HomeMy WebLinkAboutMAX FLATS - PDP/FDP - FDP130008 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT (3)April 24, 2013
EROSION CONTROL REPORT
MAX Flats
Fort Collins, Colorado
Prepared for:
Brinkman Development, LLC
3003 East Harmony Road, Suite 300
Fort Collins, CO 80528
Prepared by:
200 South College Avenue, Suite 10
Fort Collins, Colorado 80524
Phone: 970.221.4158 Fax: 970.221.4159
www.northernengineering.com
Project Number: 860-001
3 This Report is consciously provided as a PDF.
Please consider the environment before printing this document in its entirety.
When a hard copy is absolutely necessary, we recommend double-sided printing.
April 24, 2013
City of Fort Collins
Stormwater Utility
700 Wood Street
Fort Collins, CO 80521
RE: Erosion Control Report for MAX Flats
Dear Staff,
Northern Engineering Services, Inc. is pleased to submit this Erosion Control Report (ECR) for MAX Flats. The
objectives of this Erosion Control Report (ECR) are to identify potential sources of pollution resulting from the
construction activity associated with the site improvements described herein and recommend Best
Management Practices (BMPs) that can be used to reduce or eliminate the likelihood of these pollutants
entering stormwater discharges from the site.
If you should have any questions or comments as you review this report, please feel free to contact us at your
convenience.
Sincerely,
NORTHERN ENGINEERING SERVICES, INC.
Herman Feissner, P.E.
Project Engineer
MAX Flats
Stormwater Management Plan
TABLE OF CONTENTS
Vicinity Map
1.0 General Requirements..............................................................................................1
1.1 Objectives...............................................................................................................1
1.2 Definitions ..............................................................................................................1
2.0 Narrative Site Description .........................................................................................2
2.1 Existing Site Description ............................................................................................2
2.2 Wind and Rainfall Erodibility .....................................................................................2
2.3 Nature of Construction Activity ...................................................................................2
2.4 Sequence of Major Activities ......................................................................................2
2.5 Site Disturbance ......................................................................................................2
2.6 Existing Data...........................................................................................................3
2.7 Existing Vegetation ...................................................................................................3
2.8 Potential Pollution Sources ........................................................................................3
2.9 Receiving Waters .....................................................................................................3
Figure 1 – Existing Drainage Infrastructure ........................................................................................4
3.0 Stormwater Management Controls .............................................................................5
3.1 Best Management Practices (BMPs) for Stormwater Pollution Prevention ..........................5
3.2 Structural Practices for Erosion and Sediment Control ....................................................5
3.3 Non-Structural Practices for Erosion and Sediment Control .............................................7
3.4 Phased BMP Installation ...........................................................................................8
3.5 Material Handling and Spill Prevention ........................................................................8
3.6 Waste Management and Disposal ...............................................................................9
4.0 Final Stabilization and Long-Term Stormwater Management ....................................... 10
4.1 Final Stabilization .................................................................................................. 10
4.2 Long-Term Stormwater Management ......................................................................... 10
5.0 Inspection and Maintenance ................................................................................... 11
5.1 BMP Inspection ..................................................................................................... 10
5.2 BMP Maintenance ................................................................................................. 10
References 12
MAX Flats
Stormwater Management Plan
LIST OF TABLES:
Table 1 – Construction Schedule ........................................................................................... 8
Table 2 – Native Grass Seed Mix ......................................................................................... 10
APPENDICES:
APPENDIX A – Erosion Control Plan | Static and Dynamic Site Plans
APPENDIX B – Erosion Control Details
APPENDIX C – Landscape Plan
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Erosion Control Report 1
1.0 General Requirements
1.1 Objectives
The objectives of this Erosion Control Report (ECR) are to identify potential sources of pollution
resulting from construction activity associated with the site improvements described herein and
recommend Best Management Practices (BMPs) that can be used to reduce the pollutants in
stormwater discharges from the site. The ECR must be completed and implemented at the time the
project breaks ground and revised as necessary while construction proceeds to accurately reflect the
conditions and practices at the site.
1.2 Definitions
Best Management Practices (BMPs) – BMPs encompass a wide range of erosion and sediment
control practices, both structural and non-structural in nature, which are intended to reduce or
eliminate potential water quality impacts from construction site stormwater runoff.
Erosion Control BMPs – These practices are intended to prevent the erosion of soil. A few common
examples include: minimizing the amount of disturbed area through phasing, temporary
stabilization and preserving existing vegetation.
Sediment Control BMPs – These practices are designed to remove sediment from runoff. Examples
of few include: straw wattles, silt fence and inlet protection.
Non-structural BMPs – These BMPs prevent or limit the entry of pollutants into stormwater at their
source through operational or managerial techniques. Some examples include: the preservation of
natural vegetation, preventive maintenance and spill response procedures.
Structural BMPs – Structural practices are designed to control on-site erosion and prevent sediment
from migrating within the project site as well as off-site during construction. This type of BMP
includes physical processes ranging from diversion structures to inlet protection and silt fence.
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Erosion Control Report 2
2.0 Narrative Site Description
2.1 Existing Site Description
The project site is located in the Northeast Quarter of Section 14, Township 7 North, Range 69
West of the 6th Principal Meridian, City of Fort Collins, County of Larimer, State of Colorado. More
specifically, the project is located at 203 West Mulberry Street. The project site is bordered to the
north by Mulberry Street (100' Right-of-Way); to the south by existing single-family homes; to the
east by Mason Street (100' Right-of-Way); and to the west by multi-family housing, an alley (20'
Right-of-Way) and a single-family lot.
