HomeMy WebLinkAboutMONTAVA - PHASE G & IRRIGATION POND - BDR210013 - SUBMITTAL DOCUMENTS - ROUND 5 - STORMWATER MANAGEMENT PLANMONTAVA PHASE G
EROSION CONTROL REPORT /
STORMWATER MANAGEMENT REPORT
CITY OF FORT COLLINS, COLORADO
APRIL 11TH, 2023
MARTIN/MARTIN PROJECT NO. 19.1354
OWNER: HF2M COLORADO
430 N. COLLEGE AVE. SUITE 410
FORT COLLINS, CO 80524
(512) 507-5570
MAX MOSS
PREPARED BY: MARTIN/MARTIN, INC.
12499 WEST COLFAX AVENUE
LAKEWOOD, COLORADO 80215
PHONE: (303) 431-6100
DEVELOPER: HF2M COLORADO (APPLICANT)
430 N. COLLEGE AVE. SUITE 410
FORT COLLINS, CO 8052
(512) 507-5570
MAX MOSS
CONTRACTOR: TBD
SWMP ADMINISTRATOR: TBD
PRINCIPAL IN CHARGE: JEFF A. WHITE, P.E.
PROJECT MANAGER: RACHEL L. SCHALL, P.E.
PROJECT ENGINEER: TYLER J. WEIAND, E.I.T. I
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TABLE OF CONTENTS
A. OVERVIEW .............................................................................................. 3
B. PROJECT DESCRIPTION AND NATURE OF CONSTRUCTION .... 4
PROJECT DESCRIPTION: ......................................................................................... 4
SITE LOCATION: ......................................................................................................... 4
EXISTING SITE CONDITION: ................................................................................... 5
PROPOSED CONSTRUCTION ACTIVITIES: .......................................................... 8
C. POTENTIAL POLLUTANT SOURCES: ................................................ 9
ALL DISTURBED AND STORED SOILS: ................................................................. 9
VEHICLE TRACKING OF SEDIMENTS: ............................................................... 10
MANAGEMENT OF CONTAMINATED SOILS ..................................................... 10
LOADING AND UNLOADING OPERATIONS ....................................................... 10
OUTDOOR STORAGE OF CONSTURCTION SITE MATERIALS, BUILDING
MATERIALS, FERTILIZERS AND CHEMICALS ................................................. 11
BULK STORAGE OF MATERIALS .......................................................................... 11
VEHICLE AND EQUIPMENT MAINTENANCE AND FUELING ....................... 11
SIGNIFICANT DUST OR PARTICULATE GENERATING PROCESSES ........... 12
ROUTINE MAINTENANCE ACTIVITES INVOLVING FERTILIZERS,
PESTICIDES, DETERGENTS, FUELS, SOLVENTS, AND OILS ......................... 13
ON-SITE WASTE MANAGEMENT PRACTICES ................................................... 13
CONCRETE TRUCK/EQUIPMENT WASHING, INCLUDING THE CONCRETE
TRUCK CHUTE AND ASSOCIATED FIXTURES AND EQUIPMENT ................ 13
DEDICATED ASPHALT AND CONCRETE BATCH PLANTS ............................. 14
NON-INDUSTRIAL WASTE SOURCES SUCH AS WORKER TRASH AND
PORTABLE TOILETS ................................................................................................ 14
SAW CUTTING AND GRINDING ............................................................................. 14
OTHER NON-STORMWATER DISCHARGES INCLUDING CONSTRUCTION
DEWATERIG NOT COVERED UNDER THE CONSTRUCTION DEWATERING
2
DISCHARGES GENERAL PERMIT AND WASH WATER THAT MAY
CONTRIBUTE POLLUTANTS TO THE MS4 .......................................................... 15
D. CONSTUCTION CONTROL MEASURES .......................................... 15
E. INSTALLATIONAND REMOVAL SEQUENCE OF
CONSTRUCTION MEASURES ................................................................. 21
GENERAL .................................................................................................................... 21
INITIAL ....................................................................................................................... 21
INTERIM ..................................................................................................................... 22
FINAL .......................................................................................................................... 23
F. PHASING ................................................................................................ 23
G. MAINTENANCE AND INSPECTION REQUIREMENTS ................ 23
H. FINAL VEGETATION AND STABILIZATION ................................. 24
SOIL AMMENDMENTS ............................................................................................ 25
PERMANENT SEED MIX ......................................................................................... 25
I. REFERENCES ........................................................................................ 26
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A. OVERVIEW
This report represents a Stormwater Management Plan (SWMP) for the proposed
Montava Phase G Construction (hereafter referred to as “PROJECT”). This plan was
prepared based upon the regulatory requirements and guidelines set forth by the Colorado
Department of Public Health and Environment Water Quality Control Division –
Stormwater Program’s “Stormwater Management Plan Preparation Guidance” January
2021 revision; the “Urban Storm Drainage Criteria Manual – Volumes 1-3” current
revisions; and the “Fort Collins Stormwater Criteria Manual” December 2018 revision.
This report identifies potential sources of pollution which may reasonably be expected to
affect the quality of stormwater discharges associated with construction. Furthermore,
this report describes the practices to be used to reduce, or possibly eliminate, these
potential pollutants from impacting the quality of water. The SWMP shall be completed
and implemented by the time construction activities begin until final stabilization. The
SWMP shall be revised as necessary during construction activities so that it accurately
reflects the conditions and current practices found on-site as construction progresses. A
copy of the current updated SWMP shall be kept on-site at all times and available for
review by all jurisdictions having authority over stormwater discharge from the project
site.
This report puts forth recommendations for Best Management Practices (BMPs) and
provides a description and/or detailed drawings of how these practices are to be installed,
implemented and maintained. The contractor is responsible for complying with ALL
requirements of the Colorado Department of Public Health and Environment Storm
Water Discharge Permit including any changes to this SWMP to meet the requirements
of the Permit.
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B. PROJECT DESCRIPTION AND NATURE OF
CONSTRUCTION
PROJECT DESCRIPTION:
The proposed PROJECT will include new construction of a 1,512,000 gross square feet
(34.7 acre) traditional neighborhood development (TND) in northeast Fort Collins. The
development will include a mix of residential, commercial, and industrial uses with
roads, parking areas, drainage features, and associated appurtenances. Utilities will be
installed in support of the new development, along with appropriate stormwater facilities.
Water quality to mitigate and treat stormwater runoff from the site will be provided
through 5 bioretention rain gardens, a linear bioretention swale, a Stormtech
Underground Water Quality structure, and 2 full spectrum detention ponds, one of which
is just off the neighborhood property to the north. In addition to the neighborhood
development, improvements will be constructed for Mountain Vista Drive running along
the south border of the neighborhood. North Timberline Road and the Number 8 Ditch to
the east will also undergo improvements, along with extending the road north to the
northern edge of the proposed neighborhood. The number 8 Ditch will be piped all the
way north to Country Club Road.
SITE LOCATION:
The PROJECT site is located in Fort Collins’ Mountain Vista Subarea (hereafter referred
to as “SUBAREA”), found in the South ½ of Section 32, Township 8 North, Range 68
West of the 6
th
Principal Meridian, City of Fort Collins, County of Larimer, State of
Colorado. The PROJECT site GPS coordinates are 40°36’42.93”N and 105°1’54.42”W.
The overall project consists of 118.7 acres of disturbed area.
The PROJECT site is bound to the north by undeveloped land, to the east by the #8 Ditch
Corridor, to the south by Mountain Vista Drive, and to the west by the Storybrook
Subdivision. Refer to the vicinity map below and in the Appendix.
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Figure 1: Vicinity Map, NTS
EXISTING SITE CONDITION:
Soil Properties:
The existing construction site topography generally slopes from west to east at 0-2%.
Aside from Mountain Vista Drive, native grasses cover the majority of the construction
site with a couple of gravel access roads. The site has roughly 99% vegetative cover.
According to the USDA Web Soil Survey, the property consists of predominantly
Stoneham loam with small areas of Satanta loam. Based on boring hole data,
groundwater is expected at a minimum depth of 24 feet below existing grade. The soils
on-site are predominantly Hydrologic Soil Type B, which yield a low potential for runoff
during rainfall with a moderately high permeability. The soil erodibility is considered
low.
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Pathway to the Nearest State Water:
The project site is within the Upper Cooper Slough Drainage Basin, which encompasses
approximately 26 square miles extending north from the Larimer and Weld Canal and
west of Interstate 25. The basin is primarily undeveloped farmland except for the
Anheuser-Busch brewery site. The southern portion of Upper Cooper Slough is
experiencing rapid urbanization, especially with housing developments. Stormwater
within this basin flows generally from north to south, with runoff ultimately being
captured by the Larimer and Weld Canal. During large storm events, runoff spills into
Lower Cooper Slough from the Larimer and Weld Canal. Located on the west side of the
basin, the No. 8 Ditch runs north to south and is a primary conveyance of stormwater to
the Larimer and Weld Canal. The storm runoff from Upper Cooper Slough Drainage
basin is tributary to Boxelder Creek and Lower Cooper Slough, which both end at the
Cache la Poudre River.
The PROJECT site is historically one basin that flows east into the Number 8 Ditch. As
part of the Timberline Road improvements, the number 8 Ditch will be piped below
Timberline Road. The proposed PROJECT site will utilize 5 proposed rain gardens, a
linear bioretention swale, a Stormtech Underground Water Quality Structure, and 2
proposed detention ponds while routing flows to the Timberline Road Pipeline. The
ponds, swale, and rain gardens are designed for the 100-year storm. All runoff from the
PROJECT site eventually discharges into the Timberline Road Pipeline, which eventually
leads to the Cache la Poudre River. Stormwater detention for the PROJECT site will
provided by ponds located in the middle of the site and just north of the neighborhood.
Water quality treatment for the PROJECT will be provided by the two proposed ponds,
five bioretention rain gardens, the Stormtech Underground Water Quality Structure, and
the bioretention swale. The two ponds are constructed as full spectrum detention ponds.
7
Figure 2: Major Drainage Basin
Anticipated allowable sources of non-stormwater discharge:
In addition to discharge from storm water, landscape irrigation return flows may be
anticipated from tributary landscaped areas. There are no wetlands or springs anticipated
to contribute to site discharge.
Summary of ground contamination:
There is no known ground contamination on or around the project site.
Distances from riparian or sensitive areas:
The project site is not located near any riparian or sensitive areas
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PROPOSED CONSTRUCTION ACTIVITIES:
The Montava Phase G project consists of a traditional neighborhood development of
34.71-acres in the Montava community, improving Mountain Vista Drive running along
the south border of the neighborhood, improving North Timberline Road to the east and
extending it to the northern border of the neighborhood, and improving the Number 8
Ditch to the east, including piping a portion of it north up to Country Club Road. The
project will be constructed in one phase. Construction activity will include mobilization,
demolition, clear and grub, overlot grading, foundation excavation, utility installation,
vertical construction, paving operations, and landscaping/stabilization. Homebuilding and
community amenities will follow the major infrastructure construction. Environmental
impacts on the surrounding properties as a result of these construction activities are not
anticipated.
The overall area of Phase G encompasses 79.4 acres, which includes the neighborhood
property, 25.5 acres to the north for a regional full spectrum pond and recreational fields,
and 19.2 acres to the south and east for the roadway and Number 8 Ditch improvements.
An additional 39.3 acres to the north and east of the neighborhood are utilized to borrow
soil for this proposed project in addition to Montava Phase E, under separate submittal.
The Phase G and offsite boundaries can be viewed in the erosion control plans in
Appendix G.
Potential permits that may be needed are a Development Construction Permit (DCP), a
Right-of-Way Permit (RWP), a Stockpiling in Fort Collins Permit, an Emission Permit
from the Colorado Department of Public Health and Environment, a Discharge Permit
from the Colorado Department of Health, and more. Contractor to verify and obtain the
necessary permits.
Total Area of Project = 118.7 ac
Disturbance on Site = 79.4 ac
Disturbance off Site = 39.3 ac
Total Area of Staging and Storage = 2.00 ac
Total Imported (+)/Exported (-) Material = -45325 cy
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C. POTENTIAL POLLUTANT SOURCES:
The potential for each of the possible pollutant sources to contribute pollutants to storm
water discharge in the list below have been evaluated with regards to the frequency of the
activity, the physical characteristic of the area, the ability of containment measure to
prevent and contain leaks and/or spills, proximity to waterways or drainage facilities, the
concentration and toxicity of materials and the possible contamination of storage
facilities and materials. If it was determined that the source has a reasonable chance of
contributing pollutants to storm water discharge, a specific BMP or combination of
BMPs has been identified to address or mitigate that potential.
ALL DISTURBED AND STORED SOILS:
YES - Soils disturbed during construction activities (site preparation, grading, foundation
excavation, loading and unloading of dirt, utility trenching etc.) have the potential to
introduce sediment into runoff. Silt fence will be used to prevent sediment from leaving
down-gradient of disturbed areas. Water should be applied to disturbed soil surfaces and
backfilled materials consistently to minimize particulate generation from wind. Cover
materials during periods of inactivity and anchor the cover. Surface roughening will be
used to stabilize disturbed areas after 14 days. Temporary seeding and mulching will be
used to stabilize disturbed areas after 30 days. Establish a maximum speed limit or install
traffic calming devices to reduce sediment transport. Inlet protection will be used to help
prevent sediment from entering storm sewer. Street sweeping shall be performed daily
when disturbed soils have tracked onto paved streets. Construction fence will be used to
minimize access to undisturbed areas and limit the area of disturbed soil. Straw waddle
will be used around individual lots in order to catch sediment from concentrated runoff.
Temporarily halt work activities during high wind events greater than 30 mph if
operations would result in off-property transport. Drivers and operators shall unload truck
beds and loader or excavator buckets slowly, and minimize the drop height of materials
to the lowest height possible.
BMP’s: Temporary and Permanent Seeding, Mulching, Stockpile Management, Silt Fence,
Sediment Control Log, Inlet Protection, Street Sweeping and Vacuuming, Construction
Fence, Surface Roughening, Straw Waddle, Wet Suppression
10
VEHICLE TRACKING OF SEDIMENTS:
YES - Mud, dirt, and other debris can be carried form a site on the wheels or
undercarriage of equipment and vehicles onto public roads. When this material dries, it
can become airborne by wind activity or when other vehicles travel on it. This is a health
concern and can cause visibility issues and safety hazards. In order to prevent sediment
from leaving the site via exiting vehicles, a vehicle tracking control pad shall be used for
site access. Construction fence shall be used to limit access to the site from any area other
than through the vehicle tracking control pad. Street sweeping shall occur whenever
sediment is carried onto the street from the site. Nearby inlets shall be protected.
BMP’s: Vehicle Tracking Control, Sediment Control Log, Construction Fence, Street
Sweeping and Vacuuming, Inlet Protection
MANAGEMENT OF CONTAMINATED SOILS
NO - Pre-existing contaminated soils are not anticipated. The following BMP’s shall be
implemented to prevent contamination, and control contamination in the event of a spill:
BMP’s: Good Housekeeping Practices, Stabilized Staging Area, Spill Prevention,
Containment and Control
LOADING AND UNLOADING OPERATIONS
YES - Loading and unloading operations can result in particulate generation, which can
be carried off the site and ultimately collected by runoff. Drivers and operators shall
unload truck beds and loader or excavator buckets slowly and minimize drop height of
materials to the lowest height possible. Haul truck loads shall be completely covered or
enclosed in a way that prevents the material from escaping. Cover materials during
periods of inactivity and anchor the cover.
BMP’s: Where possible, dump trucks and waste trucks entering/exiting the site shall be
covered. The property shall be watered to avoid particulate generation from
loading/unloading. Loading and unloading shall take place on the Stabilized Staging Area
and away from inlets.
11
OUTDOOR STORAGE OF CONSTURCTION SITE MATERIALS,
BUILDING MATERIALS, FERTILIZERS AND CHEMICALS
YES - Wherever possible, chemicals shall be stored in a covered location to prevent
rainwater from directly impacting storage containers. The spill prevention, containment,
and control BMP shall be utilized minimize risks from storing chemicals outside. All
workers on the site shall be trained in spill prevention, containment, and control.
Building materials shall be stored on the Stabilized Staging Area in order to minimize
erosion while accessing stored materials.
BMP’s: Spill Prevention, Containment, and Control, Stabilized Staging Area
BULK STORAGE OF MATERIALS
YES - Bulk storage of materials shall take place in the stabilized staging area and
stockpile. There is no anticipation of liquid chemical storage over 55 gallons, however if
the contractor decides it is needed proper BMPs must be used. See above for outdoor
storage practices.
BMP’s: Good Housekeeping Practices, Stabilized Staging Area, Spill Prevention,
Containment and Control
VEHICLE AND EQUIPMENT MAINTENANCE AND FUELING
YES - On-site vehicle equipment maintenance and fueling increases the risk for spilling
the chemicals used for these activities. Where practical, these activities should occur off-
site. When on-site fueling and maintenance is warranted, it shall occur on the stabilized
staging area. The location of the stabilized staging area is shown on the erosion control
plans. If the location of the stabilized staging area is moved during construction, the
updated location shall be redlined on the approved erosion control plan set.
