quality extended detention and two pretreatment basins. Runoff
that flows from the parking lot will enter a pervious gravel area with an underdrain that
will provide the required LID strategy. The water quality extended detention is required
for this site and the LID enhancements are intended to provide additional treatment in
order to forego the requirement for pervious pavement on site.
Pond 2 will discharge into the existing inlet located in the south flowline of Drake Road
near the middle of the site.
The 2 year historic runoff for the 5.4 acres was calculated to be 1.5 cfs. This allowable
release rate was divided between the two ponds with Pond 1 having a release rate of 0.70
cfs and Pond 2 having a release rate of 0.8 cfs.
3.3. Drainage Summary
Drainage for this site was designed to conform to the City of Fort Collins stormwater and
water quality requirements. Water quality is provided for a majority of the site utilizing
grassed swales. Water quality for the site is also provided by including extended
detention volume in the proposed detention ponds.
4
4. STORMWATER MANAGEMENT CONTROLS
4.1 SWMP contact information
Permit holder:
Name:
Dohn Construction
Address:
2642 Midpoint Drive, Fort Collins, CO
Phone Number:
970-490-1855
Email Address:
tannand@dohnconstruction.com
Appointed agent:
Name:
Address:
Phone Number:
Email Address:
4.2 Identification and location of all potential pollution sources
Potential Pollutant Source Activity ' r, '
Poientiai Pollutant�0enerated "`
a
"z Applicable to
this project-, n--
Disturbed Areas
Sediment
X
Soil stockpiles
Sediment
X
Travel to adjacent public streets
Tracked sediment
X
Contaminated soils
Sediment, chemicals
Loading and unloading chemicals
Chemicals
Outdoor storage of chemicals
Chemicals
On site equipment maintenance
Oil, grease
On site equipment fueling
Diesel, gasoline
X
Dust generating activities
Particulates, sediment
X
Use of fertilizer, pesticides, herbicides
Fertilizer, pesticides
Use of detergents, solvents, oils
Detergents, solvents, oil
X
Waste dumpsters, waste piles
Chemicals
X
Concrete washout
Concrete, sediment
X
On site equipment washing
Detergents, oil
On site asphalt batch plant
Asphaltic cement, sediment
On site concrete batch plant
Cement, sediment
Portable toilets
Domestic sewage
X
5
4.3 Best Management Practices (BMP's) for Stormwater Pollution Prevention
Structural Practices for Erosion and Sediment Control
Structural practices for the site will consist mainly of silt fence, straw wattles and rock sock
filters and are described in detail in the following paragraphs. These BMP's are expected to
change as the construction progresses and it is the responsibility of the contractor to ensure
appropriate BMP's are in place and/or removed at the appropriate time in the construction
sequence. All temporary and permanent erosion and sediment control practices must be
maintained and repaired as needed to assure continued performance of their intended function.
Silt fence and rock sock filters shall be in place prior to commencement of construction
activities. During clearing and grubbing necessary for silt fence installation, all cleared material
shall be placed on the uphill side so that if erosion occurs from the cleared material, the sediment
will be trapped and not transported downstream. Rock socks shall be implemented in the existing
curb line of Drake Road as shown on the Drainage & Erosion Control Plan.
All BMP's shall be installed per the details shown on the construction plan set.
Temporary & Permanent Structural BMP's:
Structural BMP�
Approximateaocation-on site.;
-Project
Applicable to this
Silt Fence
Site perimeter, refer to site map
X
Straw bale dams
Rock Socks
At existing pond outlet, refer to site map
X
Earthen diversion dams
Vegetated swales
Maintain existing vegetation in Swale
X
Sediment trap/pond
In Pond 2
X
Pipe slope drains
Geogrid
Inlet/outlet protection
At pipe outlets as shown on EC plan
X
Culverts
Riprap
At pipe outlet, refer to site map
X
Erosion control mats
Inlet protection
6
Non -Structural Practices for Erosion and Sediment Control:
Soils exposed during the earthwork phase and landscape prep phase shall be kept in a roughened
condition by ripping or disking along land contours until mulch, vegetation, or other permanent
erosion control is installed. No large amount of soils (in excess of 15 yards) will be allowed to be
stock piled on site. Overburden from the utility pipe trenching will be piled adjacent to trenches
upstream of sediment controls and will be replaced in the trenches within 72 hours.