The existing site improvements include a two-level concrete block building with a footprint of
approximately 3050 square-feet. The remainder of the site is almost entirely paved. The existing
landscaping is minimal and generally limited to narrow strips of shrubs along the north and east
edges of the property.
2.2 Wind and Rainfall Erodibility
The site is located within a moderate risk Erodibility Zone per the City of Fort Collins Wind
Erodibility Map. According to the Natural Resources Conservation Service website -
www.websoilsurvey.nrcs.usda.gov, the applicable soil erosion factor (K), which indicates the
susceptibility of a soil to sheet and rill erosion, is 0.28. This value is indicative of soils moderately
susceptible to rainfall erosion.
Impervious area (i.e., roof area, concrete walks and concrete parking area) and landscaping will
permanently stabilize the areas disturbed by the proposed construction activity; therefore, the
likelihood of erosion and sediment problems occurring on-site is minimal. Most of the proposed
landscaped area is situated around along the project property lines. During the interim period, in
which the disturbed areas are open, the BMPs described herein were selected to prevent erosion
and limit sediment migration.
2.3 Nature of Construction Activity
The proposed redevelopment will completely remove the above-grade structure and adjacent
hardscape. The project will consist of a concrete parking area and four stories of residential units
over a ground level containing commercial/retail flex space and parking.
2.4 Sequence of Major Activities
To complete the project, many basic construction activities will take place. The project will begin by
removing the existing site improvements (i.e., structure and asphalt paving). The installation,
removal/replacement, or re-routing of existing utilities (e.g., electric, gas, sanitary sewer, domestic
water and storm drain) will occur next. While building foundations are being constructed, concrete
barrier curbs will be installed around the parking area. The concrete paving in the parking area will
likely follow completion of exterior construction. The fine grading of the landscaped areas and the
installation of landscaping will mark the completion of the construction activities.
2.5 Site Disturbance
The project site is approximately 0.70 acre in size. The area that will be disturbed by construction
activity is approximately 0.70 acre.
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2.6 Existing Data
In order to complete the associated construction plans, a topographical survey of the site was
completed. The survey consisted of field measurements made by Northern Engineering Services,
Inc. in July 2011.
The site-specific subsurface exploration was performed by Earth Engineering Consultants, Inc.
Detailed results from this work are contained in the Geotechnical Subsurface Exploration Report
Proposed 5-Story Mixed Use Building 203 West Mulberry Street Fort Collins, Colorado (EEC
Project No. 1122094) dated December 3, 2012.
2.7 Existing Vegetation
The pre-disturbance individual plant density within the existing landscaped areas is greater than 75
percent. The existing vegetative cover is consistent with the age and upkeep of project site. Final
stabilization with an individual plant density of at least 70 percent of pre-disturbance levels, or
equivalent permanent, physical erosion reduction methods will be achieved. The total disturbed
area will be permanently stabilized with concrete, roof area and landscaping such as sod and
planting beds. It is highly recommended that pre-construction photos be taken to clearly document
vegetative conditions prior any disturbance activities.
2.8 Potential Pollution Sources
As is typical with most construction sites, there are a number of potential pollution sources which
could affect water quality. It is not possible for this report to identify all the materials that will be
used or stored on the construction site. It is the sole responsibility of the contractor to identify and
properly handle materials that are potential pollution sources. The following are some common
examples of potential pollution sources:
x Exposed and stored soils
x Vehicle tracking of sediments
x Management of contaminated soils
x Outdoor storage of building materials, fertilizers, chemicals, etc.
x Vehicle and equipment maintenance and fueling
x Significant dust or particulate generating processes
x Routine maintenance activities involving fertilizers, pesticides, detergents, fuels,
solvents, oils, etc.
x On-site waste disposal practices (waste piles, dumpsters, etc.)
x Concrete truck/equipment washing, including the concrete truck chute and
associated fixtures and equipment
x Dedicated asphalt and concrete batch plants
x Non-industrial waste sources such as worker trash and portable toilets
x Other areas or procedures where potential spills can occur
Management of Contaminated Soils: We are not aware of on-site contaminated soils. However, the
contractor should conduct a thorough, pre-construction environmental site assessment. If
contaminated soils are discovered, the contractor will identify appropriate practices and procedures
for the specific contaminants discovered on-site.
Loading and Unloading Operations: During site demolition, material loading and unloading will
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Erosion Control Report 4
occur on-site. As site development and building construction progresses, space constraints will limit
the number of on-site locations for loading and unloading activities to the on-site parking area. The
contractor will be responsible for the proper handling and management of pollution sources during
loading and unloading operations.
Dedicated Asphalt and Concrete Batch Plants: Neither a dedicated asphalt or concrete batch plant
will be constructed on-site.
2.9 Receiving Waters
The site currently surface drains from southwest to northeast along flat grades of less than one
percent. Two existing off-site curb inlets are located at the southwest corner of Mulberry and Mason
Streets, along the south and west flowlines of each, respectively. These inlets collect existing
developed site runoff and discharge it to the public storm sewer system in Mulberry Street (see
Figure 1). This system outfalls to the Udall Natural Area, where stormwater quality is provided,
prior to draining into the Poudre River.