BMP’s: Good Housekeeping Practices, Stabilized Staging Area, Spill Prevention,
Containment and Control
12
SIGNIFICANT DUST OR PARTICULATE GENERATING
PROCESSES
YES - Soils disturbed during construction activities (site preparation, grading, foundation
excavation, loading and unloading of dirt, utility trenching etc.) have the potential to
introduce sediment into runoff. The project will follow all required “BMPs” articulated in
the Fugitive Dust Manual and a least one additional BMP included during each of the
identified activities in accordance with City Ordinance No. 044,2016. Also a copy of the
Dust Control Manual will be kept in the trailer during construction for reference. Silt
fence will be used to prevent sediment from leaving down-gradient of disturbed areas.
Water should be applied to disturbed soil surfaces and backfilled materials consistently to
minimize particulate generation from wind. Cover materials during periods of inactivity
and anchor the cover. Surface roughening will be used to stabilize disturbed areas after
14 days. Temporary seeding and mulching will be used to stabilize disturbed areas after
30 days. Establish a maximum speed limit or install traffic calming devices to reduce
sediment transport. Inlet protection will be used to help prevent sediment from entering
storm sewer. Street sweeping shall be performed daily when disturbed soils have tracked
onto paved streets. Construction fence will be used to minimize access to undisturbed
areas and limit the area of disturbed soil. Straw waddle will be used around individual
lots in order to catch sediment from concentrated runoff. Temporarily halt work activities
during high wind events greater than 30 mph if operations would result in off-property
transport. Drivers and operators shall unload truck beds and loader or excavator buckets
slowly, and minimize the drop height of materials to the lowest height possible.
BMP’s: Temporary and Permanent Seeding, Mulching, Stockpile Management, Silt Fence,
Sediment Control Log, Inlet Protection, Street Sweeping and Vacuuming, Construction
Fence, Surface Roughening, Straw Waddle, Wet Suppression
13
ROUTINE MAINTENANCE ACTIVITES INVOLVING FERTILIZERS,
PESTICIDES, DETERGENTS, FUELS, SOLVENTS, AND OILS
YES - Wherever possible, chemicals shall be stored in a covered location to prevent
rainwater from directly impacting storage containers. The spill prevention, containment,
and control BMP shall be utilized to minimize risks from storing chemicals outside.
Workers on the site shall be trained in spill prevention, containment, and control.
Additionally, wherever possible, chemicals should be used away from storm inlets and/or
natural drainageways. For example, refueling should take place at least 50’ away from
storm sewer inlets.
BMP’s: Spill Prevention, Containment, and Control
ON-SITE WASTE MANAGEMENT PRACTICES
YES - Trash, demolition debris, and waste can be carried by storm water runoff and/or
wind, contaminating runoff water, and clogging existing facilities. To mitigate this risk,
dumpster should be closed whenever feasible. Dumpsters and/or waste piles shall be
located a minimum of 50 feet from any inlet structures or watercourses. Inspection of
dumpsters for leaks should occur with weekly SWMP inspections.
BMP’s: Good Housekeeping Practices
CONCRETE TRUCK/EQUIPMENT WASHING, INCLUDING THE
CONCRETE TRUCK CHUTE AND ASSOCIATED FIXTURES AND
EQUIPMENT
YES - Concrete waste including waste produced after washing trucks, pumps, and
associated fixtures and equipment can be easily tracked onto adjacent streets with the
potential to contaminate stormwater runoff. Concrete washout areas are specifically
indicated on the plans and should be located a minimum of 50 feet from any inlet
structures or watercourses. At the discretion of the SWMP Administrator, actual concrete
washout locations may vary during construction; however, the current location of
concrete washouts shall be accurately reflected by redlining the construction plan set.
BMP’s: Concrete Washout Area
14
DEDICATED ASPHALT AND CONCRETE BATCH PLANTS
NO - No dedicated asphalt or concrete batch plants will be used on-site.
BMP’s: None.
NON-INDUSTRIAL WASTE SOURCES SUCH AS WORKER TRASH
AND PORTABLE TOILETS
YES - Good housekeeping shall be practiced on-site in order to eliminate stormwater
contamination risk from worker trash and portable toilets. Provide an adequate amount of
trash bins in order to encourage compliance across all workers. Stake portable toilets to
the ground in order to minimize the risk of overturning. Updated portable toilet locations
shall be redlined on the construction plan set. Portable toilets shall be located a minimum
of 50 feet from any inlet structures or watercourses.
BMP’s: Good Housekeeping
SAW CUTTING AND GRINDING
YES - Sawcutting asphalt, concrete, and other masonry materials can be a significant
short term source of fugitive dust. Prevent the public from entering the areas where dust
emissions occur. Temporarily hault work while wind events greater than 30 mph take
place. Downstream inlets shall be protected. Plan sawcutting for days when dry weather
is expected. Use wet wiping, wet sweeping, or vacuuming with HEPA filtration for
equipment and work area clean up and do not cause dust to become airborne during clean
up. Prevent water used for dust control or clean up from entering any public right of way,
drainage facility, or watercourses.
BMP’s: Street Sweeping and Vacuuming
15
OTHER NON-STORMWATER DISCHARGES INCLUDING
CONSTRUCTION DEWATERIG NOT COVERED UNDER THE
CONSTRUCTION DEWATERING DISCHARGES GENERAL PERMIT
AND WASH WATER THAT MAY CONTRIBUTE POLLUTANTS TO
THE MS4
YES - Other identified pollutants might be groundwater dewatering, waterline flushing, irrigation
return flows, irrigation to establish grass, dust creating activities, or compaction activities. If these
pollutants propose an issue, proper BMPs must be used.
BMP’s: Temporary and Permanent Seeding, Mulching, Silt Fence, Inlet Protection, Street
Sweeping and Vacuuming, Surface Roughening, Rock Socks
D. CONSTUCTION CONTROL MEASURES
In addition to the descriptions below, the contractor is encouraged to refer to the “Urban
Storm Drainage Criteria Manual – Volume 3” for comprehensive BMP information
Temporary and Permanent Seeding (TS/PS)
Final stabilization for landscaped areas will be achieved when vegetation has achieved
cover which matches the existing vegetative cover. Because a large area of native grass
will be replaced with permanent seeding, vegetative cover is expected to be improved
from existing conditions as a result of the proposed development. If temporary seeding
becomes necessary, the MHFD seed mixes provided in appendix B or approved equals
shall be used.
The use of mulch in conjunction with temporary seeding shall be required to help protect
the seedbed and stabilize the soil. Clean, weed- and seed-free, long-stemmed grass hay is
preferred because it is less susceptible to removal by wind. Mulch should be applied
evenly at a rate of 2 tons per acre and must be tacked or fastened by an approved method
suitable for the type of mulch used. At least 50 percent of the grass hay mulch, by weight,
should be 10 inches or more in length.
16
Good Housekeeping Practices (GH)
Good housekeeping is a source control BMP. Good housekeeping practices are designed
to maintain a clean and orderly work environment. Poor housekeeping practices result in
increased waste and potential for stormwater contamination. A cleaned and orderly work
site reduces the possibility of accidental spills caused by mishandling of chemicals and
equipment.
Vehicle Tracking Control (VTC)
Vehicle Tracking Control is a sediment removal device for construction equipment and
vehicles entering/exiting the site (as described in the MHFD criteria). Vehicle tracking
control shall be installed at the single access point to the site (on Timberline Road just
north of the roundabout) prior to any land-disturbing activity. VTC pads shall be
maintained in working order according to the VTC detail in the erosion control plans.
Stabilized Staging Area (SSA)
The stabilized staging area shall be used for parking, storage, and unloading and loading
operations. The SSA shall consist of 3” minimum thickness of granular material, and
shall be large enough to fully contain parking, storage, and unloading and loading
operations. For this PROJECT site, the existing asphalt parking lot will be used as a SSA.
Construction Fence (CF)
A construction fence restricts site access to designated entrances and exits and delineates
construction site boundaries.
17
Concrete Washout Area (CWA)
The Concrete Washout Area is a sediment-trapping device as described in the MHFD
criteria. Concrete washout area(s) shall be installed prior to any concrete placement on-
site. All concrete delivery truck chutes, concrete pumps, and any other concrete placing
devices shall be cleaned out at the designated concrete washout area. The discharge of
water containing concrete waste and/or sediment to adjacent waterways, wetlands, other
properties, etc. is prohibited. The contractor shall redline the approved SWMP located in
the construction trailer to indicate the current location of all CWAs.
Stockpile Management (SM/SP)
Stockpile management includes measures to minimize erosion and sediment transport
from soil stockpiles. It should be used when soils or other erodible materials are stored at
the construction site. Special attention should be given to stockpiles in close proximity to
natural or manmade storm systems. Updated SM/SP locations shall be redlined on the
approved SWMP located in the construction trailer. This includes the location of the final
SM/SP during final grading.
Silt Fence (SF)
Silt Fence is a sediment-trapping device as described in the MHFD criteria. Silt fence is
to be inspected and repaired/replaced as necessary. Silt fence will only be used for
stockpile protection for this Project because natural berms will prohibit sediment-laden
runoff from exiting the site.
Street Sweeping and Vacuuming (SS)
Street sweeping is required when sediment has migrated onto paved surfaces. This is to
be done in a timely manner either by hand or street sweeper at a minimum of one time
per week. Flushing of sediment with water is prohibited. State expectation is that this can
be done at the end of the day especially during wet conditions.
18
Surface Roughening (SR)
Any disturbed areas which have not reached final stabilization within two weeks of being
disturbed shall receive surface roughening.
Rock/Curb Socks (RS/CS)
A rock sock is constructed of gravel that has been wrapped by wire mesh or a geotextile
to form an elongated cylindrical filter. Rock socks are typically used either as a perimeter
control or as part of inlet protection. When placed at 45 degree angles and abut the curb
for at least a foot along the down stream side of the curb, rock socks are typically referred
to as curb socks. Rock socks are intended to trap sediment from stormwater runoff that
flows onto roadways as a result of construction activities.
Inlet Protection (IP)
Inlet protection shall be used at all of the locations shown on the approved SWMP plans.
Inlet protection for proposed inlets should be installed immediately after proposed inlet
installation. Inlet protection is to be inspected and repaired/replaced as necessary. Inlet
protection shall be accompanied with a bollard or other traffic delineating device to
prevent being ran over or plowed in high traffic roads.
MATERIAL HANDLING AND SPILL PREVENTION
If a spill should occur, the City of Fort Collins (970)-221-6700, and the Colorado
Department of Public Health and Environment (877)-518-5608) must be notified.
The contractor shall keep specific procedure manuals for material handling information,
accident procedures, and spill handling. At a minimum, the contractor shall adhere to the
following:
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Material and Equipment Storage:
Nonhazardous materials that are to be stockpiled on the site but not installed within 14
days of arrival shall be stored in the construction staging and/or material storage area.
Materials delivered to the site which will be installed within 14 days of arrival may be
stored nearer to the point of installation. These materials include but are not limited to
pipe, precast structures, fire hydrants, tees, valves, and misc. fittings. Construction and
maintenance equipment such as hand tools and small parts shall be stored within the
stabilized storage area or materials storage area in watertight containers. Hazardous
materials that are to be stored on-site such as, but not limited to, oil filters, petroleum
products, paint, and equipment maintenance fluids shall be stored in structurally sound
and sealed containers clearly marked “Hazardous Material”. These containers are to be
located within the stabilized storage areas and/or material storage area.
Spill Response/Management of Contaminated Soils:
• Containment and cleanup of spills should begin promptly after the spill is
observed
• Contain medium sized spills with absorbents (e.g., kitty litter, saw dust)
and use inflatable berms or absorbent snakes as temporary booms for the
spill. Store and dispose of absorbents properly.
• For large spills, first contain the spill and plug storm drain inlets where the
liquid may migrate off-site, then clean up the spill.
• Excavation of spill areas to removed contaminated material may be
required where large spills occur on unpaved surfaces.
• Contain the entire spill if possible. If immediate containment is not
possible, use curbing to route spilled material to a collection basin. The
containment area must have an impermeable surface.
• Material from the spill area must be disposed of or recycled according to
local, state, and federal standards.
20
Vehicle and Equipment Fueling and Maintenance:
The fueling of vehicles and equipment which occurs on-site shall occur in the stabilized
storage area. Only minor equipment maintenance shall occur on-site. All major
equipment maintenance shall be performed off-site. Any equipment fluids generated from
maintenance activities will be disposed of into designated drums stored on spill pallets.
Absorbent, spill-cleanup materials and spill kits shall be available at the stabilized storage
area and/or materials storage area. Drip pans shall be placed under all equipment
receiving maintenance. Drip pans shall also be placed under vehicles and/or equipment
parked overnight which have known fluid leaks.
Waste Management and Disposal, Including Concrete Washout:
All hazardous waste materials shall be disposed of in structurally sound and sealed
containers located within a hazardous materials storage area in the stabilized storage area.
Hazardous waste materials will be stored in appropriate and clearly marked containers
and segregated from other non-waste materials. Secondary containment shall be
provided for all waste materials in the hazardous materials storage area and will consist
of commercially available spill pallets. Additionally, all hazardous waste materials shall
be disposed of in accordance with federal, state, and municipal regulations. Non-
hazardous waste materials may be disposed of into on-site dumpsters. Construction trash
dumpsters should be located in the stabilized storage area. Dumpsters should have a
secure lid and meet all federal, state, and municipal regulations. Only trash and
construction debris from the site should be deposited in these dumpster. No construction
materials shall be buried on-site.
All construction personnel shall be instructed regarding the correct disposal of trash and
construction debris, as well as procedures for hazardous waste disposal. The SWMP
Administrator shall be responsible for seeing that these practices are followed.
21
E. INSTALLATION AND REMOVAL SEQUENCE OF
CONSTRUCTION MEASURES
GENERAL
• Good Housekeeping
• Material Handling and Spill Prevention
INITIAL
Refer to sheet C2.2-2.5, C2.20-2.23, and R2.2-2.4
Prior to Asphalt Demolition, Clear and Grub
• Install Construction Fence
• Install Silt Fence
During and immediately following Asphalt Demolition, Clear and Grub
• Install VTC (VTC shall be installed as soon as possible during
demolition. Limit site access until VTC is in place. Construction fence
around VTC should limit access to site through the VTC only
• Install Stabilized Staging Area (Install construction trailer, stake portable
toilets, and lay down dumpsters as needed)
• Limit disturbance to those areas planned for disturbance and protect
undisturbed areas within the site with construction fence, flagging, etc.
• Sweep or Vacuum sediment as needed.
Maintenance
• Inspect all BMP’s after every precipitation event, and at a minimum of
once per week
• Replace/repair BMP’s as necessary
• Check for sediment deposition on streets and sweep daily
22
INTERIM
Refer to sheet C2.6-2.9 and R2.5-2.7
During Site Grading
• Install temporary drainage ditches
• Install check dams
• Implement stockpile management
• Install sediment basins where the future detention ponds will be
• Install Silt Fence around stockpiles
• Stockpiles shall be no higher than ten feet
• Water the site as needed to prevent dust erosion from wind and
loading/unloading operations. Do not water to the point that runoff is
created.
• Implement Surface Roughening and/or Temporary Seeding as required
During Utility installation
• Install inlet protection immediately after inlets are installed
• Concrete washout areas as needed
During Vertical Construction
• Concrete washout areas as needed
• Implement materials management and good housekeeping practices
During Paving/Concrete Installation
• Concrete Washout Areas as needed for concrete paving
Maintenance
• Inspect all BMP’s after every precipitation event, and at a minimum of
once per week
• Replace/repair BMP’s as necessary
• Check for sediment deposition on streets and sweep daily
• Dispose of Concrete Washout Areas in a timely fashion.
23
• Update Erosion Control Plans to reflect current locations of major
BMP’s including SSA, CWA, and SP
FINAL
Refer to sheet C2.10-2.13, C2.24-2.27, and R2.8-2.10
• Install permanent seeding in landscaped areas shown on the plans
• Do not remove BMP’s until final stabilization is achieved
• In landscaped areas, individual plant density of at least 70% is required
• Implement stockpile management if necessary for final grading. Redline
location on approved plan in construction trailer.
Maintenance
• Inspect all BMP’s after every precipitation event, and at a minimum of
once per week
• Replace/repair BMP’s as necessary
• Check for sediment deposition on streets and sweep daily
• Dispose of Concrete Washout Areas in a timely fashion.
F. PHASING
Montava Phase G is a singular phase in the much larger Montava Development Project.
The limits of Phase G can be viewed on the Erosion Control Plans in Appendix G.
G. MAINTENANCE AND INSPECTION
REQUIREMENTS
The erosion and sediment control measures shall be inspected by the contractor and
evaluated continually throughout the construction period. Inspections shall be performed
either weekly, or every 14 days and after all storm events, and can switch back and forth
as needed. If construction activities have been completed, but final stabilization has not
yet been achieved, the frequency of inspections may be reduced to once every thirty (30)
days.
24
Inspections shall be conducted, and findings documented pursuant to the State Permit.
Inspections shall be recorded on an inspection form acceptable to both the State of
Colorado and the City of Fort Collins. See the Appendix for a sample inspection form.
Inspections shall ensure adherence to all state and local jurisdictional requirements.