Excess excavated materials from the demolition and grading phases of the project that cannot be
reused on site will be exported as it is excavated. This includes any asphalt pavement from the
existing site that is to be removed.
A vehicle tracking pad will be installed at a location most beneficial to the site construction as
determined by the contractor. Vehicles will not be permitted in the excavated area if soil is
muddy. Gravel sub base will be placed and compacted in the areas indicated for pavement
following excavation. In the current pre construction state the site enables tracking of silt onto
the adjacent streets during wet conditions. During construction activities the street will be
monitored for foreign debris tracked out of the site and mechanical sweeping and clean up will
be performed as needed.
No area shall remain exposed by land disturbing activity for more than thirty (30) days before
required temporary or permanent erosion control (e.g. seed/mulch, landscaping, etc.) is installed.
Temporary & Permanent non-structural BMP's:
Non -Structural BMP
Approximaie location on site
Applicable to this ,•
L��a zee
. .�'9?'S s2J4 d r1i indE.�
Project
.vim,
Surface roughening
Entire construction area
X
Soil stockpile height limit (less
than 10')
Perimeter vegetative buffer
North and west sides of construction area
X
Minimization of site disturbance
Entire site
X
Mulch
Seed & mulch stockpiles after 30
days
Stockpile toe protection (silt fence,
wattles or ditch)
Preservation & protection of
west and north sides of construction area
X
existing vegetation & trees
Good site housekeeping (routine
Entire Construction area
X
cleanup of trash & constr debris)
Heavy equip staged on site,
properly maintained & inspected
Staging area
X
daily (no onsite maintenance)
7
4.4 BMP Implementation
1) Phased BMP Implementation
BMP's are expected to change as the construction progresses and it is the responsibility of
the contractor to ensure appropriate BMP's are in place and/or removed_at the appropriate
time in the construction sequence. A construction sequence schedule has been included on
the Drainage & Erosion Control Plan and included in the construction plans for this site.
All BMP's shall be inspected and repaired or replaced as required to satisfy the conditions of
the Stormwater Discharge Permit. All BMP's must be maintained and repaired as needed to
assure continued performance of their intended function.
Refer to Appendix D for the implementation schedule.
Refer to Appendix D for the BMP Cost Estimate.
8
2) Materials Handling and Spill Prevention:
Materials Handling & Spill
Approximate location on site
=_ Applicable to this `
Prevention BMP
Project
Portable toilets, anchored &
Refer to site map
X
located away from drainages
Fuel storage located in bulk tanks
with secondary containment &
spill kit
Mobile fueling performed at least
200 feet away from drainages &
Refer to site map
X
fully attended
Fertilizers, form oil, solvents,
cleaners, detergent stored in 55 gal
Refer to site map
X
or smaller containers, kept in
storage units
Dumpsters containing used
chemicals containers & liquid
Refer to site map
X
wastes kept covered
Equipment cleaning (on site) uses
no detergents & flows to onsite
retention basin
In case of a release of fuel or other
chemicals, absorbent booms or
earthen berms will be immediately
Location of spill
X
constructed to contain the spill &
prevent runoff to adjacent surface
waters
MSDS sheets for onsite chemicals
will be kept at the construction
Construction Trailer
X
trailer to facilitate spill response &
cleanup
3) Dedicated Asphalt or Concrete Batch Plant:
Not proposed with this development
4) Vehicle Tracking Pad:
Vehicle tracking control pad shall be installed wherever construction vehicle access routes
intersect paved public roads. Vehicle tracking control pads shall be installed to minimize the
transport of sediment (mud) by runoff or vehicles tracking onto the paved surface. Any mud
tracked to public roads shall be removed on a daily basis and after any significant storm that
causes sediment to be transported. It is unlawful to track sediment/mud onto public streets
and may be enforced by the City of Fort Collins or by the State of Colorado.