Figure 1 – Existing Drainage Infrastructure
Project
Site
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Erosion Control Report 5
3.0 Stormwater Management Controls
3.1 Best Management Practices (BMPs) for Stormwater Pollution Prevention
Best Management Practices (BMPs) are loosely defined as a method, activity, maintenance
procedure or other management practice for reducing the amount of pollution entering a water
body. The term originated from rules and regulations in Section 208 of the Clean Water Act (CWA).
Starting with mobilization, and throughout the entire construction of the buildings, erosion control
devices should be installed and maintained to minimize pollutant migration. The BMPs may be
installed or implemented in phases, or not at all, depending on actual conditions encountered at the
site. It is the responsibility of the contractor to make the determination as to what practices should
be employed and when. In the event that a review agency deems BMPs to be insufficient, it shall be
the responsibility of the contractor to implement modifications as directed.
Table 1 (see below) depicts the construction sequence and associated BMPs. The Erosion Control
Static Site Plan (Refer to sheet C601 in Appendix A) illustrates an assumed location for each BMP.
Details for recommended BMPs are included in Appendix B. These details should be used for
additional information on installation and maintenance of BMPs described herein.
3.2 Structural Practices for Erosion and Sediment Control
Structural BMPs are physical devices that prevent or minimize water quality impacts associated
with construction site stormwater runoff. These devices can be temporary or permanent, and the
installation of individual components will vary depending on the stage of construction.
Again, the final determination for which BMPs will be installed, where they will be located and
when they will be installed shall be made by the contractor.
Silt Fencing (Phases I - IV)
Silt fencing shall be provided to prevent migration of sediment off-site into the public right-
of-way and onto neighboring properties. All silt fencing shall be installed prior to any land
disturbing activity (e.g., stockpiling, stripping, grading, excavation, earthwork activities and
etc.).
Silt fence inspections should identify tears or holes in the material as well as check for
slumping fence or undercut areas that allow flows to bypass the fencing. Any damaged
sections of fencing should be repaired or replaced. Sediment accumulations equal to or
greater than six inches behind the silt fence should be removed to maintain BMP
effectiveness.
At a minimum, it is suggested that silt fencing shall be located along the south and east
property lines of the project site to prevent sediment from leaving the site and entering
neighboring properties.
Vehicle Tracking Control Pads (Phases I -II)
A vehicle tracking control pad shall be provided to minimize tracking of mud and sediment
onto paved surfaces and neighboring roadways. The vehicle tracking control pad shall be
installed prior to any earth disturbing activity (e.g., stockpiling, stripping, grading, etc.). A
vehicle tracking control pad should be located at all existing and future vehicle accesses
being used during any of the construction phases. These locations will primarily be dictated
by gates or openings in the temporary construction fencing.
The vehicle tracking pads should be inspected for degradation. The aggregate material
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Erosion Control Report 6
should remain rough and be replaced if the area becomes clogged with water and/or excess
sediment.
Inlet Protection (Phases I - IV)
Three different types of inlet protection are recommended for preventing sediment from
entering the proposed on-site inlets and existing off-site inlets. The first is a TenCate Mirafi
Dandy Sack (or approved equal) Area Inlet Filter (IF). This BMP should be installed the
proposed area inlet within the new concrete parking area. The second inlet protection
method, which relies on straw wattles (see detail 02 on sheet C602), should be used to
protect the proposed landscape area drain. The third inlet protection BMP is curb inlet
protection (see detail 03 on sheet C602). It should be placed at each of the existing
combination inlets in Mason and Mulberry Streets.
Installing these BMPs before construction begins should prevent sediment from entering the
proposed storm drain system as well as the existing storm drain system. The area inlet
protection should be inspected regularly and maintained as necessary. It will be left to the
discretion of the contractor as to when maintenance or replacement is necessary. The
contractor is encouraged to follow the manufacturer recommendations.
Sediment Control Log – aka “Straw Wattles” (Phases I - IV)
A Sediment Control Log is a linear roll made of natural materials, such as straw, coconut
fiber or other fibrous material trenched into the ground and anchored with a wooden stake.
Sediment Control Logs can be used as perimeter control for stockpiles, as check dams in
small drainage ways (e.g., swales) or on disturbed slopes to shorten flow lengths. If the
wattles are weighted, they can be used as part of an Inlet Protection (IP) design (see
above).
Sediment Control Logs should be inspected for excess sediment accumulation. The sediment
should be removed prior to reaching half the height of the log.
At a minimum, Sediment Control Logs should be used around soil stockpiles and for inlet
protection in unpaved areas of the site (see above). Straw wattles are proposed along the
downstream edge of the proposed landscaped areas. These locations will prevent sediment
from the spilling into the concrete parking area and surrounding street, mobilizing and
draining into the existing and proposed storm drain systems.
Rock Socks (Phases I - IV)
Rock Socks are proposed along the west curbline of Mason Street to reduce the velocity of
water leaving the project site and introduce another opportunity for sediment removal. Rock
Sock heights should allow for pools to develop upstream, creating minor backwaters to both
reduce velocities and to allow sediment deposition. The rock socks should be spaced so that
the top of each dam is equal in elevation to the toe of the next upstream check dam.
Rock socks should be inspected regularly for gaps or holes which would allow water to pass
through the structures untreated. The accumulated sediment should be removed and
typically prior to the sediment depth reaching half the height of the check dam.