Inspections shall also ensure compliance with the erosion control measures stipulated in
this report. Lost or damaged erosion and sediment control devices shall be noted in the
inspection report and shall be repaired or replaced in a timely manner, but in no case
more than seven (7) days after the inspection. Ineffective or inadequate devices shall also
be noted in the inspection report and should be modified or replaced with an adequate
device. Replacement and/or modification of ineffective or inadequate devices shall be
completed in a timely manner, but in no case more than seven (7) days after the
inspection. Any observed differences or modifications to the SWMP made after an
inspection shall be shown on an updated SWMP in a timely manner.
Any reports of non-compliance and/or violations shall be recorded. A brief explanation
shall detail how the instance of non-compliance and/or violation was rectified, and how
future violations will be avoided. The report shall then be signed indicating that site is
once again in compliance by both the individual performing the inspection and the
SWMP administrator.
The permit operator shall keep a record of all inspections on-site with the SWMP Plan.
These records shall be made available to the City of Fort Collins or other authorities
having jurisdiction upon request.
Wherever inspection requirements differ between governing jurisdictions and/or this
SWMP, the more stringent requirements shall apply.
H. FINAL VEGETATION AND STABILIZATION
Exposed dirt in areas that contain hardscapes, buildings, and rock beds will be considered
to be stabilized immediately upon installation. Areas where sod will be installed as per
design, will require soil amending in accordance with §12-132 and irrigated as a
permanent feature to the project. Upon installation of those sod areas they will be
25
considered stabilized. All areas to be seeded as outlined in the Final Landscape Plan or
required by the City in the disturbance of other properties, will have the areas amended in
accordance with §12-132 of City Municipal Code and be seeded based upon the specs
called out in the landscape plan. All seeded areas will be crimped and mulched same day
or next day after seeding in accordance with the Temporary and Permanent Seeding
Details associated with this project as seen in the appendix, and in accordance with the
City of Fort Collins Erosion Control Criteria. Once installed there will be a temporary
irrigation system and all seeding will be monitored until the site has reached a vegetative
cover (density) of 70%. At the point the vegetation has reached 70% density, and
confirmed by the City of Fort Collins, all stormwater infrastructure will be cleaned and
removed of any sediment deposits, and any remaining temporary Control Measures will
be removed.
Anticipated Start of Planting and Seeding: Fall 2024
Anticipated End of Planting and Seeding: Spring 2025
Anticipated Stabilization Date: Spring 2028
SOIL AMMENDMENTS
Topsoil is to be stockpiled and reused. The majority of the site will be temporary, dryland
seed area and will not require soil preparation. As lots are developed in the future, they
must be permanently seeded. All planted/irrigated areas will require soil prep at 3 cubic
yards/ 1,000 square feet. Soil amendment cost is included in the erosion control cost
estimate as part of the landscaping estimate.
PERMANENT SEED MIX
• Reference the final accepted Landscape Plan for the final seed mix.
• All materials furnished shall be free of Colorado State noxious weeds as defined
in Article III, Section 21-40 of the Code of the City of Fort Collins.
26
I. REFERENCES
1. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Rev. December
2018.
2. Colorado Department of Public Health and Environment, Water Quality Control
Division – Stormwater Program, “Stormwater Discharges Associated with
Construction Activity, Stormwater Management Plan Guidance”, revised January
2021.
3. Urban Storm Drainage Criteria Manual, Volume 1, Mile High Flood District, Rev.
August 2018.
4. Urban Storm Drainage Criteria Manual, Volume 2, Mile High Flood District, Rev.
September 2017.
5. Urban Storm Drainage Criteria Manual, Volume 3, Mile High Flood District, Rev.
November 2010 with some sections updated January 2021.
26
Appendix A
Vicinity Map
27
Appendix B
Sample Inspection Forms
28
Appendix C
Engineers Opinion of Probable Cost
-Security Calculation-
ENGINEER'S OPINION OF PROBABLE COST
Project: MONTAVA PHASE G Date: 11-Apr-23
Location: ADDRESS Job No.: 19.1354
Subject: SECURITY CALCULATIONS (IMMEDIATE) Prep. By: TJW
Client: Ckd. By:
Note: Any opinions of price, probable project costs or construction costs rendered by MARTIN/MARTIN represent
its best judgment and are furnished for general guidance. MARTIN/MARTIN makes no warranty of guarantee,
either expressed or implied as to the accuracy of such opinions as compared to bid or actual cost.
Item No. Item Description Units Quantity Unit Price Item Cost
1 Check Dam EA 12 $ 24.00 $ 288.00
2 Concrete Washout Area EA 1 $ 1,000.00 $ 1,000.00
3 Construction Fence LF 2501 $ 5.00 $ 12,505.00
4 Diversion Ditch LF 2020 $ 1.50 $ 3,030.00
5 Inlet Protection EA 101 $ 300.00 $ 30,300.00
6 Outlet Protection EA 2 $ 250.00 $ 500.00
7 Rock Sock LF 0 $ 10.00
8 Rough Cut Street Control (200ft spacing) EA 60 $ 100.00 $ 6,000.00
9 Sediment Basin AC 0 $ 1,000.00
10 Silt Fence LF 2530 $ 2.00 $ 5,060.00
11 Stabilized Staging Area SF 37620 $ 0.25 $ 9,405.00
12 Surface Roughening AC 30.7 $ 600.00 $ 18,420.00
13 VTC EA 1 $ 1,000.00 $ 1,000.00
14 Sediment Control Logs LF 18350 $ 3.00 $ 55,050.00
Remarks: Cost of Items: $ 142,558
50% Contingencies: $ 71,279
$ 26,075.00 Subtotal: $ 213,837
x 1.5: $ 39,112.50
31.18 ACRES @ $2,500 per ACRE
Cost to revegetate is less than total BMP cost,
use BMP cost for required security Total Cost: $ 213,837
Cost to revegetate all disturbed areas:
1
ENGINEER'S OPINION OF PROBABLE COST
Project: MONTAVA PHASE G Date: 11-Apr-23
Location: ADDRESS Job No.: 19.1354
Subject: SECURITY CALCULATIONS (SEEDED) Prep. By: TJW
Client: Ckd. By:
Note: Any opinions of price, probable project costs or construction costs rendered by MARTIN/MARTIN represent
its best judgment and are furnished for general guidance. MARTIN/MARTIN makes no warranty of guarantee,
either expressed or implied as to the accuracy of such opinions as compared to bid or actual cost.
Item No. Item Description Units Quantity Unit Price Item Cost
1 Check Dam EA 9 $ 24.00 $ 216.00
2 Concrete Washout Area EA 0 $ 1,000.00
3 Construction Fence LF 6352 $ 5.00 $ 31,760.00
4 Diversion Ditch LF 1894 $ 1.50 $ 2,841.00
5 Inlet Protection EA 3 $ 300.00 $ 900.00
6 Outlet Protection EA 0 $ 250.00
7 Rock Sock LF 70 $ 10.00 $ 700.00
8 Rough Cut Street Control (200ft spacing) EA 0 $ 100.00
9 Sediment Basin AC 9.26 $ 1,000.00 $ 9,260.00
10 Silt Fence LF 360 $ 2.00 $ 720.00
11 Stabilized Staging Area SF 0 $ 0.25
12 Surface Roughening AC 29.5 $ 600.00 $ 17,700.00
13 VTC EA 0 $ 1,000.00
14 Sediment Control Logs LF 0 $ 3.00
Remarks: Cost of Items: $ 64,097
50% Contingencies: $ 32,049
$ 59,375.00 Subtotal: $ 96,146
x 1.5: $ 89,062.50
23.75 ACRES @ $2,500 per ACRE
Cost to revegetate is less than total BMP cost,
use BMP cost for required security Total Cost: $ 96,146
Cost to revegetate all disturbed areas:
1
ENGINEER'S OPINION OF PROBABLE COST
Project: MONTAVA PHASE G Date: 11-Apr-23
Location: ADDRESS Job No.: 19.1354
Subject: SECURITY CALCULATIONS (OFFSITE BORROW) Prep. By: TJW
Client: Ckd. By:
Note: Any opinions of price, probable project costs or construction costs rendered by MARTIN/MARTIN represent
its best judgment and are furnished for general guidance. MARTIN/MARTIN makes no warranty of guarantee,
either expressed or implied as to the accuracy of such opinions as compared to bid or actual cost.
Item No. Item Description Units Quantity Unit Price Item Cost
1 Check Dam EA 0 $ 24.00
2 Concrete Washout Area EA 0 $ 1,000.00
3 Construction Fence LF 4427 $ 5.00 $ 22,135.00
4 Diversion Ditch LF 0 $ 1.50
5 Inlet Protection EA 0 $ 300.00
6 Outlet Protection EA 0 $ 250.00
7 Rock Sock LF 0 $ 10.00
8 Rough Cut Street Control (200ft spacing) EA 0 $ 100.00
9 Sediment Basin AC 0 $ 1,000.00
10 Silt Fence LF 0 $ 2.00
11 Stabilized Staging Area SF 0 $ 0.25
12 Surface Roughening AC 39.3 $ 600.00 $ 23,580.00
13 VTC EA 0 $ 1,000.00
14 Sediment Control Logs LF 0 $ 3.00
Remarks: Cost of Items: $ 45,715
50% Contingencies: $ 22,858
$ 97,250.00 Subtotal: $ 68,573
x 1.5: $ 145,875.00
38.9 ACRES @ $2,500 per ACRE
Cost to revegetate is more than total BMP cost,
use revegetation cost for required security Total Cost: $ 145,875
Cost to revegetate all disturbed areas:
1
ENGINEER'S OPINION OF PROBABLE COST
Project: MONTAVA PHASE G Date: 11-Apr-23
Location: ADDRESS Job No.: 19.1354
Subject: SECURITY CALCULATIONS (ROADWAY & DITCH) Prep. By: TJW
Client: Ckd. By:
Note: Any opinions of price, probable project costs or construction costs rendered by MARTIN/MARTIN represent
its best judgment and are furnished for general guidance. MARTIN/MARTIN makes no warranty of guarantee,
either expressed or implied as to the accuracy of such opinions as compared to bid or actual cost.
Item No. Item Description Units Quantity Unit Price Item Cost
1 Check Dam EA 0 $ 24.00
2 Concrete Washout Area EA 1 $ 1,000.00 $ 1,000.00
3 Construction Fence LF 775 $ 5.00 $ 3,875.00
4 Diversion Ditch LF 0 $ 1.50
5 Inlet Protection EA 29 $ 300.00 $ 8,700.00
6 Outlet Protection EA 3 $ 250.00 $ 750.00
7 Rock Sock LF 0 $ 10.00
8 Rough Cut Street Control (200ft spacing) EA 0 $ 100.00
9 Sediment Basin AC 0 $ 1,000.00
10 Silt Fence LF 7950 $ 2.00 $ 15,900.00
11 Stabilized Staging Area SF 36470 $ 0.25 $ 9,117.50
12 Surface Roughening AC 19.2 $ 600.00 $ 11,520.00
13 VTC EA 1 $ 1,000.00 $ 1,000.00
14 Sediment Control Logs LF 0 $ 3.00
Remarks: Cost of Items: $ 51,863
50% Contingencies: $ 25,931
$ 97,250.00 Subtotal: $ 77,794
x 1.5: $ 145,875.00
38.9 ACRES @ $2,500 per ACRE
Cost to revegetate is more than total BMP cost,
use revegetation cost for required security Total Cost: $ 145,875
Cost to revegetate all disturbed areas:
1
29
Appendix D
BMP Information
Surface Roughening (SR) EC-1
November 2010 Urban Drainage and Flood Control District SR-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SR-1. Surface roughening via imprinting for temporary
stabilization.
Description
Surface roughening is an erosion control
practice that involves tracking,
scarifying, imprinting, or tilling a
disturbed area to provide temporary
stabilization of disturbed areas. Surface
roughening creates variations in the soil
surface that help to minimize wind and
water erosion. Depending on the
technique used, surface roughening may
also help establish conditions favorable
to establishment of vegetation.
Appropriate Uses
Surface roughening can be used to
provide temporary stabilization of
disturbed areas, such as when
revegetation cannot be immediately established due to seasonal planting limitations. Surface roughening
is not a stand-alone BMP, and should be used in conjunction with other erosion and sediment controls.
Surface roughening is often implemented in conjunction with grading and is typically performed using
heavy construction equipment to track the surface. Be aware that tracking with heavy equipment will also
compact soils, which is not desirable in areas that will be revegetated. Scarifying, tilling, or ripping are
better surface roughening techniques in locations where revegetation is planned. Roughening is not
effective in very sandy soils and cannot be effectively performed in rocky soil.
Design and Installation
Typical design details for surfacing roughening on steep and mild slopes are provided in Details SR-1 and
SR-2, respectively.
Surface roughening should be performed either after final grading or to temporarily stabilize an area
during active construction that may be inactive for a short time period. Surface roughening should create
depressions 2 to 6 inches deep and approximately 6 inches apart. The surface of exposed soil can be
roughened by a number of techniques and equipment. Horizontal grooves (running parallel to the
contours of the land) can be made using tracks from equipment treads, stair-step grading, ripping, or
tilling.
Fill slopes can be constructed with a roughened surface. Cut slopes that have been smooth graded can be
roughened as a subsequent operation. Roughening should follow along the contours of the slope. The
tracks left by truck mounted equipment working perpendicular
to the contour can leave acceptable horizontal depressions;
however, the equipment will also compact the soil.
Surface Roughening
Functions
Erosion Control Yes
Sediment Control No
Site/Material Management No
EC-1 Surface Roughening (SR)
SR-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Maintenance and Removal
Care should be taken not to drive vehicles or equipment over areas that have been surface roughened.
Tire tracks will smooth the roughened surface and may cause runoff to collect into rills and gullies.
Because surface roughening is only a temporary control, additional treatments may be necessary to
maintain the soil surface in a roughened condition.
Areas should be inspected for signs of erosion. Surface roughening is a temporary measure, and will not
provide long-term erosion control.
Surface Roughening (SR) EC-1
November 2010 Urban Drainage and Flood Control District SR-3
Urban Storm Drainage Criteria Manual Volume 3
EC-1 Surface Roughening (SR)
SR-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Temporary and Permanent Seeding (TS/PS) EC-2
November 2010 Urban Drainage and Flood Control District TS/PS-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph TS/PS -1. Equipment used to drill seed. Photo courtesy of
Douglas County.
Description
Temporary seeding can be used to
stabilize disturbed areas that will be
inactive for an extended period.
Permanent seeding should be used to
stabilize areas at final grade that will not
be otherwise stabilized. Effective seeding
includes preparation of a seedbed,
selection of an appropriate seed mixture,
proper planting techniques, and protection
of the seeded area with mulch, geotextiles,
or other appropriate measures.
Appropriate Uses
When the soil surface is disturbed and
will remain inactive for an extended
period (typically 30 days or longer),
proactive stabilization measures should be implemented. If the inactive period is short-lived (on the order
of two weeks), techniques such as surface roughening may be appropriate. For longer periods of
inactivity, temporary seeding and mulching can provide effective erosion control. Permanent seeding
should be used on finished areas that have not been otherwise stabilized.
Typically, local governments have their own seed mixes and timelines for seeding. Check jurisdictional
requirements for seeding and temporary stabilization.
Design and Installation
Effective seeding requires proper seedbed preparation, selection of an appropriate seed mixture, use of
appropriate seeding equipment to ensure proper coverage and density, and protection with mulch or fabric
until plants are established.
The USDCM Volume 2 Revegetation Chapter contains detailed seed mix, soil preparations, and seeding
and mulching recommendations that may be referenced to supplement this Fact Sheet.
Drill seeding is the preferred seeding method. Hydroseeding is not recommended except in areas where
steep slopes prevent use of drill seeding equipment, and even in these instances it is preferable to hand
seed and mulch. Some jurisdictions do not allow hydroseeding or hydromulching.
Seedbed Preparation
Prior to seeding, ensure that areas to be revegetated have
soil conditions capable of supporting vegetation. Overlot
grading can result in loss of topsoil, resulting in poor quality
subsoils at the ground surface that have low nutrient value,
little organic matter content, few soil microorganisms,
rooting restrictions, and conditions less conducive to
infiltration of precipitation. As a result, it is typically
necessary to provide stockpiled topsoil, compost, or other
Temporary and Permanent Seeding
Functions
Erosion Control Yes
Sediment Control No
Site/Material Management No
EC-2 Temporary and Permanent Seeding (TS/PS)
TS/PS-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
soil amendments and rototill them into the soil to a depth of 6 inches or more.
Topsoil should be salvaged during grading operations for use and spread on areas to be revegetated later.
Topsoil should be viewed as an important resource to be utilized for vegetation establishment, due to its
water-holding capacity, structure, texture, organic matter content, biological activity, and nutrient content.
The rooting depth of most native grasses in the semi-arid Denver metropolitan area is 6 to 18 inches. At a
minimum, the upper 6 inches of topsoil should be stripped, stockpiled, and ultimately respread across
areas that will be revegetated.
Where topsoil is not available, subsoils should be amended to provide an appropriate plant-growth
medium. Organic matter, such as well digested compost, can be added to improve soil characteristics
conducive to plant growth. Other treatments can be used to adjust soil pH conditions when needed. Soil
testing, which is typically inexpensive, should be completed to determine and optimize the types and
amounts of amendments that are required.