9
5) Waste Management and Disposal:
Portable toilets will be anchored & periodically maintained by waste management company.
Dumpsters on site will be covered & periodically emptied by waste management company.
Concrete waste will be allowed to harden and then will be removed from site.
No washing activities will occur on site.
Location of the concrete washout is shown on the site map. The washout will be sufficiently
deep to accommodate all anticipated concrete truck wash water. Waste concrete will be
allowed to harden and be removed from site periodically as the washout reaches 50% of its
capacity. Truck wash water will not be allowed to reach the curb & gutter or any other water
course.
6) Groundwater and Stormwater Dewatering:
No groundwater was encountered during soils exploration therefore ground water is not
anticipated to be an issue. If groundwater is encountered a groundwater discharge permit
shall be obtained and a detailed report shall be completed describing the location and the
route of where pumped groundwater will be conveyed and the measures taken to prevent the
transport of any pollutants to downstream waters.
7) Inspection & Maintenance:
It is required that routine site inspections are performed to effectively address maintenance
and repair of Best Management Practices (BMP's). The site inspections are to performed by
the contractor or an inspector designated by the administrator at a minimum of once every
fourteen (14) calendar days on active construction sites and after any significant stone event
(an event causing runoff). As part of the site inspections the inspector is required to keep
documentation of
all inspections and BMP maintenance, including an updated Site Map indicating new BMP's
or the removal of BMP's since the previous inspection.
Any maintenance, repair, or necessary installation of BMP's that are noted during the
inspection must be completed within seven (7) calendar days from the date of the inspection.
10
5. CONCLUSIONS
5.1. Compliance with Standards
All computations that have been completed within this report will be in compliance with
the City of Fort Collins Erosion Control Reference Manual for Construction Sites and the
City of Fort Collins Stormwater Criteria Manual.
5.2. Drainage Concept
The proposed drainage concepts presented in this report and on the construction plans,
will adequately provide for stormwater quality treatment for the proposed improvements.
Conveyance elements have been designed to convey required flows in the proposed
grassed swales and the existing water quality facility and ultimately to the Cache la
Poudre River.
If, at the time of construction, groundwater is encountered, a Colorado Department of
Health Construction Dewatering Permit will be required.
Is
6. REFERENCES
1. City of Fort Collins, "Storm Drainage Criteria Manual", (SDCM), dated March
1999.
2. Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria
Manual", Volumes 1 and 2, dated June 2001, and Volume 3 dated September
2001.
3. "Final Drainage and Erosion Control Report for Cargill Secondary Use Building"
by DWM Civil Engineers dated May 5, 2007.