Concrete Washout Area (Phases II - III)
A concrete washout area may be provided on-site. The washout can be lined or unlined
excavated pits in the ground, commercially manufactured prefabricated containers, or above
the ground holding areas. The concrete washout must be located a minimum of 400 feet
from any natural drainage way or body of water, and at least 1000 feet from any wells or
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Erosion Control Report 7
drinking water sources. Washout areas should not be located in an area where shallow
groundwater may be present. The contractor shall place a Vehicle Tracking Pad if the
selected location for the Concrete Washout Area is detached from pavement. Clear signage
identifying the concrete washout should also be provided.
The Concrete Washout Area should be inspected regularly. Particular attention should be
paid to signage to ensure that the area is clearly marked. Confirmation that the washout is
being used should also be noted to ensure that other undesignated areas of the site are not
being used incorrectly as a concrete washout.
Permanent/Established Vegetation (Phase IV)
Permanent or established vegetation and landscaping is considered a permanent form of
sediment and erosion control. Areas where the previous conditions apply will contain
sufficient permanent BMPs such as sod or landscape material (e.g., smooth river
rock/cobble and wood mulch).
3.3 Non-Structural Practices for Erosion and Sediment Control
Non-Structural BMPs are practices or activities that are implemented to prevent erosion from
occurring or limit its effects. These BMPs can be a practice resulting in physical changes to the site,
such as mulching or slope stabilization. They can also result in behavioral changes on the site, such
as changes to construction phasing to minimize exposure to weather elements, or increased
employee awareness gained through training.
Good Housekeeping Practices (Phases I -IV)
Good housekeeping practices that will prevent pollution associated with solid, liquid, and
hazardous construction-related materials and wastes should be implemented throughout the
project. Examples of good housekeeping include providing an appropriate location for waste
management containers, establishing proper building material staging areas, establishing
proper equipment/vehicle fueling and maintenance practices.
Street Sweeping (Phases I -IV)
Street sweeping should be used to remove sediment that has been tracked onto adjacent
roadways. Roadways should be inspected at least once a day, and sediment should be
removed as needed. A check of the area inlet protection should be completed after sweeping
to ensure nothing was displaced during sweeping operations. Street sweeping can reduce
the sediment washed into the existing storm drain system. Street sweeping may be
necessary on the existing hardscape areas which receive runoff from the disturbed areas.
Saw Cutting Pollution Prevention (Phase II)
The following protocol is recommended to prevent dust and slurry from asphalt and concrete
saw cutting activities from migrating into the existing storm drain system.
- Slurry and cuttings shall be vacuumed during cutting and surfacing operations
- Slurry and cuttings shall not remain on permanent concrete or asphalt pavement
overnight
- Slurry and cuttings shall not drain to any natural or constructed drainage
conveyance
- Collected slurry and cuttings shall be disposed of in a manner that does not violate
groundwater or surface water standards
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Erosion Control Report 8
3.4 Phased BMP Installation
It is important to recognize the four (4) major Development Phases as defined by the State of
Colorado’s Stormwater Discharge Permit (SDP). These four development phases (referred to as
Sequencing by the City of Fort Collins) have been distinguished to aid in the appropriate timing of
installation/implementation of BMPs at different stages of the construction process. These phases
are described as follows:
Phase I – Grading Stage; BMPs for initial installation of perimeter controls
Phase II – Infrastructure Stage; BMPs for utility, paving and curb installation
Phase III – Vertical Construction Stage; BMPs for individual building construction.
Phase IV – Permanent BMPs and final site stabilization.
The following is a rough estimate of the anticipated construction sequence for site improvements.
The schedule outlined below is subject to change as the project progresses and as determined by
the contractor.
Table 1 - Construction Schedule
TASK BEGINNING
DATE ENDING DATE
BMP - PHASE OF
DEVELOPMENT
Building Permit TBD TBD I
Removal of Existing Improvements TBD TBD I
Utility Installation TBD TBD II
Building Construction TBD TBD III
Final Stabilization TBD TBD IV
3.5 Material Handling and Spill Prevention
Potential pollution sources, as discussed in earlier sections, are to be to be identified by the
contractor. Spill prevention procedures are to be determined and put in place prior to construction
by the contractor. A spill and flooding response procedure must also be determined and put in place
prior to construction by the contractor. Additionally, steps should be taken to reduce the potential
for leaks and spills to come in contact with stormwater runoff, such as storing and handling toxic
materials in covered areas or by storing chemicals within berms or other secondary containment
devices.
A notification procedure must be put in place by the contractor, by which workers would first notify
the site construction superintendent. Depending on the severity of the spill, the site construction
superintendent would possibly notify the Colorado Department of Public Health and Environment -
Water Quality Control Division, downstream water users or other appropriate agencies. The release
of any chemical, oil, petroleum product, sewage, etc., which enter waters of the State of Colorado
(which include surface water, ground water and dry gullies or storm sewers leading to surface
water) must be reported immediately to the Division’s emergency spill reporting line at (877)
518-5608. All spills that will require cleanup, even if the spill is minor and does not need to be
reported to the state, should still be reported to the City of Fort Collins Utilities office at 970-221-
6700.
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Erosion Control Report 9
3.6 Waste Management and Disposal
Any waste material that currently exists on the site or that is generated by construction will be
disposed of in such a manner as to not cause pollutants in stormwater discharges. If waste is to be
stored on-site, it shall be in an area located a minimum of 100 feet from all drainage courses.
Whenever waste is not stored in a non-porous container, it shall be in an area enclosed by a 12-
inch high compacted earthen ridge or some other approved secondary containment device. The area
shall be covered with a non-porous lining to prevent soil contamination. Whenever precipitation is
predicted, the waste shall be covered with a non-porous cover, anchored on all sides to prevent its
removal by wind and to prevent precipitation from leaching out potential pollutants from the waste.