If the disturbed ground surface is compacted, rip or rototill the surface prior to placing topsoil. If adding
compost to the existing soil surface, rototilling is necessary. Surface roughening will assist in placement
of a stable topsoil layer on steeper slopes, and allow infiltration and root penetration to greater depth.
Prior to seeding, the soil surface should be rough and the seedbed should be firm, but neither too loose
nor compacted. The upper layer of soil should be in a condition suitable for seeding at the proper depth
and conducive to plant growth. Seed-to-soil contact is the key to good germination.
Seed Mix for Temporary Vegetation
To provide temporary vegetative cover on disturbed areas which will not be paved, built upon, or fully
landscaped or worked for an extended period (typically 30 days or more), plant an annual grass
appropriate for the time of planting and mulch the planted areas. Annual grasses suitable for the Denver
metropolitan area are listed in Table TS/PS-1. These are to be considered only as general
recommendations when specific design guidance for a particular site is not available. Local governments
typically specify seed mixes appropriate for their jurisdiction.
Seed Mix for Permanent Revegetation
To provide vegetative cover on disturbed areas that have reached final grade, a perennial grass mix should
be established. Permanent seeding should be performed promptly (typically within 14 days) after
reaching final grade. Each site will have different characteristics and a landscape professional or the local
jurisdiction should be contacted to determine the most suitable seed mix for a specific site. In lieu of a
specific recommendation, one of the perennial grass mixes appropriate for site conditions and growth
season listed in Table TS/PS-2 can be used. The pure live seed (PLS) rates of application recommended
in these tables are considered to be absolute minimum rates for seed applied using proper drill-seeding
equipment.
If desired for wildlife habitat or landscape diversity, shrubs such as rubber rabbitbrush (Chrysothamnus
nauseosus), fourwing saltbush (Atriplex canescens) and skunkbrush sumac (Rhus trilobata) could be
added to the upland seedmixes at 0.25, 0.5 and 1 pound PLS/acre, respectively. In riparian zones,
planting root stock of such species as American plum (Prunus americana), woods rose (Rosa woodsii),
plains cottonwood (Populus sargentii), and willow (Populus spp.) may be considered. On non-topsoiled
upland sites, a legume such as Ladak alfalfa at 1 pound PLS/acre can be included as a source of nitrogen
for perennial grasses.
Temporary and Permanent Seeding (TS/PS) EC-2
November 2010 Urban Drainage and Flood Control District TS/PS-3
Urban Storm Drainage Criteria Manual Volume 3
Seeding dates for the highest success probability of perennial species along the Front Range are generally
in the spring from April through early May and in the fall after the first of September until the ground
freezes. If the area is irrigated, seeding may occur in summer months, as well. See Table TS/PS-3 for
appropriate seeding dates.
Table TS/PS-1. Minimum Drill Seeding Rates for Various Temporary Annual Grasses
Speciesa
(Common name)
Growth
Seasonb
Pounds of
Pure Live Seed
(PLS)/acrec
Planting
Depth
(inches)
1. Oats Cool 35 - 50 1 - 2
2. Spring wheat Cool 25 - 35 1 - 2
3. Spring barley Cool 25 - 35 1 - 2
4. Annual ryegrass Cool 10 - 15 ½
5. Millet Warm 3 - 15 ½ - ¾
6. Sudangrass Warm 5–10 ½ - ¾
7. Sorghum Warm 5–10 ½ - ¾
8. Winter wheat Cool 20–35 1 - 2
9. Winter barley Cool 20–35 1 - 2
10. Winter rye Cool 20–35 1 - 2
11. Triticale Cool 25–40 1 - 2
a Successful seeding of annual grass resulting in adequate plant growth will
usually produce enough dead-plant residue to provide protection from
wind and water erosion for an additional year. This assumes that the cover
is not disturbed or mowed closer than 8 inches.
Hydraulic seeding may be substituted for drilling only where slopes are
steeper than 3:1 or where access limitations exist. When hydraulic
seeding is used, hydraulic mulching should be applied as a separate
operation, when practical, to prevent the seeds from being encapsulated in
the mulch.
b See Table TS/PS-3 for seeding dates. Irrigation, if consistently applied,
may extend the use of cool season species during the summer months.
c Seeding rates should be doubled if seed is broadcast, or increased by 50
percent if done using a Brillion Drill or by hydraulic seeding.
EC-2 Temporary and Permanent Seeding (TS/PS)
TS/PS-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses
Common
a
Name
Botanical
Name
Growth
Seasonb
Growth
Form
Seeds/
Pound
Pounds of
PLS/acre
Alakali Soil Seed Mix
Alkali sacaton Sporobolus airoides Cool Bunch 1,750,000 0.25
Basin wildrye Elymus cinereus Cool Bunch 165,000 2.5
Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5
Jose tall wheatgrass Agropyron elongatum 'Jose' Cool Bunch 79,000 7.0
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 17.75
Fertile Loamy Soil Seed Mix
Ephriam crested wheatgrass Agropyron cristatum
'Ephriam' Cool Sod 175,000 2.0
Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Sodar streambank wheatgrass Agropyron riparium 'Sodar' Cool Sod 170,000 2.5
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 7.0
Total 15.5
High Water Table Soil Seed Mix
Meadow foxtail Alopecurus pratensis Cool Sod 900,000 0.5
Redtop Agrostis alba Warm Open sod 5,000,000 0.25
Reed canarygrass Phalaris arundinacea Cool Sod 68,000 0.5
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Pathfinder switchgrass Panicum virgatum
'Pathfinder' Warm Sod 389,000 1.0
Alkar tall wheatgrass Agropyron elongatum
'Alkar' Cool Bunch 79,000 5.5
Total 10.75
Transition Turf Seed Mixc
Ruebens Canadian bluegrass Poa compressa 'Ruebens' Cool Sod 2,500,000 0.5
Dural hard fescue Festuca ovina 'duriuscula' Cool Bunch 565,000 1.0
Citation perennial ryegrass Lolium perenne 'Citation' Cool Sod 247,000 3.0
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Total 7.5
Temporary and Permanent Seeding (TS/PS) EC-2
November 2010 Urban Drainage and Flood Control District TS/PS-5
Urban Storm Drainage Criteria Manual Volume 3
Table TS/PS-2. Minimum Drill Seeding Rates for Perennial Grasses (cont.)
Common
Name
Botanical
Name
Growth
Seasonb
Growth
Form
Seeds/
Pound
Pounds of
PLS/acre
Sandy Soil Seed Mix
Blue grama Bouteloua gracilis Warm Sod-forming
bunchgrass 825,000 0.5
Camper little bluestem Schizachyrium scoparium
'Camper' Warm Bunch 240,000 1.0
Prairie sandreed Calamovilfa longifolia Warm Open sod 274,000 1.0
Sand dropseed Sporobolus cryptandrus Cool Bunch 5,298,000 0.25
Vaughn sideoats grama Bouteloua curtipendula
'Vaughn' Warm Sod 191,000 2.0
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 10.25
Heavy Clay, Rocky Foothill Seed Mix
Ephriam crested wheatgrass
d
Agropyron cristatum
'Ephriam' Cool Sod 175,000 1.5
Oahe Intermediate wheatgrass Agropyron intermedium
'Oahe' Cool Sod 115,000 5.5
Vaughn sideoats grama
e
Bouteloua curtipendula
'Vaughn' Warm Sod 191,000 2.0
Lincoln smooth brome Bromus inermis leyss
'Lincoln' Cool Sod 130,000 3.0
Arriba western wheatgrass Agropyron smithii 'Arriba' Cool Sod 110,000 5.5
Total 17.5
a All of the above seeding mixes and rates are based on drill seeding followed by crimped hay or straw mulch. These rates
should be doubled if seed is broadcast and should be increased by 50 percent if the seeding is done using a Brillion Drill or is
applied through hydraulic seeding. Hydraulic seeding may be substituted for drilling only where slopes are steeper than 3:1.
If hydraulic seeding is used, hydraulic mulching should be done as a separate operation.
b
See Table TS/PS-3 for seeding dates.
c
If site is to be irrigated, the transition turf seed rates should be doubled.
d
Crested wheatgrass should not be used on slopes steeper than 6H to 1V.
e
Can substitute 0.5 lbs PLS of blue grama for the 2.0 lbs PLS of Vaughn sideoats grama.
EC-2 Temporary and Permanent Seeding (TS/PS)
TS/PS-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Table TS/PS-3. Seeding Dates for Annual and Perennial Grasses
Annual Grasses
(Numbers in table reference
species in Table TS/PS-1)
Perennial Grasses
Seeding Dates Warm Cool Warm Cool
January 1–March 15
March 16–April 30 4 1,2,3
May 1–May 15 4
May 16–June 30 4,5,6,7
July 1–July 15 5,6,7
July 16–August 31
September 1–September 30 8,9,10,11
October 1–December 31
Mulch
Cover seeded areas with mulch or an appropriate rolled erosion control product to promote establishment
of vegetation. Anchor mulch by crimping, netting or use of a non-toxic tackifier. See the Mulching BMP
Fact Sheet for additional guidance.
Maintenance and Removal
Monitor and observe seeded areas to identify areas of poor growth or areas that fail to germinate. Reseed
and mulch these areas, as needed.
An area that has been permanently seeded should have a good stand of vegetation within one growing
season if irrigated and within three growing seasons without irrigation in Colorado. Reseed portions of
the site that fail to germinate or remain bare after the first growing season.
Seeded areas may require irrigation, particularly during extended dry periods. Targeted weed control may
also be necessary.
Protect seeded areas from construction equipment and vehicle access.
Mulching (MU) EC-4
November 2010 Urban Drainage and Flood Control District MU-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph MU-1. An area that was recently seeded, mulched,
and crimped.
Description
Mulching consists of evenly applying
straw, hay, shredded wood mulch, bark or
compost to disturbed soils and securing
the mulch by crimping, tackifiers, netting
or other measures. Mulching helps reduce
erosion by protecting bare soil from
rainfall impact, increasing infiltration, and
reducing runoff. Although often applied
in conjunction with temporary or
permanent seeding, it can also be used for
temporary stabilization of areas that
cannot be reseeded due to seasonal
constraints.
Mulch can be applied either using
standard mechanical dry application
methods or using hydromulching equipment
that hydraulically applies a slurry of water,
wood fiber mulch, and often a tackifier.
Appropriate Uses
Use mulch in conjunction with seeding to help protect the seedbed and stabilize the soil. Mulch can also
be used as a temporary cover on low to mild slopes to help temporarily stabilize disturbed areas where
growing season constraints prevent effective reseeding. Disturbed areas should be properly mulched and
tacked, or seeded, mulched and tacked promptly after final grade is reached (typically within no longer
than 14 days) on portions of the site not otherwise permanently stabilized.
Standard dry mulching is encouraged in most jurisdictions; however, hydromulching may not be allowed
in certain jurisdictions or may not be allowed near waterways.
Do not apply mulch during windy conditions.
Design and Installation
Prior to mulching, surface-roughen areas by rolling with a crimping or punching type roller or by track
walking. Track walking should only be used where other methods are impractical because track walking
with heavy equipment typically compacts the soil.
A variety of mulches can be used effectively at construction
sites, including the following types:
Mulch
Functions
Erosion Control Yes
Sediment Control Moderate
Site/Material Management No
EC-4 Mulching (MU)
MU-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Clean, weed- and seed-free, long-stemmed grass hay (preferred) or cereal grain straw. Hay is preferred
because it is less susceptible to removal by wind. Mulch should be applied evenly at a rate of 2 tons per
acre and must be tacked or fastened by an approved method suitable for the type of mulch used. At least
50 percent of the grass hay mulch, by weight, should be 10 inches or more in length.
Grass hay mulch must be anchored and not merely placed on the surface. This can be accomplished
mechanically by crimping or with the aid of tackifiers or nets. Anchoring with a crimping implement is
preferred, and is the recommended method for areas flatter than 3:1. Mechanical crimpers must be
capable of tucking the long mulch fibers into the soil to a depth of 3 inches without cutting them. An
agricultural disk, while not an ideal substitute, may work if the disk blades are dull or blunted and set
vertically; however, the frame may have to be weighted to afford proper soil penetration.
On small areas sheltered from the wind and heavy runoff, spraying a tackifier on the mulch is satisfactory
for holding it in place. For steep slopes and special situations where greater control is needed, erosion
control blankets anchored with stakes should be used instead of mulch.
Hydraulic mulching consists of wood cellulose fibers mixed with water and a tackifying agent and should
be applied at a rate of no less than 1,500 pounds per acre (1,425 lbs of fibers mixed with at least 75 lbs of
tackifier) with a hydraulic mulcher. For steeper slopes, up to 2000 pounds per acre may be required for
effective hydroseeding. Hydromulch typically requires up to 24 hours to dry; therefore, it should not be
applied immediately prior to inclement weather. Application to roads, waterways and existing vegetation
should be avoided.
Erosion control mats, blankets, or nets are recommended to help stabilize steep slopes (generally 3:1 and
steeper) and waterways. Depending on the product, these may be used alone or in conjunction with grass
or straw mulch. Normally, use of these products will be restricted to relatively small areas.
Biodegradable mats made of straw and jute, straw-coconut, coconut fiber, or excelsior can be used instead
of mulch. (See the ECM/TRM BMP for more information.)
Some tackifiers or binders may be used to anchor mulch. Check with the local jurisdiction for allowed
tackifiers. Manufacturer's recommendations should be followed at all times. (See the Soil Binder BMP
for more information on general types of tackifiers.)
Rock can also be used as mulch. It provides protection of exposed soils to wind and water erosion and
allows infiltration of precipitation. An aggregate base course can be spread on disturbed areas for
temporary or permanent stabilization. The rock mulch layer should be thick enough to provide full
coverage of exposed soil on the area it is applied.
Maintenance and Removal
After mulching, the bare ground surface should not be more than 10 percent exposed. Reapply mulch, as
needed, to cover bare areas.
Check Dams (CD) EC-12
November 2010 Urban Drainage and Flood Control District CD-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph CD-1. Rock check dams in a roadside ditch. Photo
courtesy of WWE.
Description
Check dams are temporary grade control
structures placed in drainage channels to
limit the erosivity of stormwater by
reducing flow velocity. Check dams are
typically constructed from rock, gravel
bags, sand bags, or sometimes,
proprietary devices. Reinforced check
dams are typically constructed from rock
and wire gabion. Although the primary
function of check dams is to reduce the
velocity of concentrated flows, a
secondary benefit is sediment trapping
upstream of the structure.
Appropriate Uses
Use as a grade control for temporary drainage ditches or swales until final soil stabilization measures are
established upstream and downstream. Check dams can be used on mild or moderately steep slopes.
Check dams may be used under the following conditions:
As temporary grade control facilities along waterways until final stabilization is established.
Along permanent swales that need protection prior to installation of a non-erodible lining.
Along temporary channels, ditches or swales that need protection where construction of a non-
erodible lining is not practicable.
Reinforced check dams should be used in areas subject to high flow velocities.
Design and Installation
Place check dams at regularly spaced intervals along the drainage swale or ditch. Check dams heights
should allow for pools to develop upstream of each check dam, extending to the downstream toe of the
check dam immediately upstream.
When rock is used for the check dam, place rock mechanically or by hand. Do not dump rocks into the
drainage channel. Where multiple check dams are used, the top of the lower dam should be at the same
elevation as the toe of the upper dam.
When reinforced check dams are used, install erosion control fabric under and around the check dam to
prevent erosion on the upstream and downstream sides. Each
section of the dam should be keyed in to reduce the potential
for washout or undermining. A rock apron upstream and
downstream of the dam may be necessary to further control
erosion.
Check Dams
Functions
Erosion Control Yes
Sediment Control Moderate
Site/Material Management No
EC-12 Check Dams (CD)
CD-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Design details with notes are provided for the following types of check dams:
Rock Check Dams (CD-1)
Reinforced Check Dams (CD-2)
Sediment control logs may also be used as check dams; however, silt fence is not appropriate for use as a
check dam. Many jurisdictions also prohibit or discourage use of straw bales for this purpose.
Maintenance and Removal
Replace missing rocks causing voids in the check dam. If gravel bags or sandbags are used, replace or
repair torn or displaced bags.
Remove accumulated sediment, as needed to maintain BMP effectiveness, typically before the sediment
depth upstream of the check dam is within ½ of the crest height. Remove accumulated sediment prior to
mulching, seeding, or chemical soil stabilization. Removed sediment can be incorporated into the
earthwork with approval from the Project Engineer, or disposed of at an alternate location in accordance
with the standard specifications.
Check dams constructed in permanent swales should be removed when perennial grasses have become
established, or immediately prior to installation of a non-erodible lining. All of the rock and accumulated
sediment should be removed, and the area seeded and mulched, or otherwise stabilized.
Check Dams (CD) EC-12
November 2010 Urban Drainage and Flood Control District CD-3
Urban Storm Drainage Criteria Manual Volume 3
EC-12 Check Dams (CD)
CD-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Check Dams (CD) EC-12
November 2010 Urban Drainage and Flood Control District CD-5
Urban Storm Drainage Criteria Manual Volume 3
EC-12 Check Dams (CD)
CD-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Concrete Washout Area (CWA) MM-1
November 2010 Urban Drainage and Flood Control District CWA-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph CWA-1. Example of concrete washout area. Note gravel
tracking pad for access and sign.