12
APPENDIX A
VICINITY MAP
9
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6
I
CONSTRUCTION SEQUENCE
PROJECT: CANCEL OFFICE EXPANSON DATE: 12/18/13
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7 OF 11
1101 No. 339-02
APPENDIX B
HYDROLOGIC COMPUTATIONS
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APPENDIX C
HYDRAULIC COMPUTATIONS
C
Scenario: Base
Bentley StormCAD V8i
Storm system.stc Bentley Systems, Inc. Haestad Methods Solution Center [08.11.00.401
12118/2013 27 Siemon Company Drive Suite 200 W Watertown, CT Page 1 of 1
06795 USA +1-203-755-1666
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APPENDIX D
DETENTION & WATER QUALITY POND CALCULATIONS
E7
100-YEAR DETENTION VOLUME REQUIRED
EAST DETENTION POND (POND 1)
FAA METHOD
.LOCATION:
Cargill office Basin 1
PROJECT NO:
347-02
COMPUTATIONS BY:
PPK
DATE:
12/18/2013
Equations:
A trib. To pond =
Qo = CIA
Cioo =
Vi=TCIA=TQo
Developed C A =
Vo =K QPo T
()Po =
S=Vi -Vo
K=
Rainfall intensity from City of Fort Collins IDF Curve
0.91 acre
0.82
0.7 acre
0.70 cfs
Storm
Duration, T
(min)
Rainfall
Intensity, i
(in/hr)
Qp
(cfs)
Vol. In
Vi
(ft)
Vol. Out
Vo
(ft)
Storage
S
(ft)
Storage
S
(ac-ft)
5
9.95
7.4
2227
0
2227
0.051
10
7.72
5.8
3456
0
3456
0.079
20
5.60
4.2
5014
420
4594
0.105
30
4.52
3.4
6071
840
5231
0.120
40
3.74
2.8
6698
1260
5438
0.125
50
3.23
2.4
7231
1680
5551
0.127
60
2.86
2.1
7683
2100
5583
0.128
70
2.62
2.0
8211
2520
5691
0.131
80
2.38
1.8
8525
2940
5585
0.128
90
2.22
1.7
8945
3360
5585
1 0.128
100
2.05
1.5
9178
3780
5398
0.124
110
1.93
1.4
9505
4200
5305
0.122
120
1.80
1.3
9671
4620
5051
0.116
130
1.60
1.2
9313
5040
4273
0.098
140
1.40
1.0
8775
5460
3315
0.076
150
1.20
0.9
8059 1
5880
2179
0.050
160
1.15
0.9
8238
6300 1
1938
0.044
170
1.10
0.8
8372
6720
1652
0.038
180
1.05
0.8
8462
7140
1322
0.030
Required Storage Volume: 5691 ft3
0.131 acre-ft
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:Y
Ul
100-YEAR DETENTION VOLUME REQUIRED
WEST DETENTION POND (POND 2)
FAA METHOD
LOCATION:
Cargill office
PROJECT NO:
347-02
COMPUTATIONS BY:
PPK.
DATE:
12/18/2013
Equations:
A trib. To pond =
4.5 acre
QD = CIA
C100 =
0.77
Vi = T C I A= T QD
Developed C A=
3.5 acre
Vo =K QPo T
QPo =
0.80 cfs
S=Vi -Vo
K=
1
Rainfall intensity from City of Fort Collins IDF Curve
Storm
Duration, T
(min)
Rainfall
Intensity, i
(in/hr)
QD
(cfs)
Vol. In
Vi
(ft3)
Vol. Out
Vo
(ft)
Storage
S
(ft)
Storage
S
(ac-ft)
5
9.95
34.5
10343
0
10343
0.237
10
7.72
26.7
16050
0
16050
0.368
20
5.60
19.4
23285
480
22805
0.524
30
4.52
15.7
28191
960
27231
0.625
40
3.74
13.0
31102
1440
29662
0.681
50
3.23
11.2
33576
1920
31656
0.727
60
2.86
9.9
35676
2400
33276
0.764
70
2.62
9.1
38129
2880
35249
0.809
80
2.38
8.2
39584
3360
36224
0.832
90
2.22
7.7
41538
3840
37698
0.865
100
2.05
7.1
42620
4320
38300
0.879
110
1.93