On-site waste disposal practices, such as dumpsters, should be covered or otherwise contained as
to prevent dispersion of waste materials from wind. It shall also be the responsibility of the
Contractor to maintain a clean jobsite to prevent dispersion of waste material and potential
pollutants into adjacent properties or waterways.
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Erosion Control Report 10
4.0 Final Stabilization and Long-Term Stormwater Management
4.1 Final Stabilization
All disturbed areas will be seeded, crimped and mulched. Soil amendments such as compost, peat,
aged manure, or other similar materials, shall also be utilized. Soil amendments shall be tilled into
the soil to a minimum depth of 6”, and should comply with the requirements found in City Code
Section 12-132 (refer also to Land Use Code 3.8.21). As defined by the Colorado Department of
Public Health and Environment (CDPHE) in the General Permit Application for Stormwater
Discharges, “Final stabilization is reached when all soil disturbing activities at the site have been
completed, and uniform vegetative cover has been established with a density of at least 70 percent
of pre-disturbance levels or equivalent permanent, physical erosion reduction methods have been
employed.”
Table 2 – Native Grass Seed Mix
Preferred
Varieties
Seeded Rate
(lbs. per acre,
drilled)
PLS
Seeded/acre
Leymus Cinereus Great Basin Wilrye Mangar 3 285,000
Nassella Viridula Green Needlegrass Lodorm 2 362,000
Chnatherum Hymenoides Indian Ricegrass Paloma, Nezpar 1 188,000
Elymus Trachycaulus Slender Wheatgrass Primar, Revenue 2 320,000
Elymus Lanceolatus Thickspike Wheatgrass Critana 3 580,500
Pascopyrum Smithii Western Wheatgrass Arriba, Barton 4 504,000
Totals 15 2,239,500
Species
4.2 Long-Term Stormwater Management
The primary method of long-term stormwater management will remain unchanged following
completion of the proposed improvements.
Any waste material that currently exists on the site or that is generated by construction will be
disposed of in such a manner as to not cause pollutants in stormwater discharges. If waste is to be
stored on-site, it shall be in an area located a minimum of 100 feet from all drainage courses.
Whenever waste is not stored in a non-porous container, it shall be in an area enclosed by a 12-
inch high compacted earthen ridge or some other approved secondary containment device. The area
shall be covered with a non-porous lining to prevent soil contamination. Whenever precipitation is
predicted, the waste shall be covered with a non-porous cover, anchored on all sides to prevent its
removal by wind and to prevent precipitation from leaching out potential pollutants from the waste.
On-site waste disposal practices, such as dumpsters, should be covered or otherwise contained as
to prevent dispersion of waste materials from wind. It shall also be the responsibility of the
contractor to maintain a clean jobsite to prevent dispersion of waste material and potential
pollutants into adjacent properties or waterways.
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Erosion Control Report 11
5.0 Inspection and Maintenance
5.1 BMP Inspection
All temporary erosion control facilities shall be inspected at a minimum of once every two weeks
and after each significant storm event or snowmelt. Repairs or reconstruction of BMPs, as
necessary, shall occur as soon as possible in order to ensure the continued performance of their
intended function.
The construction site perimeter, disturbed areas, all applicable/installed erosion and sediment
control measures, and areas used for material storage that are exposed to precipitation shall be
inspected for evidence of, or the potential for, pollutants entering the drainage system. Erosion and
sediment control measures identified herein shall be observed to ensure that they are operating
correctly. Particular attention should be paid to areas that have a significant potential for
stormwater pollution, such as demolition areas and vehicle entries to the site.
5.2 BMP Maintenance
Any BMPs not operating in accordance with this Erosion Control Report must be addressed as soon
as possible to prevent the discharge of pollutants.
Preventative maintenance of all temporary and permanent erosion control BMPs shall be provided
in order to ensure the continued performance of their intended function. Temporary erosion control
measures are to be removed after the site has been sufficiently stabilized as determined by the City
of Fort Collins. Maintenance activities and actions to correct problems shall be noted and recorded
during inspections.
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Erosion Control Report 12
References
1. Geotechnical Subsurface Exploration Report Proposed 5-Story Mixed Use Building 203 West
Mulberry Street Fort Collins, Colorado, December 3, 2012, Earth Engineering Consultants,
Inc. (EEC Project No. 1122094).
2. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control
District, Water Resources Publications, LLC., Denver, Colorado, Updated November 2010.
APPENDIX A
EROSION CONTROL PLAN | STATIC AND DYNAMIC SITE PLANS
MAX Flats
Project Number: 860-001 Location: Fort Collins, CO
Date: April 23, 2013 Total Acres: 0.70
EROSION CONTROL MEASURE Units
Estimated
Quantity
Unit
Price
Total
Price
L.F. 150 $1.85 $277.50
each 50 $20.00 $1,000.00
each 1 $75.00 $75.00
Aea Inlet Protection | Mirafi Dandy Sack each 1 $75.00 $75.00
Curb Inlet Protection (w/o grate) each 0 $75.00 $0.00
Curb Inlet Protection (w/grate) each 2 $100.00 $200.00
Rock Sock each 4 $25.00 $100.00
Vehicle Tracking Control Pad each 1 $700.00 $700.00
L.F. 130 $1.00 $130.00
per hour 0 $70.00 $0.00
acre 0.70 $1,325.00 $927.50
Sub-Total: $3,485.00
1.5 x Sub-Total: $5,227.50
Amount of security: $5,227.50
Total Acres x $1325/acre: $927.50
Sub-Total: $927.50
1.5 x Sub-Total: $1,391.25
Cost to Re-seed: $1,050.00
Minimum escrow amount: $3,000.00
Erosion Control Escrow: $5,227.50
NOTE: 'Total Acres' represents total disturbed area.