Description
Concrete waste management involves
designating and properly managing a
specific area of the construction site as a
concrete washout area. A concrete
washout area can be created using one of
several approaches designed to receive
wash water from washing of tools and
concrete mixer chutes, liquid concrete
waste from dump trucks, mobile batch
mixers, or pump trucks. Three basic
approaches are available: excavation of a
pit in the ground, use of an above ground
storage area, or use of prefabricated haul-
away concrete washout containers.
Surface discharges of concrete washout
water from construction sites are prohibited.
Appropriate Uses
Concrete washout areas must be designated on all sites that will generate concrete wash water or liquid
concrete waste from onsite concrete mixing or concrete delivery.
Because pH is a pollutant of concern for washout activities, when unlined pits are used for concrete
washout, the soil must have adequate buffering capacity to result in protection of state groundwater
standards; otherwise, a liner/containment must be used. The following management practices are
recommended to prevent an impact from unlined pits to groundwater:
The use of the washout site should be temporary (less than 1 year), and
The washout site should be not be located in an area where shallow groundwater may be present, such
as near natural drainages, springs, or wetlands.
Design and Installation
Concrete washout activities must be conducted in a manner that does not contribute pollutants to surface
waters or stormwater runoff. Concrete washout areas may be lined or unlined excavated pits in the
ground, commercially manufactured prefabricated washout containers, or aboveground holding areas
constructed of berms, sandbags or straw bales with a plastic liner.
Although unlined washout areas may be used, lined pits may be required to protect groundwater under
certain conditions.
Do not locate an unlined washout area within 400 feet
of any natural drainage pathway or waterbody or
within 1,000 feet of any wells or drinking water
sources. Even for lined concrete washouts, it is
advisable to locate the facility away from waterbodies
and drainage paths. If site constraints make these
Concrete Washout Area
Functions
Erosion Control No
Sediment Control No
Site/Material Management Yes
MM-1 Concrete Washout Area (CWA)
CWA-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
setbacks infeasible or if highly permeable soils exist in the area, then the pit must be installed with an
impermeable liner (16 mil minimum thickness) or surface storage alternatives using prefabricated
concrete washout devices or a lined aboveground storage area should be used.
Design details with notes are provided in Detail CWA-1 for pits and CWA-2 for aboveground storage
areas. Pre-fabricated concrete washout container information can be obtained from vendors.
Maintenance and Removal
A key consideration for concrete washout areas is to ensure that adequate signage is in place identifying
the location of the washout area. Part of inspecting and maintaining washout areas is ensuring that
adequate signage is provided and in good repair and that the washout area is being used, as opposed to
washout in non-designated areas of the site.
Remove concrete waste in the washout area, as needed to maintain BMP function (typically when filled to
about two-thirds of its capacity). Collect concrete waste and deliver offsite to a designated disposal
location.
Upon termination of use of the washout site, accumulated solid waste, including concrete waste and any
contaminated soils, must be removed from the site to prevent on-site disposal of solid waste. If the wash
water is allowed to evaporate and the concrete hardens, it may be recycled.
Photograph CWA-3. Earthen concrete washout. Photo
courtesy of CDOT.
Photograph CWA-2. Prefabricated concrete washout. Photo
courtesy of CDOT.
Concrete Washout Area (CWA) MM-1
November 2010 Urban Drainage and Flood Control District CWA-3
Urban Storm Drainage Criteria Manual Volume 3
MM-1 Concrete Washout Area (CWA)
CWA-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Stockpile Management (SP) MM-2
November 2010 Urban Drainage and Flood Control District SP-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SP-1. A topsoil stockpile that has been partially
revegetated and is protected by silt fence perimeter control.
Description
Stockpile management includes
measures to minimize erosion and
sediment transport from soil stockpiles.
Appropriate Uses
Stockpile management should be used
when soils or other erodible materials
are stored at the construction site.
Special attention should be given to
stockpiles in close proximity to natural
or manmade storm systems.
Design and Installation
Locate stockpiles away from all drainage system components including storm sewer inlets. Where
practical, choose stockpile locations that that will remain undisturbed for the longest period of time as the
phases of construction progress. Place sediment control BMPs around the perimeter of the stockpile, such
as sediment control logs, rock socks, silt fence, straw bales and sand bags. See Detail SP-1 for guidance
on proper establishment of perimeter controls around a stockpile. For stockpiles in active use, provide a
stabilized designated access point on the upgradient side of the stockpile.
Stabilize the stockpile surface with surface roughening, temporary seeding and mulching, erosion control
blankets, or soil binders. Soils stockpiled for an extended period (typically for more than 60 days) should
be seeded and mulched with a temporary grass cover once the stockpile is placed (typically within 14
days). Use of mulch only or a soil binder is acceptable if the stockpile will be in place for a more limited
time period (typically 30-60 days). Timeframes for stabilization of stockpiles noted in this fact sheet are
"typical" guidelines. Check permit requirements for specific federal, state, and/or local requirements that
may be more prescriptive.
Stockpiles should not be placed in streets or paved areas unless no other practical alternative exists. See
the Stabilized Staging Area Fact Sheet for guidance when staging in roadways is unavoidable due to
space or right-of-way constraints. For paved areas, rock socks must be used for perimeter control and all
inlets with the potential to receive sediment from the stockpile (even from vehicle tracking) must be
protected.
Maintenance and Removal
Inspect perimeter controls and inlet protection in accordance with their respective BMP Fact Sheets.
Where seeding, mulch and/or soil binders are used, reseeding or reapplication of soil binder may be
necessary.
When temporary removal of a perimeter BMP is necessary
to access a stockpile, ensure BMPs are reinstalled in
accordance with their respective design detail section.
Stockpile Management
Functions
Erosion Control Yes
Sediment Control Yes
Site/Material Management Yes
MM-2 Stockpile Management (SM)
SP-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
When the stockpile is no longer needed, properly dispose of excess materials and revegetate or otherwise
stabilize the ground surface where the stockpile was located.
Stockpile Management (SP) MM-2
November 2010 Urban Drainage and Flood Control District SP-3
Urban Storm Drainage Criteria Manual Volume 3
MM-2 Stockpile Management (SM)
SP-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Stockpile Management (SP) MM-2
November 2010 Urban Drainage and Flood Control District SP-5
Urban Storm Drainage Criteria Manual Volume 3
MM-2 Stockpile Management (SM)
SP-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Good Housekeeping Practices (GH) MM-3
November 2010 Urban Drainage and Flood Control District GH-1
Urban Storm Drainage Criteria Manual Volume 3
Photographs GH-1 and GH-2. Proper materials
storage and secondary containment for fuel tanks
are important good housekeeping practices. Photos
courtesy of CDOT and City of Aurora.
Description
Implement construction site good housekeeping practices to
prevent pollution associated with solid, liquid and hazardous
construction-related materials and wastes. Stormwater
Management Plans (SWMPs) should clearly specify BMPs
including these good housekeeping practices:
Provide for waste management.
Establish proper building material staging areas.
Designate paint and concrete washout areas.
Establish proper equipment/vehicle fueling and
maintenance practices.
Control equipment/vehicle washing and allowable non-
stormwater discharges.
Develop a spill prevention and response plan.
Acknowledgement: This Fact Sheet is based directly on
EPA guidance provided in Developing Your Stormwater
Pollution Prevent Plan (EPA 2007).
Appropriate Uses
Good housekeeping practices are necessary at all construction sites.
Design and Installation
The following principles and actions should be addressed in SWMPs:
Provide for Waste Management. Implement management procedures and practices to prevent or
reduce the exposure and transport of pollutants in stormwater from solid, liquid and sanitary wastes
that will be generated at the site. Practices such as trash disposal, recycling, proper material handling,
and cleanup measures can reduce the potential for stormwater runoff to pick up construction site
wastes and discharge them to surface waters. Implement a comprehensive set of waste-management
practices for hazardous or toxic materials, such as paints, solvents, petroleum products, pesticides,
wood preservatives, acids, roofing tar, and other materials. Practices should include storage,
handling, inventory, and cleanup procedures, in case of spills. Specific practices that should be
considered include:
Solid or Construction Waste
o Designate trash and bulk waste-collection areas on-
site.
Good Housekeeping
Functions
Erosion Control No
Sediment Control No
Site/Material Management Yes
MM-3 Good Housekeeping Practices (GH)
GH-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Photograph GH-3. Locate portable toilet facilities on level
surfaces away from waterways and storm drains. Photo
courtesy of WWE.
o Recycle materials whenever possible (e.g., paper, wood, concrete, oil).
o Segregate and provide proper disposal options for hazardous material wastes.
o Clean up litter and debris from the construction site daily.
o Locate waste-collection areas away from streets, gutters, watercourses, and storm drains. Waste-
collection areas (dumpsters, and such) are often best located near construction site entrances to
minimize traffic on disturbed soils. Consider secondary containment around waste collection
areas to minimize the likelihood of contaminated discharges.
o Empty waste containers before they are full and overflowing.
Sanitary and Septic Waste
o Provide convenient, well-maintained, and properly located toilet facilities on-site.
o Locate toilet facilities away from storm drain inlets and waterways to prevent accidental spills
and contamination of stormwater.
o Maintain clean restroom facilities and empty portable toilets regularly.
o Where possible, provide secondary containment pans under portable toilets.
o Provide tie-downs or stake-downs for portable toilets.
o Educate employees, subcontractors, and suppliers on locations of facilities.
o Treat or dispose of sanitary and septic waste in accordance with state or local regulations. Do not
discharge or bury wastewater at the construction site.
o Inspect facilities for leaks. If found, repair or replace immediately.
o Special care is necessary during maintenance (pump out) to ensure that waste and/or biocide are
not spilled on the ground.
Hazardous Materials and Wastes
o Develop and implement employee and
subcontractor education, as needed, on
hazardous and toxic waste handling,
storage, disposal, and cleanup.
o Designate hazardous waste-collection
areas on-site.
o Place all hazardous and toxic material
wastes in secondary containment.
Good Housekeeping Practices (GH) MM-3
November 2010 Urban Drainage and Flood Control District GH-3
Urban Storm Drainage Criteria Manual Volume 3
o Hazardous waste containers should be inspected to ensure that all containers are labeled properly
and that no leaks are present.
Establish Proper Building Material Handling and Staging Areas. The SWMP should include
comprehensive handling and management procedures for building materials, especially those that are
hazardous or toxic. Paints, solvents, pesticides, fuels and oils, other hazardous materials or building
materials that have the potential to contaminate stormwater should be stored indoors or under cover
whenever possible or in areas with secondary containment. Secondary containment measures prevent
a spill from spreading across the site and may include dikes, berms, curbing, or other containment
methods. Secondary containment techniques should also ensure the protection of groundwater.
Designate staging areas for activities such as fueling vehicles, mixing paints, plaster, mortar, and
other potential pollutants. Designated staging areas enable easier monitoring of the use of materials
and clean up of spills. Training employees and subcontractors is essential to the success of this
pollution prevention principle. Consider the following specific materials handling and staging
practices:
o Train employees and subcontractors in proper handling and storage practices.
o Clearly designate site areas for staging and storage with signs and on construction drawings.
Staging areas should be located in areas central to the construction site. Segment the staging area
into sub-areas designated for vehicles, equipment, or stockpiles. Construction entrances and exits
should be clearly marked so that delivery vehicles enter/exit through stabilized areas with vehicle
tracking controls (See Vehicle Tracking Control Fact Sheet).
o Provide storage in accordance with Spill Protection, Control and Countermeasures (SPCC)
requirements and plans and provide cover and impermeable perimeter control, as necessary, for
hazardous materials and contaminated soils that must be stored on site.
o Ensure that storage containers are regularly inspected for leaks, corrosion, support or foundation
failure, or other signs of deterioration and tested for soundness.
o Reuse and recycle construction materials when possible.
Designate Concrete Washout Areas. Concrete contractors should be encouraged to use the washout
facilities at their own plants or dispatch facilities when feasible; however, concrete washout
commonly occurs on construction sites. If it is necessary to provide for concrete washout areas on-
site, designate specific washout areas and design facilities to handle anticipated washout water.
Washout areas should also be provided for paint and stucco operations. Because washout areas can
be a source of pollutants from leaks or spills, care must be taken with regard to their placement and
proper use. See the Concrete Washout Area Fact Sheet for detailed guidance.
Both self-constructed and prefabricated washout containers can fill up quickly when concrete, paint,
and stucco work are occurring on large portions of the site. Be sure to check for evidence that
contractors are using the washout areas and not dumping materials onto the ground or into drainage
facilities. If the washout areas are not being used regularly, consider posting additional signage,
relocating the facilities to more convenient locations, or providing training to workers and
contractors.
When concrete, paint, or stucco is part of the construction process, consider these practices which will
help prevent contamination of stormwater. Include the locations of these areas and the maintenance
and inspection procedures in the SWMP.
MM-3 Good Housekeeping Practices (GH)
GH-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
o Do not washout concrete trucks or equipment into storm drains, streets, gutters, uncontained
areas, or streams. Only use designated washout areas.
o Establish washout areas and advertise their locations with signs. Ensure that signage remains in
good repair.
o Provide adequate containment for the amount of wash water that will be used.
o Inspect washout structures daily to detect leaks or tears and to identify when materials need to be
removed.
o Dispose of materials properly. The preferred method is to allow the water to evaporate and to
recycle the hardened concrete. Full service companies may provide dewatering services and
should dispose of wastewater properly. Concrete wash water can be highly polluted. It should
not be discharged to any surface water, storm sewer system, or allowed to infiltrate into the
ground in the vicinity of waterbodies. Washwater should not be discharged to a sanitary sewer
system without first receiving written permission from the system operator.
Establish Proper Equipment/Vehicle Fueling and Maintenance Practices. Create a clearly
designated on-site fueling and maintenance area that is clean and dry. The on-site fueling area should
have a spill kit, and staff should know how to use it. If possible, conduct vehicle fueling and
maintenance activities in a covered area. Consider the following practices to help prevent the
discharge of pollutants to stormwater from equipment/vehicle fueling and maintenance. Include the
locations of designated fueling and maintenance areas and inspection and maintenance procedures in
the SWMP.
o Train employees and subcontractors in proper fueling procedures (stay with vehicles during
fueling, proper use of pumps, emergency shutoff valves, etc.).
o Inspect on-site vehicles and equipment regularly for leaks, equipment damage, and other service
problems.
o Clearly designate vehicle/equipment service areas away from drainage facilities and watercourses
to prevent stormwater run-on and runoff.
o Use drip pans, drip cloths, or absorbent pads when replacing spent fluids.
o Collect all spent fluids, store in appropriate labeled containers in the proper storage areas, and
recycle fluids whenever possible.
Control Equipment/Vehicle Washing and Allowable Non-Stormwater Discharges. Implement
practices to prevent contamination of surface and groundwater from equipment and vehicle wash
water. Representative practices include:
o Educate employees and subcontractors on proper washing procedures.
o Use off-site washing facilities, when available.
o Clearly mark the washing areas and inform workers that all washing must occur in this area.
o Contain wash water and treat it using BMPs. Infiltrate washwater when possible, but maintain
separation from drainage paths and waterbodies.
Good Housekeeping Practices (GH) MM-3
November 2010 Urban Drainage and Flood Control District GH-5
Urban Storm Drainage Criteria Manual Volume 3
o Use high-pressure water spray at vehicle washing facilities without detergents. Water alone can
remove most dirt adequately.
o Do not conduct other activities, such as vehicle repairs, in the wash area.
o Include the location of the washing facilities and the inspection and maintenance procedures in
the SWMP.
Develop a Spill Prevention and Response Plan. Spill prevention and response procedures must be
identified in the SWMP. Representative procedures include identifying ways to reduce the chance of
spills, stop the source of spills, contain and clean up spills, dispose of materials contaminated by
spills, and train personnel responsible for spill prevention and response. The plan should also specify
material handling procedures and storage requirements and ensure that clear and concise spill cleanup
procedures are provided and posted for areas in which spills may potentially occur. When developing
a spill prevention plan, include the following:
o Note the locations of chemical storage areas, storm drains, tributary drainage areas, surface
waterbodies on or near the site, and measures to stop spills from leaving the site.
o Provide proper handling and safety procedures for each type of waste. Keep Material Safety Data
Sheets (MSDSs) for chemical used on site with the SWMP.
o Establish an education program for employees and subcontractors on the potential hazards to
humans and the environment from spills and leaks.
o Specify how to notify appropriate authorities, such as police and fire departments, hospitals, or
municipal sewage treatment facilities to request assistance. Emergency procedures and contact
numbers should be provided in the SWMP and posted at storage locations.
o Describe the procedures, equipment and materials for immediate cleanup of spills and proper
disposal.
o Identify personnel responsible for implementing the plan in the event of a spill. Update the spill
prevention plan and clean up materials as changes occur to the types of chemicals stored and used
at the facility.