6.7
44137
4800
39337
0.903
120
1.80
6.2
44906
5280
39626
0.910
130
1.60
5.5
43243
5760
37483
0.860
140
1.40
4.9
40748
6240
34508
0.792
150
1.20
4.2
37422
6720
30702
0.705
160
1.15
4.0
38254
7200
31054
0.713
170
1.10
3.8
38877
7680
31197
0.716
180
1.05
3.6
39293
8160
31133
0.715
Required Storage Volume: 39626 W
0.910 acre-ft
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STAGE - STORAGE TABLE
100-YEAR
LOCATION: Cargill office
PROJECT NO: 347-02
COMPUTATIONS BY: PPK
DATE: 12/18/2013
Extended Water Quality Volume Required =
100 yr Detention Volume Required =
POND 1 (east pond)
WQCV
100yr WSEL
0.022
0.131
0.152
Stage
(ft)
Surface
Area
(ft`)
Incremental
Storage
(ac-ft)
Total
Storage
(ac-ft)
4922
0
4923
0
0.000
0.000
4924
932
0.007
0.007
4924.4
2,202
0.015
0.022
4925
3,945
0.053
0.060
4925.6
9,367
0.092
0.152
4926
12,515
0.176
0.236
4926.5
18,141
0.175
0.411
Extended Water Quality Volume Required = 0.119
100 yr Detention Volume Required = 0.910
1.029
POND 2 (west pond)
WQCV
100 YR WSEL
Stage
(ft)
Surface
Area
(ft`)
Incremental
Storage
(ac-ft)
Total
Storage
(ac-ft)
4922
0
4923
4,347
0.033
0.033
4923.58
8,749
0.085
0.119
4924
11,937
0.180
0.213
4925
17,680
0.338
0.551
4925.92
27,884
0.479
1.029
4926
28,735
0.528
1.078
4926.5
26,000
0.314
1.392
1.315
APPENDIX E
BMP SCHEDULE & COST ESTIMATE
PROJECT:CONSTRUCTION SEQUENCE
OFFICE EXPANSIONDATE: 12/18/13
CONSTRUCTION -
eeeeeeeeeee®
DETENTION WO PONDS
BEST MANAGEMENT PRACTICES
STRUCTURAL
SILT FENCE 8ARRIERS
C4,NT#UR FURROWS
TRAP /
VEHICLE TRACKING .SEDIMENT
CONCRETE WASHOUT
MULCHING / SEALANT
SEDIMENT/EROSION CONTROL
BEST MANAGEMENT PRACTICES (BMPs)
COST OPINION SPREADSHEET
CARGILL OFFICE EXPANSION
Item
No.
BMP
ID
Unit
Installation
Unit Cost
Quantity
Cost
1
Check Dam
CDR
LF
$0.00
2
Check Dam (Reinforced)
CDR
LF
$0.00
3
Concrete Washout Area
CWA
EA
$1,200.00
1
$1,200.00
4
lConstruction Fence
CF
I L
1 $0.00
5
Construction Markers
CM
LF
$0.00
6
Culvert Inlet Filter
CIF
LF
$0.00
7
Dewatering
DW
EA
$0.00
8
Diversion Ditch (Unlined)
DD
LF
$0.00
9
Diversion Ditch (ECM or plastic)
DD
LF
$0.00
10
Sediment/Erosion Control Matting
ECM
SY
$9.50
400
$3,800.00
11
1 Inlet Protection
IP
LF
$0.00
12
Reinforced Rock Berm
RRB
LF
$0.00
13
Sediment Basin
SB
LS
$0.00
14
Sediment Control Log (Wattle)
SCL
LF
$4.60
30
$138.00
15
Seeding and Mulching
SM
AC
$0.00
16
Silt Fence
SF
LF
$3.00
540
$1,620.00
17
Rock Sock
RS
LF
$10.00
8
$80.00
Stabilized Staging Area
SSA
SY
$0.00
Surface Roughening
SR
AC
$0.00
L22
Temporary Stream Crossing
TSC
EA
$0.00
Topsoil (6-inch Lift)
TSL
AC
$0.00
Vehicle Tracking Control
VTC
EA
$1,500.00
1
$1,500.00
Subtotal $8,338.00
Maintenance & replacements (50%) $4,169.00
#1 Erosion control amount $12,507.00
L.L2.
Reseeding I
AC $1,200.00 1 5.4
$6,480.00
Erosion control escrow (greater of #1 & #2) $12,507.00