Area Inlet Protection
Option 3 | Miniumum Escrow Amount
Final Escrow Amount
MAX Flats
Erosion Control Cost Estimate
Vegetate Landscaped Areas
Option 1 | BMP Costs
Silt Fence
Sawcutting Pollution Prevention
Street Sweeping and Cleaning
Option 2 | Cost to Re-seed Disturbed acreage
Straw Wattles (9" x 10' dimension)
4/23/2013 9:22 AM D:\Projects\860-001\Drainage\Erosion\860-001_Erosion-Escrow-Estimate
APPENDIX B
EROSION CONTROL DETAILS
Chapter 7 Construction BMPs
November 2010 Urban Drainage and Flood Control District 7-13
Urban Storm Drainage Criteria Manual Volume 3
Final Stabilization
▪ Revegetate Site
▪ Activate Post Construction BMPs
(e.g., convert sediment basin to extended
detention basin)
▪ Remove Temporary BMPs
▪ Closeout State and Local Stormwater Permits
Construction Phase
Representative Phases:
▪ Clearing and Grubbing
▪ Rough Grading
▪ Road Construction
▪ Utility and Infrastructure Installation
▪ Vertical Construction (Buildings)
▪ Final Grading
Management Practices:
▪ Phase Construction Activities to Minimize
Disturbed Area at a Given Time
▪ Sequence Contruction within Phases to Avoid
Idle Disturbed Areas
▪ Install, Inspect and Proactively Maintain BMPs
Appropriate for Each Phase of Construction
▪ Maintain and Update SWMP as Construction
Progresses
Pre-Construction
▪ Develop Site Plan
▪ Obtain Site Survey, Hydrology and Soils
Information
▪ Prepare SWMP
▪ Obtain Stormwater Construction Permits
(State and Local)
▪ Obtain Other Relevant Permits
(e.g., 404 , Floodplain, Dewatering)
Figure 7-2. Construction Stormwater Management
Construction BMPs Construction BMPs
7-14 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Functions
Erosion
Control
Sediment
Control
Site/Material
Management
Surface Roughening Yes No No
Temporary/Permanent Seeding Yes No No
Soil Binders Yes No Moderate
Mulching Yes Moderate No
Compost Blankets and Filter Berms Yes Moderate No
Rolled Erosion Control Products Yes No No
Temporary Slope Drains Yes No No
Temporary Outlet Protection Yes Moderate No
Rough Cut Street Control Yes Moderate No
Earth Dikes / Drainage Swales Yes Moderate No
Terracing Yes Moderate No
Check Dams Yes Moderate No
Streambank Stabilization Yes No No
Wind Erosion / Dust Control Yes No Moderate
Silt Fence No Yes No
Sediment Control Log Moderate Yes No
Straw Bale Barrier No Moderate No
Brush Barrier Moderate Moderate No
Rock Sock (perimeter control) No Yes No
Inlet Protection (various forms) No Yes No
Sediment Basins No Yes No
Sediment Traps No Yes No
Vegetative Buffers Moderate Yes Yes
Chemical Treatment Moderate Yes No
Concrete Washout Area No No Yes
Stockpile Management Yes Yes Yes
Good Houskeeping (multiple practices) No No Yes
Construction Phasing Moderate Moderate Yes
Protection of Existing Vegetation Yes Moderate Yes
Construction Fence No No Yes
Vehicle Tracking Control Moderate Yes Yes
Stabilized Construction Roadway Yes Moderate Yes
Stabilized Staging Area Yes Moderate Yes
Street Sweeping / Vacuuming No Yes Yes
Temporary Diversion Channel Yes No No
Dewatering Operations Moderate Yes Yes
Temporary Stream Crossing Yes Yes No
Temporary Batch Plants No No Yes
Paving and Grinding Operations No No Yes
Site Management and Other Specific Practices
Sediment Control BMPs
Erosion Control BMPs
Materials Management
Table 7-2. Overview of Construction BMPs
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.
Wind Erosion/Dust Control (DC) EC-14
November 2010 Urban Drainage and Flood Control District DC-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph DC-1. Water truck used for dust suppression. Photo
courtesy of Douglas County.
Description
Wind erosion and dust control BMPs
help to keep soil particles from entering
the air as a result of land disturbing
construction activities. These BMPs
include a variety of practices generally
focused on either graded disturbed areas
or construction roadways. For graded
areas, practices such as seeding and
mulching, use of soil binders, site
watering, or other practices that provide
prompt surface cover should be used.
For construction roadways, road
watering and stabilized surfaces should
be considered.
Appropriate Uses
Dust control measures should be used on any site where dust poses a problem to air quality. Dust control
is important to control for the health of construction workers and surrounding waterbodies.
Design and Installation
The following construction BMPs can be used for dust control:
An irrigation/sprinkler system can be used to wet the top layer of disturbed soil to help keep dry soil
particles from becoming airborne.
Seeding and mulching can be used to stabilize disturbed surfaces and reduce dust emissions.