MM-3 Good Housekeeping Practices (GH)
GH-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Spill Prevention, Control, and Countermeasure (SPCC) Plan
Construction sites may be subject to 40 CFR Part 112 regulations that require the preparation and
implementation of a SPCC Plan to prevent oil spills from aboveground and underground storage tanks.
The facility is subject to this rule if it is a non-transportation-related facility that:
Has a total storage capacity greater than 1,320 gallons or a completely buried storage capacity
greater than 42,000 gallons.
Could reasonably be expected to discharge oil in quantities that may be harmful to navigable waters
of the United States and adjoining shorelines.
Furthermore, if the facility is subject to 40 CFR Part 112, the SWMP should reference the SPCC Plan.
To find out more about SPCC Plans, see EPA's website on SPPC at www.epa.gov/oilspill/spcc.htm.
Reporting Oil Spills
In the event of an oil spill, contact the National Response Center toll free at 1-800-424- 8802 for
assistance, or for more details, visit their website: www.nrc.uscg.mil.
Maintenance and Removal
Effective implementation of good housekeeping practices is dependent on clear designation of personnel
responsible for supervising and implementing good housekeeping programs, such as site cleanup and
disposal of trash and debris, hazardous material management and disposal, vehicle and equipment
maintenance, and other practices. Emergency response "drills" may aid in emergency preparedness.
Checklists may be helpful in good housekeeping efforts.
Staging and storage areas require permanent stabilization when the areas are no longer being used for
construction-related activities.
Construction-related materials, debris and waste must be removed from the construction site once
construction is complete.
Design Details
See the following Fact Sheets for related Design Details:
MM-1 Concrete Washout Area
MM-2 Stockpile Management
SM-4 Vehicle Tracking Control
Design details are not necessary for other good housekeeping practices; however, be sure to designate
where specific practices will occur on the appropriate construction drawings.
Silt Fence (SF) SC-1
November 2010 Urban Drainage and Flood Control District SF-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SF-1. Silt fence creates a sediment barrier, forcing
sheet flow runoff to evaporate or infiltrate.
Description
A silt fence is a woven geotextile fabric
attached to wooden posts and trenched
into the ground. It is designed as a
sediment barrier to intercept sheet flow
runoff from disturbed areas.
Appropriate Uses
A silt fence can be used where runoff is
conveyed from a disturbed area as sheet
flow. Silt fence is not designed to
receive concentrated flow or to be used
as a filter fabric. Typical uses include:
Down slope of a disturbed area to
accept sheet flow.
Along the perimeter of a receiving
water such as a stream, pond or
wetland.
At the perimeter of a construction site.
Design and Installation
Silt fence should be installed along the contour of slopes so that it intercepts sheet flow. The maximum
recommended tributary drainage area per 100 lineal feet of silt fence, installed along the contour, is
approximately 0.25 acres with a disturbed slope length of up to 150 feet and a tributary slope gradient no
steeper than 3:1. Longer and steeper slopes require additional measures. This recommendation only
applies to silt fence installed along the contour. Silt fence installed for other uses, such as perimeter
control, should be installed in a way that will not produce concentrated flows. For example, a "J-hook"
installation may be appropriate to force runoff to pond and evaporate or infiltrate in multiple areas rather
than concentrate and cause erosive conditions parallel to the silt fence.
See Detail SF-1 for proper silt fence installation, which involves proper trenching, staking, securing the
fabric to the stakes, and backfilling the silt fence. Properly installed silt fence should not be easily pulled
out by hand and there should be no gaps between the ground and the fabric.
Silt fence must meet the minimum allowable strength requirements, depth of installation requirement, and
other specifications in the design details. Improper installation
of silt fence is a common reason for silt fence failure; however,
when properly installed and used for the appropriate purposes, it
can be highly effective.
Silt Fence
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management No
SC-1 Silt Fence (SF)
SF-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Photograph SF-2. When silt fence is not installed along
the contour, a "J-hook" installation may be appropriate
to ensure that the BMP does not create concentrated
flow parallel to the silt fence. Photo courtesy of Tom
Gore.
Maintenance and Removal
Inspection of silt fence includes observing the
material for tears or holes and checking for slumping
fence and undercut areas bypassing flows. Repair of
silt fence typically involves replacing the damaged
section with a new section. Sediment accumulated
behind silt fence should be removed, as needed to
maintain BMP effectiveness, typically before it
reaches a depth of 6 inches.
Silt fence may be removed when the upstream area
has reached final stabilization.
Silt Fence (SF) SC-1
November 2010 Urban Drainage and Flood Control District SF-3
Urban Storm Drainage Criteria Manual Volume 3
SC-1 Silt Fence (SF)
SF-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Inlet Protection (IP) SC-6
November 2010 Urban Drainage and Flood Control District IP-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph IP-1. Inlet protection for a curb opening inlet.
Description
Inlet protection consists of permeable
barriers installed around an inlet to
filter runoff and remove sediment prior
to entering a storm drain inlet. Inlet
protection can be constructed from rock
socks, sediment control logs, silt fence,
block and rock socks, or other materials
approved by the local jurisdiction.
Area inlets can also be protected by
over-excavating around the inlet to
form a sediment trap.
Appropriate Uses
Install protection at storm sewer inlets
that are operable during construction.
Consider the potential for tracked-out
sediment or temporary stockpile areas to contribute sediment to inlets when determining which inlets
must be protected. This may include inlets in the general proximity of the construction area, not limited
to downgradient inlets. Inlet protection is not
Design and Installation
a stand-alone BMP and should be used in conjunction with
other upgradient BMPs.
To function effectively, inlet protection measures must be installed to ensure that flows do not bypass the
inlet protection and enter the storm drain without treatment. However, designs must also enable the inlet
to function without completely blocking flows into the inlet in a manner that causes localized flooding.
When selecting the type of inlet protection, consider factors such as type of inlet (e.g., curb or area, sump
or on-grade conditions), traffic, anticipated flows, ability to secure the BMP properly, safety and other
site-specific conditions. For example, block and rock socks will be better suited to a curb and gutter
along a roadway, as opposed to silt fence or sediment control logs, which cannot be properly secured in a
curb and gutter setting, but are effective area inlet protection measures.
Several inlet protection designs are provided in the Design Details. Additionally, a variety of proprietary
products are available for inlet protection that may be approved for use by local governments. If
proprietary products are used, design details and installation procedures from the manufacturer must be
followed. Regardless of the type of inlet protection selected, inlet protection is most effective when
combined with other BMPs such as curb socks and check dams. Inlet protection is often the last barrier
before runoff enters the storm sewer or receiving water.
Design details with notes are provided for these forms of inlet
protection:
IP-1. Block and Rock Sock Inlet Protection for Sump or On-grade
Inlets
IP-2. Curb (Rock) Socks Upstream of Inlet Protection, On-grade
Inlets
Inlet Protection
(various forms)
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management No
SC-6 Inlet Protection (IP)
IP-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
IP-3. Rock Sock Inlet Protection for Sump/Area Inlet
IP-4. Silt Fence Inlet Protection for Sump/Area Inlet
IP-5. Over-excavation Inlet Protection
IP-6. Straw Bale Inlet Protection for Sump/Area Inlet
CIP-1. Culvert Inlet Protection
Propriety inlet protection devices should be installed in accordance with manufacturer specifications.
More information is provided below on selecting inlet protection for sump and on-grade locations.
Inlets Located in a Sump
When applying inlet protection in sump conditions, it is important that the inlet continue to function
during larger runoff events. For curb inlets, the maximum height of the protective barrier should be lower
than the top of the curb opening to allow overflow into the inlet during larger storms without excessive
localized flooding. If the inlet protection height is greater than the curb elevation, particularly if the filter
becomes clogged with sediment, runoff will not enter the inlet and may bypass it, possibly causing
localized flooding, public safety issues, and downstream erosion and damage from bypassed flows.
Area inlets located in a sump setting can be protected through the use of silt fence, concrete block and
rock socks (on paved surfaces), sediment control logs/straw wattles embedded in the adjacent soil and
stacked around the area inlet (on pervious surfaces), over-excavation around the inlet, and proprietary
products providing equivalent functions.
Inlets Located on a Slope
For curb and gutter inlets on paved sloping streets, block and rock sock inlet protection is recommended
in conjunction with curb socks in the gutter leading to the inlet. For inlets located along unpaved roads,
also see the Check Dam Fact Sheet.
Maintenance and Removal
Inspect inlet protection frequently. Inspection and maintenance guidance includes:
Inspect for tears that can result in sediment directly entering the inlet, as well as result in the contents
of the BMP (e.g., gravel) washing into the inlet.
Check for improper installation resulting in untreated flows bypassing the BMP and directly entering
the inlet or bypassing to an unprotected downstream inlet. For example, silt fence that has not been
properly trenched around the inlet can result in flows under the silt fence and directly into the inlet.
Look for displaced BMPs that are no longer protecting the inlet. Displacement may occur following
larger storm events that wash away or reposition the inlet protection. Traffic or equipment may also
crush or displace the BMP.
Monitor sediment accumulation upgradient of the inlet protection.
Inlet Protection (IP) SC-6
November 2010 Urban Drainage and Flood Control District IP-3
Urban Storm Drainage Criteria Manual Volume 3
Remove sediment accumulation from the area upstream of the inlet protection, as needed to maintain
BMP effectiveness, typically when it reaches no more than half the storage capacity of the inlet
protection. For silt fence, remove sediment when it accumulates to a depth of no more than 6 inches.
Remove sediment accumulation from the area upstream of the inlet protection as needed to maintain
the functionality of the BMP.
Propriety inlet protection devices should be inspected and maintained in accordance with
manufacturer specifications. If proprietary inlet insert devices are used, sediment should be removed
in a timely manner to prevent devices from breaking and spilling sediment into the storm drain.
Inlet protection must be removed and properly disposed of when the drainage area for the inlet has
reached final stabilization.
SC-6 Inlet Protection (IP)
IP-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Inlet Protection (IP) SC-6
November 2010 Urban Drainage and Flood Control District IP-5
Urban Storm Drainage Criteria Manual Volume 3
SC-6 Inlet Protection (IP)
IP-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
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Inlet Protection (IP) SC-6
November 2010 Urban Drainage and Flood Control District IP-7
Urban Storm Drainage Criteria Manual Volume 3
Rock Sock (RS) SC-5
November 2010 Urban Drainage and Flood Control District RS-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph RS-1. Rock socks placed at regular intervals in a curb
line can help reduce sediment loading to storm sewer inlets. Rock
socks can also be used as perimeter controls.
Description
A rock sock is constructed of gravel
that has been wrapped by wire mesh or
a geotextile to form an elongated
cylindrical filter. Rock socks are
typically used either as a perimeter
control or as part of inlet protection.
When placed at angles in the curb line,
rock socks are typically referred to as
curb socks. Rock socks are intended to
trap sediment from stormwater runoff
that flows onto roadways as a result of
construction activities.
Appropriate Uses
Rock socks can be used at the perimeter
of a disturbed area to control localized
sediment loading. A benefit of rock
socks as opposed to other perimeter controls is that they do not have to be trenched or staked into the
ground; therefore, they are often used on roadway construction projects where paved surfaces are present.
Use rock socks in inlet protection applications when the construction of a roadway is substantially
complete and the roadway has been directly connected to a receiving storm system.
Design and Installation
When rock socks are used as perimeter controls, the maximum recommended tributary drainage area per
100 lineal feet of rock socks is approximately 0.25 acres with disturbed slope length of up to 150 feet and
a tributary slope gradient no steeper than 3:1. A rock sock design detail and notes are provided in Detail
RS-1. Also see the Inlet Protection Fact Sheet for design and installation guidance when rock socks are
used for inlet protection and in the curb line.
When placed in the gutter adjacent to a curb, rock socks should protrude no more than two feet from the
curb in order for traffic to pass safely. If located in a high traffic area, place construction markers to alert
drivers and street maintenance workers of their presence.
Maintenance and Removal
Rock socks are susceptible to displacement and breaking due to vehicle traffic. Inspect rock socks for
damage and repair or replace as necessary. Remove sediment by sweeping or vacuuming as needed to
maintain the functionality of the BMP, typically when sediment
has accumulated behind the rock sock to one-half of the sock's
height.
Once upstream stabilization is complete, rock socks and
accumulated sediment should be removed and properly disposed.
Rock Sock
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management No
SC-5 Rock Sock (RS)
RS-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Rock Sock (RS) SC-5
November 2010 Urban Drainage and Flood Control District RS-3
Urban Storm Drainage Criteria Manual Volume 3
Sediment Basin (SB) SC-7
November 2010 Urban Drainage and Flood Control District SB-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SB-1. Sediment basin at the toe of a slope. Photo
courtesy of WWE.
Description
A sediment basin is a temporary pond
built on a construction site to capture
eroded or disturbed soil transported in
storm runoff prior to discharge from the
site. Sediment basins are designed to
capture site runoff and slowly release it to
allow time for settling of sediment prior
to discharge. Sediment basins are often
constructed in locations that will later be
modified to serve as post-construction
stormwater basins.
Appropriate Uses
Most large construction sites (typically
greater than 2 acres) will require one or
more sediment basins for effective
management of construction site runoff. On linear construction projects, sediment basins may be
impractical; instead, sediment traps or other combinations of BMPs may be more appropriate.
Sediment basins should not be used as stand-alone sediment controls. Erosion and other sediment
controls should also be implemented upstream.
When feasible, the sediment basin should be installed in the same location where a permanent post-
construction detention pond will be located.
Design and Installation
The design procedure for a sediment basin includes these steps:
Basin Storage Volume: Provide a storage volume of at least 3,600 cubic feet per acre of drainage
area. To the extent practical, undisturbed and/or off-site areas should be diverted around sediment
basins to prevent “clean” runoff from mixing with runoff from disturbed areas. For undisturbed areas
(both on-site and off-site) that cannot be diverted around the sediment basin, provide a minimum of
500 ft3/acre of storage for undeveloped (but stable) off-site areas in addition to the 3,600 ft3/acre for
disturbed areas. For stable, developed areas that cannot be diverted around the sediment basin,
storage volume requirements are summarized in Table SB-1.
Basin Geometry: Design basin with a minimum length-to-width ratio of 2:1 (L:W). If this cannot be
achieved because of site space constraints, baffling may
be required to extend the effective distance between the
inflow point(s) and the outlet to minimize short-circuiting.
Dam Embankment: It is recommended that
embankment slopes be 4:1 (H:V) or flatter and no steeper
than 3:1 (H:V) in any location.
Sediment Basins
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management No
SC-7 Sediment Basin (SB)
SB-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Inflow Structure: For concentrated flow entering the basin, provide energy dissipation at the point
of inflow.
Table SB-1. Additional Volume Requirements for Undisturbed and Developed TributaryAreas
Draining through Sediment Basins
Imperviousness (%)
Additional Storage Volume (ft3)
Per Acre of Tributary Area
Undeveloped 500
10 800
20 1230
30 1600
40 2030
50 2470
60 2980
70 3560
80 4360
90 5300
100 6460
Outlet Works: The outlet pipe shall extend through the embankment at a minimum slope of 0.5
percent. Outlet works can be designed using one of the following approaches:
o Perforated Riser/Plate: Follow the design criteria for Full Spectrum Detention outlets in the
EDB BMP Fact Sheet provided in Chapter 4 of this manual for sizing of outlet perforations with
an emptying time of approximately 72 hours. In lieu of the well-screen trash rack, pack
uniformly sized 1½ - to 2-inch gravel in front of the plate. This gravel will need to be cleaned out
frequently during the construction period as sediment accumulates within it. The gravel pack will
need to be removed and disposed of following construction to reclaim the basin for use as a
permanent detention facility. If the basin will be used as a permanent extended detention basin
for the site, a well-screen trash rack will need to be installed once contributing drainage areas
have been stabilized and the gravel pack and accumulated sediment have been removed.
o Floating Skimmer: If a floating skimmer is used, install it using manufacturer’s
recommendations. Illustration SB-1 provides an illustration of a Faircloth Skimmer Floating
Outlet™, one of the more commonly used floating skimmer outlets. A skimmer should be
designed to release the design volume in no less than 48 hours. The use of a floating skimmer
outlet can increase the sediment capture efficiency of a basin significantly. A floating outlet
continually decants cleanest water off the surface of the pond and releases cleaner water than
would discharge from a perforated riser pipe or plate.
Sediment Basin (SB) SC-7
November 2010 Urban Drainage and Flood Control District SB-3
Urban Storm Drainage Criteria Manual Volume 3
Illustration SB-1. Outlet structure for a temporary sediment basin - Faircloth Skimmer Floating Outlet. Illustration courtesy
of J. W. Faircloth & Sons, Inc., FairclothSkimmer.com.
o Outlet Protection: Outlet protection should be provided where the velocity of flow will exceed
the maximum permissible velocity of the material of the waterway into which discharge occurs.
This may require the use of a riprap apron at the outlet location and/or other measures to keep the
waterway from eroding.
o Emergency Spillway: Provide a stabilized emergency overflow spillway for rainstorms that
exceed the capacity of the sediment basin volume and its outlet. Protect basin embankments from
erosion and overtopping. If the sediment basin will be converted to a permanent detention basin,
design and construct the emergency spillway(s) as required for the permanent facility. If the
sediment basin will not become a permanent detention basin, it may be possible to substitute a
heavy polyvinyl membrane or properly bedded rock cover to line the spillway and downstream
embankment, depending on the height, slope, and width of the embankments.
Maintenance and Removal
Maintenance activities include the following:
• Dredge sediment from the basin, as needed to maintain BMP effectiveness, typically when the design
storage volume is no more than one-third filled with sediment.
• Inspect the sediment basin embankments for stability and seepage.
• Inspect the inlet and outlet of the basin, repair damage, and remove debris. Remove, clean and
replace the gravel around the outlet on a regular basis to remove the accumulated sediment within it
and keep the outlet functioning.
• Be aware that removal of a sediment basin may require dewatering and associated permit
requirements.
• Do not remove a sediment basin until the upstream area has been stabilized with vegetation.
SC-7 Sediment Basin (SB)
SB-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Final disposition of the sediment basin depends on whether the basin will be converted to a permanent
post-construction stormwater basin or whether the basin area will be returned to grade. For basins being
converted to permanent detention basins, remove accumulated sediment and reconfigure the basin and
outlet to meet the requirements of the final design for the detention facility. If the sediment basin is not to
be used as a permanent detention facility, fill the excavated area with soil and stabilize with vegetation.
Sediment Basin (SB) SC-7
November 2010 Urban Drainage and Flood Control District SB-5
Urban Storm Drainage Criteria Manual Volume 3
SC-7 Sediment Basin (SB)
SB-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Sediment Basin (SB) SC-7
November 2010 Urban Drainage and Flood Control District SB-7
Urban Storm Drainage Criteria Manual Volume 3
Construction Fence (CF) SM-3
November 2010 Urban Drainage and Flood Control District CF-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph CF-1. A construction fence helps delineate areas where
existing vegetation is being protected. Photo courtesy of Douglas
County.
Description
A construction fence restricts site access
to designated entrances and exits,
delineates construction site boundaries,
and keeps construction out of sensitive
areas such as natural areas to be
preserved as open space, wetlands and
riparian areas.
Appropriate Uses
A construction fence can be used to
delineate the site perimeter and locations
within the site where access is restricted
to protect natural resources such as
wetlands, waterbodies, trees, and other
natural areas of the site that should not be
disturbed.
If natural resource protection is an objective, then the construction fencing should be used in combination
with other perimeter control BMPs such as silt fence, sediment control logs or similar measures.
Design and Installation
Construction fencing may be chain link or plastic mesh and should be installed following manufacturer’s
recommendations. See Detail CF-1 for typical installations.
Do not place construction fencing in areas within work limits of machinery.
Maintenance and Removal
Inspect fences for damage; repair or replace as necessary.
Fencing should be tight and any areas with slumping or fallen posts should be reinstalled.
Fencing should be removed once construction is complete.
Construction Fence
Functions
Erosion Control No
Sediment Control No
Site/Material Management Yes
SM-3 Construction Fence (CF)
CF-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Construction Fence (CF) SM-3
November 2010 Urban Drainage and Flood Control District CF-3
Urban Storm Drainage Criteria Manual Volume 3
Vehicle Tracking Control (VTC) SM-4
November 2010 Urban Drainage and Flood Control District VTC-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph VTC-1. A vehicle tracking control pad constructed with
properly sized rock reduces off-site sediment tracking.
Description
Vehicle tracking controls provide
stabilized construction site access where
vehicles exit the site onto paved public
roads. An effective vehicle tracking
control helps remove sediment (mud or
dirt) from vehicles, reducing tracking onto
the paved surface.
Appropriate Uses
Implement a stabilized construction
entrance or vehicle tracking control where
frequent heavy vehicle traffic exits the
construction site onto a paved roadway. An
effective vehicle tracking control is
particularly important during the following conditions:
Wet weather periods when mud is easily tracked off site.
During dry weather periods where dust is a concern.
When poorly drained, clayey soils are present on site.
Although wheel washes are not required in designs of vehicle tracking controls, they may be needed at
particularly muddy sites.
Design and Installation
Construct the vehicle tracking control on a level surface. Where feasible, grade the tracking control
towards the construction site to reduce off-site runoff. Place signage, as needed, to direct construction
vehicles to the designated exit through the vehicle tracking control. There are several different types of
stabilized construction entrances including:
VTC-1. Aggregate Vehicle Tracking Control. This is a coarse-aggregate surfaced pad underlain by a
geotextile. This is the most common vehicle tracking control, and when properly maintained can be
effective at removing sediment from vehicle tires.
VTC-2. Vehicle Tracking Control with Construction Mat or Turf Reinforcement Mat. This type of
control may be appropriate for site access at very small construction sites with low traffic volume over
vegetated areas. Although this application does not typically remove sediment from vehicles, it helps
protect existing vegetation and provides a stabilized entrance.
Vehicle Tracking Control
Functions
Erosion Control Moderate
Sediment Control Yes
Site/Material Management Yes
SM-4 Vehicle Tracking Control (VTC)
VTC-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Photograph VTC-2. A vehicle tracking control pad with wheel wash
facility. Photo courtesy of Tom Gore.
VTC-3. Stabilized Construction Entrance/Exit with Wheel Wash. This is an aggregate pad, similar
to VTC-1, but includes equipment for tire washing. The wheel wash equipment may be as simple as
hand-held power washing equipment to more advance proprietary systems. When a wheel wash is
provided, it is important to direct wash water to a sediment trap prior to discharge from the site.
Vehicle tracking controls are sometimes installed in combination with a sediment trap to treat runoff.
Maintenance and Removal
Inspect the area for degradation and
replace aggregate or material used for a
stabilized entrance/exit as needed. If the
area becomes clogged and ponds water,
remove and dispose of excess sediment
or replace material with a fresh layer of
aggregate as necessary.
With aggregate vehicle tracking controls,
ensure rock and debris from this area do
not enter the public right-of-way.
Remove sediment that is tracked onto the
public right of way daily or more
frequently as needed. Excess sediment
in the roadway indicates that the
stabilized construction entrance needs
maintenance.
Ensure that drainage ditches at the
entrance/exit area remain clear.
A stabilized entrance should be removed only when there is no longer the potential for vehicle tracking to
occur. This is typically after the site has been stabilized.
When wheel wash equipment is used, be sure that the wash water is discharged to a sediment trap prior to
discharge. Also inspect channels conveying the water from the wash area to the sediment trap and
stabilize areas that may be eroding.
When a construction entrance/exit is removed, excess sediment from the aggregate should be removed
and disposed of appropriately. The entrance should be promptly stabilized with a permanent surface
following removal, typically by paving.
Vehicle Tracking Control (VTC) SM-4
November 2010 Urban Drainage and Flood Control District VTC-3
Urban Storm Drainage Criteria Manual Volume 3
SM-4 Vehicle Tracking Control (VTC)
VTC-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Vehicle Tracking Control (VTC) SM-4
November 2010 Urban Drainage and Flood Control District VTC-5
Urban Storm Drainage Criteria Manual Volume 3
SM-4 Vehicle Tracking Control (VTC)
VTC-6 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Stabilized Staging Area (SSA) SM-6
November 2010 Urban Drainage and Flood Control District SSA-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SSA-1. Example of a staging area with a gravel surface to
prevent mud tracking and reduce runoff. Photo courtesy of Douglas
County.
Description
A stabilized staging area is a clearly
designated area where construction
equipment and vehicles, stockpiles, waste
bins, and other construction-related
materials are stored. The contractor
office trailer may also be located in this
area. Depending on the size of the
construction site, more than one staging
area may be necessary.
Appropriate Uses
Most construction sites will require a
staging area, which should be clearly
designated in SWMP drawings. The layout
of the staging area may vary depending on
the type of construction activity. Staging areas located in roadways due to space constraints require
special measures to avoid materials being washed into storm inlets.
Design and Installation
Stabilized staging areas should be completed prior to other construction activities beginning on the site.
Major components of a stabilized staging area include:
Appropriate space to contain storage and provide for loading/unloading operations, as well as parking
if necessary.
A stabilized surface, either paved or covered, with 3-inch diameter aggregate or larger.
Perimeter controls such as silt fence, sediment control logs, or other measures.
Construction fencing to prevent unauthorized access to construction materials.
Provisions for Good Housekeeping practices related to materials storage and disposal, as described in
the Good Housekeeping BMP Fact Sheet.
A stabilized construction entrance/exit, as described in the Vehicle Tracking Control BMP Fact Sheet,
to accommodate traffic associated with material delivery and waste disposal vehicles.
Over-sizing the stabilized staging area may result in disturbance of existing vegetation in excess of that
required for the project. This increases costs, as well as
requirements for long-term stabilization following the
construction period. When designing the stabilized staging area,
minimize the area of disturbance to the extent practical.
Stabilized Staging Area
Functions
Erosion Control Yes
Sediment Control Moderate
Site/Material
Yes
SM-6 Stabilized Staging Area (SSA)
SSA-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
See Detail SSA-1 for a typical stabilized staging area and SSA-2 for a stabilized staging area when
materials staging in roadways is required.
Maintenance and Removal
Maintenance of stabilized staging areas includes maintaining a stable surface cover of gravel, repairing
perimeter controls, and following good housekeeping practices.
When construction is complete, debris, unused stockpiles and materials should be recycled or properly
disposed. In some cases, this will require disposal of contaminated soil from equipment leaks in an
appropriate landfill. Staging areas should then be permanently stabilized with vegetation or other surface
cover planned for the development.
Minimizing Long-Term Stabilization Requirements
Utilize off-site parking and restrict vehicle access to the site.
Use construction mats in lieu of rock when staging is provided in an area that will not be disturbed
otherwise.
Consider use of a bermed contained area for materials and equipment that do not require a
stabilized surface.
Consider phasing of staging areas to avoid disturbance in an area that will not be otherwise
disturbed.
Stabilized Staging Area (SSA) SM-6
November 2010 Urban Drainage and Flood Control District SSA-3
Urban Storm Drainage Criteria Manual Volume 3
SM-6 Stabilized Staging Area (SSA)
SSA-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Street Sweeping and Vacuuming (SS) SM-7
November 2010 Urban Drainage and Flood Control District SS-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SS-1. A street sweeper removes sediment and potential
pollutants along the curb line at a construction site. Photo courtesy of
Tom Gore.
Description
Street sweeping and vacuuming remove
sediment that has been tracked onto
roadways to reduce sediment transport
into storm drain systems or a surface
waterway.
Appropriate Uses
Use this practice at construction sites
where vehicles may track sediment
offsite onto paved roadways.
Design and Installation
Street sweeping or vacuuming should be
conducted when there is noticeable
sediment accumulation on roadways adjacent to the construction site. Typically, this will be concentrated
at the entrance/exit to the construction site. Well-maintained stabilized construction entrances, vehicle
tracking controls and tire wash facilities can help reduce the necessary frequency of street sweeping and
vacuuming.
On smaller construction sites, street sweeping can be conducted manually using a shovel and broom.
Never wash accumulated sediment on roadways into storm drains.
Maintenance and Removal
Inspect paved roads around the perimeter of the construction site on a daily basis and more
frequently, as needed. Remove accumulated sediment, as needed.
Following street sweeping, check inlet protection that may have been displaced during street
sweeping.
Inspect area to be swept for materials that may be hazardous prior to beginning sweeping operations.
Street Sweeping/ Vacuuming
Functions
Erosion Control No
Sediment Control Yes
Site/Material Management Yes
30
Appendix E
Web Soil Survey
Soil Map—Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 1 of 3
4495480 4495550 4495620 4495690 4495760 4495830 4495900
4495480 4495550 4495620 4495690 4495760 4495830 4495900
496970 497040 497110 497180 497250 497320 497390 497460 497530 497600 497670
496970 497040 497110 497180 497250 497320 497390 497460 497530 497600 497670
40° 36' 50'' N
105° 2' 9'' W
40° 36' 50'' N
105° 1' 38'' W
40° 36' 35'' N
105° 2' 9'' W
40° 36' 35'' N
105° 1' 38'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 150 300 600 900
Feet
0 45 90 180 270
Meters
Map Scale: 1:3,300 if printed on A landscape (11" x 8.5") sheet.
Soil Map may not be valid at this scale.
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Map Unit Polygons
Soil Map Unit Lines
Soil Map Unit Points
Special Point Features
Blowout
Borrow Pit
Clay Spot
Closed Depression
Gravel Pit
Gravelly Spot
Landfill
Lava Flow
Marsh or swamp
Mine or Quarry
Miscellaneous Water
Perennial Water
Rock Outcrop
Saline Spot
Sandy Spot
Severely Eroded Spot
Sinkhole
Slide or Slip
Sodic Spot
Spoil Area
Stony Spot
Very Stony Spot
Wet Spot
Other
Special Line Features
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
Map Unit Legend
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
54 Kim loam, 3 to 5 percent
slopes
0.0 0.1%
94 Satanta loam, 0 to 1 percent
slopes
3.0 7.9%
101 Stoneham loam, 1 to 3 percent
slopes
28.4 75.4%
102 Stoneham loam, 3 to 5 percent
slopes
6.3 16.6%
Totals for Area of Interest 37.6 100.0%
Soil Map—Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 3 of 3
Larimer County Area, Colorado
54—Kim loam, 3 to 5 percent slopes
Map Unit Setting
National map unit symbol: jpwy
Elevation: 4,800 to 5,600 feet
Mean annual precipitation: 13 to 15 inches
Mean annual air temperature: 48 to 50 degrees F
Frost-free period: 135 to 150 days
Farmland classification: Farmland of statewide importance
Map Unit Composition
Kim and similar soils: 90 percent
Minor components: 10 percent
Estimates are based on observations, descriptions, and transects of
the mapunit.
Description of Kim
Setting
Landform: Fans
Landform position (three-dimensional): Base slope
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Mixed alluvium
Typical profile
H1 - 0 to 7 inches: loam
H2 - 7 to 60 inches: loam, clay loam, sandy clay loam
H2 - 7 to 60 inches:
H2 - 7 to 60 inches:
Properties and qualities
Slope: 3 to 5 percent
Depth to restrictive feature: More than 80 inches
Drainage class: Well drained
Runoff class: Low
Capacity of the most limiting layer to transmit water
(Ksat): Moderately high to high (0.60 to 2.00 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum content: 15 percent
Maximum salinity: Nonsaline to slightly saline (0.0 to 4.0
mmhos/cm)
Available water supply, 0 to 60 inches: Very high (about 26.5
inches)
Interpretive groups
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 4e
Map Unit Description: Kim loam, 3 to 5 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 1 of 2
Hydrologic Soil Group: B
Ecological site: R067XY002CO - Loamy Plains
Hydric soil rating: No
Minor Components
Thedalund
Percent of map unit: 4 percent
Hydric soil rating: No
Stoneham
Percent of map unit: 3 percent
Hydric soil rating: No
Fort collins
Percent of map unit: 2 percent
Hydric soil rating: No
Aquic haplustolls
Percent of map unit: 1 percent
Landform: Swales
Hydric soil rating: Yes
Data Source Information
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 15, Jun 9, 2020
Map Unit Description: Kim loam, 3 to 5 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 2 of 2
Larimer County Area, Colorado
94—Satanta loam, 0 to 1 percent slopes
Map Unit Setting
National map unit symbol: 2wz89
Elevation: 3,670 to 5,410 feet
Mean annual precipitation: 10 to 23 inches
Mean annual air temperature: 45 to 52 degrees F
Frost-free period: 105 to 160 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Satanta and similar soils: 90 percent
Minor components: 10 percent
Estimates are based on observations, descriptions, and transects of
the mapunit.
Description of Satanta
Setting
Landform: Alluvial fans
Landform position (two-dimensional): Backslope
Landform position (three-dimensional): Head slope
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Alluvium
Typical profile
Ap - 0 to 10 inches: loam
Bt - 10 to 17 inches: clay loam
C - 17 to 79 inches: loam
Properties and qualities
Slope: 0 to 1 percent
Depth to restrictive feature: More than 80 inches
Drainage class: Well drained
Runoff class: Negligible
Capacity of the most limiting layer to transmit water
(Ksat): Moderately high (0.20 to 0.60 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum content: 10 percent
Maximum salinity: Nonsaline to very slightly saline (0.0 to 2.0
mmhos/cm)
Available water supply, 0 to 60 inches: Very high (about 12.3
inches)
Interpretive groups
Land capability classification (irrigated): 1
Land capability classification (nonirrigated): 2e
Map Unit Description: Satanta loam, 0 to 1 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 1 of 2
Hydrologic Soil Group: C
Ecological site: R072XY111KS - Sandy Plains
Hydric soil rating: No
Minor Components
Nunn
Percent of map unit: 5 percent
Landform: Terraces
Landform position (three-dimensional): Tread
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: R072XY108KS - Loamy Lowland
Hydric soil rating: No
Fort collins
Percent of map unit: 5 percent
Landform: Alluvial fans
Landform position (two-dimensional): Backslope
Landform position (three-dimensional): Head slope
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: R072XY111KS - Sandy Plains
Hydric soil rating: No
Data Source Information
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 15, Jun 9, 2020
Map Unit Description: Satanta loam, 0 to 1 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 2 of 2
Larimer County Area, Colorado
101—Stoneham loam, 1 to 3 percent slopes
Map Unit Setting
National map unit symbol: jptt
Elevation: 4,800 to 5,600 feet
Mean annual precipitation: 13 to 15 inches
Mean annual air temperature: 48 to 50 degrees F
Frost-free period: 135 to 150 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Stoneham and similar soils: 90 percent
Minor components: 10 percent
Estimates are based on observations, descriptions, and transects of
the mapunit.