Protecting existing vegetation can help to slow wind velocities across the ground surface, thereby
limiting the likelihood of soil particles to become airborne.
Spray-on soil binders form a bond between soil particles keeping them grounded. Chemical
treatments may require additional permitting requirements. Potential impacts to surrounding
waterways and habitat must be considered prior to use.
Placing rock on construction roadways and entrances will help keep dust to a minimum across the
construction site.
Wind fences can be installed on site to reduce wind
speeds. Install fences perpendicular to the prevailing
wind direction for maximum effectiveness.
Maintenance and Removal
When using an irrigation/sprinkler control system to aid in
dust control, be careful not to overwater. Overwatering will
cause construction vehicles to track mud off-site.
Wind Erosion Control/
Dust Control
Functions
Erosion Control Yes
Sediment Control No
Site/Material Management Moderate
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
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
Sediment Control Log (SCL) SC-2
November 2010 Urban Drainage and Flood Control District SCL-1
Urban Storm Drainage Criteria Manual Volume 3
Photographs SCL-1 and SCL-2. Sediment control logs used as 1) a
perimeter control around a soil stockpile; and, 2) as a "J-hook"
perimeter control at the corner of a construction site.
Description
A sediment control log is a linear roll
made of natural materials such as
straw, coconut fiber, or other fibrous
material trenched into the ground and
held with a wooden stake. Sediment
control logs are also often referred to
as "straw wattles." They are used as a
sediment barrier to intercept sheet flow
runoff from disturbed areas.
Appropriate Uses
Sediment control logs can be used in
the following applications to trap
sediment:
As perimeter control for stockpiles
and the site.
As part of inlet protection designs.
As check dams in small drainage
ditches. (Sediment control logs
are not intended for use in
channels with high flow
velocities.)
On disturbed slopes to shorten flow
lengths (as an erosion control).
As part of multi-layered perimeter control along a receiving water such as a stream, pond or wetland.
Sediment control logs work well in combination with other layers of erosion and sediment controls.
Design and Installation
Sediment control logs should be installed along the contour to avoid concentrating flows. The maximum
allowable tributary drainage area per 100 lineal feet of sediment control log, installed along the contour, is
approximately 0.25 acres with a disturbed slope length of up to 150 feet and a tributary slope gradient no
steeper than 3:1. Longer and steeper slopes require additional measures. This recommendation only
applies to sediment control logs installed along the contour. When installed for other uses, such as
perimeter control, it should be installed in a way that will not
produce concentrated flows. For example, a "J-hook"
installation may be appropriate to force runoff to pond and
evaporate or infiltrate in multiple areas rather than concentrate
and cause erosive conditions parallel to the BMP.
Sediment Control Log
Functions
Erosion Control Moderate
Sediment Control Yes
Site/Material Management No
SC-2 Sediment Control Log (SCL)
SCL-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Although sediment control logs initially allow runoff to flow through the BMP, they can quickly become
a barrier and should be installed is if they are impermeable.
Design details and notes for sediment control logs are provided in Detail SCL-1. Sediment logs must be
properly trenched and staked into the ground to prevent undercutting, bypassing and displacement. When
installed on slopes, sediment control logs should be installed along the contours (i.e., perpendicular to
flow).
Improper installation can lead to poor performance. Be sure that sediment control logs are properly
trenched, anchored and tightly jointed.
Maintenance and Removal
Be aware that sediment control logs will eventually degrade. Remove accumulated sediment before the
depth is one-half the height of the sediment log and repair damage to the sediment log, typically by
replacing the damaged section.
Once the upstream area is stabilized, remove and properly dispose of the logs. Areas disturbed beneath
the logs may need to be seeded and mulched. Sediment control logs that are biodegradable may
occasionally be left in place (e.g., when logs are used in conjunction with erosion control blankets as
permanent slope breaks). However, removal of sediment control logs after final stabilization is typically
recommended when used in perimeter control, inlet protection and check dam applications.
Sediment Control Log (SCL) SC-2
November 2010 Urban Drainage and Flood Control District SCL-3
Urban Storm Drainage Criteria Manual Volume 3
SC-2 Sediment Control Log (SCL)
SCL-4 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Sediment Control Log (SCL) SC-2
November 2010 Urban Drainage and Flood Control District SCL-5
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
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
Inlet Protection (IP) SC-6
November 2010 Urban Drainage and Flood Control District IP-7
Urban Storm Drainage Criteria Manual Volume 3
INSTALLATION GUIDELINES
Remove grate from frame and slip into Dandy
Bag®. Tuck the enclosure flap inside to
completely enclose the grate. Holding the lifting
devices (do not rely on lifting devices to support
the entire weight of the grate), place the grate
into its frame.
DANDY SACK™
The Dandy Sack™ is an open-top bag that is
designed to hang underneath a storm grate to
filter sediment-laden stormwater.
The Difference Dandy Sack™ Makes:
• Easy installation. No rebar required.
• Internal straps cradle grate for added
security when installing & removing.
• 2ft. containment area is very manageable.
• Available in 3 standard sizes.
• Available with optional oil absorbents.
• Available with patented curb blocking
technology, Dandy Curb Sack.™
INSTALLATION GUIDELINES
Remove the grate from catch basin and stand on
end. Move the top lifting straps out of the way
and place the grate into the Dandy Sack™ so that
Dandy Drop Inlet Protection
Flat Grate and Mountable Curb Inlet Protection
OUR COMPANY
TenCate develops and produces materials that
function to increase performance, reduce costs
and deliver measurable results by working with
our customers to provide advanced solutions.