Description of Stoneham
Setting
Landform: Terraces, benches
Landform position (three-dimensional): Base slope, tread
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Mixed alluvium and/or eolian deposits
Typical profile
H1 - 0 to 4 inches: loam
H2 - 4 to 10 inches: clay loam, sandy clay loam, loam
H2 - 4 to 10 inches: loam, clay loam, sandy clay loam
H2 - 4 to 10 inches:
H3 - 10 to 60 inches:
H3 - 10 to 60 inches:
H3 - 10 to 60 inches:
Properties and qualities
Slope: 1 to 3 percent
Depth to restrictive feature: More than 80 inches
Drainage class: Well drained
Runoff class: Low
Capacity of the most limiting layer to transmit water
(Ksat): Moderately high to high (0.60 to 2.00 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum content: 15 percent
Maximum salinity: Nonsaline to very slightly saline (0.0 to 2.0
mmhos/cm)
Available water supply, 0 to 60 inches: Very high (about 27.5
inches)
Map Unit Description: Stoneham loam, 1 to 3 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 1 of 2
Interpretive groups
Land capability classification (irrigated): 2e
Land capability classification (nonirrigated): 3e
Hydrologic Soil Group: B
Ecological site: R067XY002CO - Loamy Plains
Hydric soil rating: No
Minor Components
Fort collins
Percent of map unit: 5 percent
Hydric soil rating: No
Kim
Percent of map unit: 5 percent
Hydric soil rating: No
Data Source Information
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 15, Jun 9, 2020
Map Unit Description: Stoneham loam, 1 to 3 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 2 of 2
Larimer County Area, Colorado
102—Stoneham loam, 3 to 5 percent slopes
Map Unit Setting
National map unit symbol: 2x0j1
Elevation: 3,500 to 6,500 feet
Mean annual precipitation: 12 to 18 inches
Mean annual air temperature: 46 to 54 degrees F
Frost-free period: 115 to 155 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Stoneham and similar soils: 85 percent
Minor components: 15 percent
Estimates are based on observations, descriptions, and transects of
the mapunit.
Description of Stoneham
Setting
Landform: Low hills, interfluves
Landform position (two-dimensional): Summit
Landform position (three-dimensional): Interfluve
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Mixed alluvial and/or eolian tertiary aged
pedisediment
Typical profile
Ap - 0 to 4 inches: loam
Bt - 4 to 9 inches: clay loam
Btk - 9 to 13 inches: clay loam
Bk1 - 13 to 18 inches: loam
Bk2 - 18 to 34 inches: loam
C - 34 to 80 inches: loam
Properties and qualities
Slope: 3 to 5 percent
Depth to restrictive feature: More than 80 inches
Drainage class: Well drained
Runoff class: Low
Capacity of the most limiting layer to transmit water
(Ksat): Moderately high to high (0.20 to 2.00 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum content: 12 percent
Maximum salinity: Nonsaline to very slightly saline (0.1 to 2.0
mmhos/cm)
Sodium adsorption ratio, maximum: 0.5
Available water supply, 0 to 60 inches: High (about 9.1 inches)
Map Unit Description: Stoneham loam, 3 to 5 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 1 of 2
Interpretive groups
Land capability classification (irrigated): 4e
Land capability classification (nonirrigated): 4c
Hydrologic Soil Group: C
Ecological site: R067BY002CO - Loamy Plains
Hydric soil rating: No
Minor Components
Satanta
Percent of map unit: 5 percent
Landform: Interfluves
Landform position (two-dimensional): Summit
Landform position (three-dimensional): Interfluve
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: R067BY002CO - Loamy Plains
Hydric soil rating: No
Kimst
Percent of map unit: 5 percent
Landform: Interfluves, low hills
Landform position (two-dimensional): Shoulder, backslope
Landform position (three-dimensional): Side slope
Down-slope shape: Convex
Across-slope shape: Convex
Ecological site: R067BY002CO - Loamy Plains
Hydric soil rating: No
Weld
Percent of map unit: 5 percent
Landform: Interfluves
Landform position (two-dimensional): Summit
Landform position (three-dimensional): Interfluve
Down-slope shape: Linear
Across-slope shape: Linear
Ecological site: R067BY002CO - Loamy Plains
Hydric soil rating: No
Data Source Information
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 15, Jun 9, 2020
Map Unit Description: Stoneham loam, 3 to 5 percent slopes---Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 2 of 2
31
Appendix F
Calculations
PROJECT INFORMATION
PROJECT NAME:
PROJECT #:
POND NAME:
DATE:
Required Sediment Basin Storage Volume:
Sedimentation Sizing Method: COA Temporary Sediment Basin
(>15 Acre Tributary Area)
Volume Requirements:
>15 Acres
>15 Acres
*COA SB Detail, Pg. 3
**UDFCD (V.3), Chapter 7, Page SB-1
Disturbed TributaryArea = 88.17 (acres)
Undisturbed Tributary Area= 14.75 (acres)
100% Storage= 245,434 (cubic feet)
100% Storage Above First Orifice= 5.63 (ac-ft)
1.88 (ac-ft)
MONTAVA PHASE G
1/3 Storage Below First Orifice =
19.1354
SEDIMENT POND E
11/14/2022
*2,700 cubic feet/acre of tributary area (Disturbed),
**500 cubic feet/acres of tributary area (Undisturbed)
11/14/2022 5:23 PM
POND E
G:\LOVATO\19.1354-Montava Phase 1a\ENG\EROSION\sed basin riser pipe\Pond E - Sediment Volume.xls
PROJECT INFORMATION
PROJECT NAME:
PROJECT #:
POND NAME:
DATE:
Sediment Basin Volume
1/3 Sedimentation 1.88 (ac-ft)
100% Storage Above 1st Orifice 5.63 (ac-ft)
D= 1/3 Volume
For Sedimentation 1.88 (ac-ft)
Sedimentation Surface Elevation 4997.79
For Total Storage 7.51 (ac-ft)
Sedimentation Surface Elevation 5000.22
Incremental Volume=
Contour Elevation
Contour Area
(ft²)
Cumulative Volume
(ft³)
Cumulative Volume
(acre-ft)
4994.00 20.7 0 0.00
4995.00 4913.4 1751 0.04
4996.00 17893.2 12479 0.29
4997.00 39034.8 40264 0.92
4998.00 66894.2 92607 2.13
4999.00 98488.4 174791 4.01
5000.00 136275.6 291663 6.70
5001.00 180638.1 449599 10.32
5002.00 231574.2 655179 15.04
5003.00 288912.7 914894 21.00
5004.00 347975.7 1232881 28.30
5004.44 371893.5 1391223 31.94
MONTAVA PHASE G
19.1354
SEDIMENT POND E
11/14/2022
27785
52343
82184
116872
157937
205580
158342
Volume
(ft³)
0
1751
10728
259715
317987
11/14/2022 5:23 PM
POND E
G:\LOVATO\19.1354-Montava Phase 1a\ENG\EROSION\sed basin riser pipe\Pond E - Sed Basin_WSEL.xlsm
PROJECT INFORMATION
PROJECT NAME:
PROJECT #:
POND NAME:
DATE:
5.63 AC-FT Above First Orifice
1.88 AC-FT Below First Orifice
5000.22 FT
4997.79 FT
(AT 33% REQ'D STORAGE VOL OR 2.5FT MIN.)
2.43 FT
5.63 AC-FT
40 HRS
2.43 FT
0.0001 FT/FT
Ao
= 19.97 IN
2
/ROW
1
8
USE: 2"x10.0" RECTANGLUAR HOLE, 4" ON CENTER
NUMBER OF COLUMNS =
NUMBER OF ROWS =
(EQUATION EDB-3,
UD&FCD VOLUME III)
TD
S
0.09
H
(2.6S^0.3)
V (DESIGN VOLUME) =
TD
(DRAIN TIME) =
H (DEPTH OF VOLUME) =
S (SLOPE) =
33% REQUIRED SEDIMENTATION VOLUME=
SEDIMENTATION WSEL =
ELEV. @ 1
ST
PERFORATION =
DEPTH @ 1ST PERF. =
AREA REQ'D PER ROW, Ao
= 88V
(0.95/H^0.085)
MONTAVA PHASE G
19.1354
SEDIMENT POND E
11/14/2022
TEMPORARY SEDIMENT BASIN RISER PIPE
100% REQUIRED SEDIMENTATION VOLUME=
11/14/2022 5:24 PM
POND E
G:\LOVATO\19.1354-Montava Phase 1a\ENG\EROSION\sed basin riser pipe\Pond E - Sediment Basin_Riser Pipe.xls
32
Appendix G
Erosion Control Plans
EROSION CONTROL COVER SHEET
C2.0
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
STORMWATER MANAGEMENT PLANS FOR
MONTAVA - PHASE G
A PARCEL OF LAND SITUATED IN THE SOUTH HALF OF SECTION 32,
TOWNSHIP 8 NORTH, RANGE 68 WEST OF THE SIXTH PRINCIPAL MERIDIAN,
CITY OF FORT COLLINS, COUNTY OF LARIMER,
STATE OF COLORADO
811
VICINITY MAP
SITE
”
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
EROSION CONTROL NOTES
“ ”
“ ”
“
”
C2.1
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INITIAL EROSION CONTROL PLAN
C2.2
SEE SHEET
C2.3
SEE SHEET C2.4
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INITIAL EROSION CONTROL PLAN
C2.3
SEE SHEET C2.2
SEE SHEET
C2.5
SEE SHEET
C2.4
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INITIAL EROSION CONTROL PLAN
C2.4
SEE SHEET
C2.2
SEE SHEET
C2.5
SEE SHEET C2.5
SEE SHEET
C2.3
SEE SHEET
C2.7
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INITIAL EROSION CONTROL PLAN
C2.5
SEE SHEET
C2.3
SEE SHEET
C2.4
SEE SHEET
C2.4
SEE SHEET C2.6
SEE SHEET C2.7
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INITIAL EROSION CONTROL PLAN
C2.6
SEE SHEET C2.5
SEE SHEET C2.7
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INITIAL EROSION CONTROL PLAN
C2.7
SEE SHEET C2.4
SEE SHEET C2.5 SEE SHEET C2.6
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INTERIM EROSION CONTROL PLAN
C2.8
SEE SHEET
C2.9
SEE SHEET C2.10
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INTERIM EROSION CONTROL PLAN
C2.9
SEE SHEET C2.8
SEE SHEET
C2.11
SEE SHEET C2.10
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INTERIM EROSION CONTROL PLAN
C2.10
SEE SHEET C2.8
SEE SHEET
C2.11
SEE SHEET C2.11
SEE SHEET C2.9
SEE SHEET
C2.13
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INTERIM EROSION CONTROL PLAN
C2.11
SEE SHEET
C2.9
SEE SHEET
C2.10
SEE SHEET
C2.10
SEE SHEET C2.12
SEE SHEET C2.13
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INTERIM EROSION CONTROL PLAN
C2.12
SEE SHEET C2.11
SEE SHEET C2.13
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
INTERIM EROSION CONTROL PLAN
C2.13
SEE SHEET C2.10
SEE SHEET C2.11 SEE SHEET C2.12
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
FINAL EROSION CONTROL PLAN
C2.14
SEE SHEET
C2.15
SEE SHEET C2.16
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
FINAL EROSION CONTROL PLAN
C2.15
SEE SHEET C2.14
SEE SHEET
C2.17
SEE SHEET C2.16
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
FINAL EROSION CONTROL PLAN
C2.16
SEE SHEET C2.14
SEE SHEET
C2.17
SEE SHEET C2.17
SEE SHEET
C2.15
SEE SHEET
C2.19
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
FINAL EROSION CONTROL PLAN
C2.17
SEE SHEET
C2.15
SEE SHEET
C2.16
SEE SHEET
C2.16
SEE SHEET C2.18
SEE SHEET
C2.19
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
FINAL EROSION CONTROL PLAN
C2.18
SEE SHEET C2.17
SEE SHEET C2.19
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
FINAL EROSION CONTROL PLAN
C2.19
SEE SHEET C2.16
SEE SHEET C2.17 SEE SHEET C2.18
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN
- INITIAL & INTERIM
C2.20
SEE SHEET C2.21
SEE SHEET C2.22
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN
- INITIAL & INTERIM
C2.21
SEE SHEET C2.23
SEE SHEET C2.20
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN
- INITIAL & INTERIM
C2.22
SEE SHEET C2.20
SEE SHEET C2.23
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN
- INITIAL & INTERIM
C2.23
SEE SHEET C2.21
SEE SHEET C2.22
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN - FINAL
C2.24
SEE SHEET C2.25
SEE SHEET C2.26
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN - FINAL
C2.25
SEE SHEET C2.27
SEE SHEET C2.24
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN - FINAL
C2.26
SEE SHEET C2.24
SEE SHEET C2.27
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
OFFSITE EROSION CONTROL PLAN - FINAL
C2.27
SEE SHEET C2.25
SEE SHEET C2.26
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
EROSION CONTROL DETAILS
C2.28
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
EROSION CONTROL DETAILS
C2.29
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
EROSION CONTROL DETAILS
C2.30
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
UTILITY PLANS
EROSION CONTROL DETAILS
C2.31
SEDIMENT BASIN INFORMATION
SEDIMENT BASIN DISTURBED TRIBUTARY AREA
(ACRES)
UNDISTURBED TRIBUTARY AREA
(ACRES) REQUIRED STORAGE (ACRE-FT) PROVIDED STORAGE (ACRE-FT)
E
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
STORMWATER MANAGEMENT PLANS FOR
MONTAVA - PHASE G
ROADWAY & INFRASTRUCTURE PLANS
A PARCEL OF LAND SITUATED IN THE SOUTH HALF OF SECTION 32,
TOWNSHIP 8 NORTH, RANGE 68 WEST OF THE SIXTH PRINCIPAL MERIDIAN,
CITY OF FORT COLLINS, COUNTY OF LARIMER,
STATE OF COLORADO
811
VICINITY MAP
SITE
#
EROSION CONTROL COVER SHEET
R2.0
”
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
“ ”
“ ”
“
”
EROSION CONTROL NOTES
R2.1
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.2
INITIAL EROSION CONTROL PLAN -
MOUNTAIN VISTA DR.
811
SEE BELOW LEFT SEE BELOW LEFT
SEE ABOVE RIGHT SEE ABOVE RIGHT
SEE SHEET R2.3
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.3
INITIAL EROSION CONTROL PLAN - N.
TIMBERLINE RD.
811
SEE BELOW LEFT
SEE ABOVE RIGHT SEE ABOVE RIGHT
SEE BELOW LEFT
SEE ABOVE RIGHT
SEE SHEET R2.2
SEE SHEET R2.2
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.4
INITIAL EROSION CONTROL PLAN - N.
TIMBERLINE RD.
811
SEE SHEET R2.3
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.5
INTERIM EROSION CONTROL PLAN -
MOUNTAIN VISTA DR.
811
SEE BELOW LEFT SEE BELOW LEFT
SEE ABOVE RIGHT SEE ABOVE RIGHT
SEE SHEET R2.6
SEE SHEET R2.6
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.6
INTERIM EROSION CONTROL PLAN -
N. TIMBERLINE RD.
811
SEE BELOW LEFT
SEE ABOVE RIGHT SEE ABOVE RIGHT
SEE SHEET R2.5
SEE BELOW LEFT
SEE SHEET R2.5
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.7
INTERIM EROSION CONTROL PLAN -
N. TIMBERLINE RD.
811
SEE SHEET R2.6
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.8
FINAL EROSION CONTROL PLAN -
MOUNTAIN VISTA DR.
811
SEE BELOW LEFT SEE BELOW LEFT
SEE ABOVE RIGHT
SEE ABOVE RIGHT
SEE SHEET R2.9
SEE SHEET R2.9
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.9
FINAL EROSION CONTROL PLAN - N.
TIMBERLINE RD.
811
SEE BELOW LEFT
SEE ABOVE RIGHT SEE ABOVE RIGHT
SEE SHEET __
SEE BELOW LEFT
SEE ABOVE RIGHT
SEE SHEET R2.8
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
R2.10
FINAL EROSION CONTROL PLAN - N.
TIMBERLINE RD.
811
SEE SHEET R2.9
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
EROSION CONTROL DETAILS
R2.11
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
EROSION CONTROL DETAILS
R2.12
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
EROSION CONTROL DETAILS
R2.13
MARTIN/MARTIN
C O N S U L T I N G E N G I N E E R S
12499 WEST COLFAX AVENUE, LAKEWOOD, COLORADO 80215
303.431.6100 MARTINMARTIN.COM
NOT FOR CONSTRUCTION
MONTAVA SUBDIVISION
PHASE G
ROADWAY &
INFRASTRUCTURE PLANS
EROSION CONTROL DETAILS
R2.14
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 15, Jun 9, 2020
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Jul 19, 2018—Aug
10, 2018
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Soil Map—Larimer County Area, Colorado
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
9/28/2021
Page 2 of 3
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