Dandy Products exclusively by TenCate
Geosynthetics have an engineered design in
which suspended solids are allowed to settle
out of the slowed flow and are captured prior
to entering the inlet.
OUR PRODUCTS
DANDY BAG®
The patented Dandy Bag® is designed for use
with flat grates (including round) and mountable
curbs to filter sediment-laden storm water.
The Difference Dandy Bag® Makes:
• Unique patented design keeps silt, sediment
and debris out of storm systems.
• Reduces the need to flush/clean inlets.
• Fabricated from orange geotextile.
• Easy to install, inspect, and re-use.
• Reduces outflow turbidity.
the grate is below the top straps and above the
lower straps. Holding the lifting straps, insert
the grate into the inlet.
DANDY POP™
The Dandy Pop™ is designed for use with flat
field grates to filter sediment-laden water. The
Dandy Pop™ fully encloses the grate, virtually
eliminating sediment infiltration.
The Difference Dandy Pop™ Makes:
• Unique patented design keeps silt,
sediment and debris out of storm systems.
• Easily visible to machine operators in the field.
Property Test Method Units Marv
Grab Tensile Strength (MD x CD)
Grab Tensile Elongation
Puncture Strength
Mullen Burst Strength
Trapezoid Tear Strength (MD x CD)
Percent Open Area (POA)
Apparent Opening Size (AOS)
Permittivity
Permeability
Water Flow Rate
Ultraviolet Resistance
Color
ASTM D 4632
ASTM D 4632
ASTM D 4833
ASTM D 3786
ASTM D 4533
COE -22125-86
ASTM D 4751
ASTM D 4491
ASTM D 4491
ASTM D 4491
ASTM D 4355
1.62 (365) x 0.89 (200)
24 x 10
0.40 (90)
3097 (450)
0.51 (115) x 0.33 (75)
10
0.425 (40)
2.1
0.14
5907 (145)
90
Orange1
kN (lbs)
%
kN (lbs)
kPa (psi)
kN (lbs)
%
mm (US Std Sieve)
sec-1
cm/sec
l/min/m2 (gal/min/ft2)
%
Technical Data for FW® 402 Geotextile
1The orange color geotextile is a trademark of Dandy Products, Inc. US Patent No. 5,725,782, 6,010,622, & 6,749,366
Dandy Drop Inlet Protection
Flat Grate and Mountable Curb Inlet Protection
365 South Holland Drive
Pendergrass, GA 30567
Tel 800 685 9990
Tel 706 693 2226
Fax 706 693 4400
www.mirafi.com
PDS.DROP0508
TenCateTM Geosynthetics North America does not assume liability for the accuracy or completeness of this information or for the ultimate use by the purchaser. TenCateTM Geosynthetics
North America disclaims
Protection of Existing Vegetation (PV) SM-2
November 2010 Urban Drainage and Flood Control District PV-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph PV-1. Protection of existing vegetation and a sensitive
area. Photo courtesy of CDOT.
Description
Protection of existing vegetation on a
construction site can be accomplished
through installation of a construction
fence around the area requiring protection.
In cases where upgradient areas are
disturbed, it may also be necessary to
install perimeter controls to minimize
sediment loading to sensitive areas such as
wetlands. Existing vegetation may be
designated for protection to maintain a
stable surface cover as part of construction
phasing, or vegetation may be protected in
areas designated to remain in natural
condition under post-development
conditions (e.g., wetlands, mature trees,
riparian areas, open space).
Appropriate Uses
Existing vegetation should be preserved for the maximum practical duration on a construction site
through the use of effective construction phasing. Preserving vegetation helps to minimize erosion and
can reduce revegetation costs following construction.
Protection of wetland areas is required under the Clean Water Act, unless a permit has been obtained from
the U.S. Army Corps of Engineers (USACE) allowing impacts in limited areas.
If trees are to be protected as part of post-development landscaping, care must be taken to avoid several
types of damage, some of which may not be apparent at the time of injury. Potential sources of injury
include soil compaction during grading or due to construction traffic, direct equipment-related injury such
as bark removal, branch breakage, surface grading and trenching, and soil cut and fill. In order to
minimize injuries that may lead to immediate or later death of the tree, tree protection zones should be
developed during site design, implemented at the beginning of a construction project, as well as continued
during active construction.
Design and Installation
General
Once an area has been designated as a preservation area, there should be no construction activity allowed
within a set distance of the area. Clearly mark the area with construction fencing. Do not allow
stockpiles, equipment, trailers or parking within the
protected area. Guidelines to protect various types of
existing vegetation follow.
Protection of Existing Vegetation
Functions
Erosion Control Yes
Sediment Control Moderate
Site/Material Management Yes
SM-2 Protection of Existing Vegetation (PV)
PV-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Surface Cover During Phased Construction
Install construction fencing or other perimeter controls around areas to be protected from clearing and
grading as part of construction phasing.
Maintaining surface cover on steep slopes for the maximum practical duration during construction is
recommended.
Open Space Preservation
Where natural open space areas will be preserved as part of a development, it is important to install
construction fencing around these areas to protect them from compaction. This is particularly important
when areas with soils with high infiltration rates are preserved as part of LID designs. Preserved open
space areas should not be used for staging and equipment storage.
Wetlands and Riparian Areas
Install a construction fence around the perimeter of the wetland or riparian (streamside vegetation) area to
prevent access by equipment. In areas downgradient of disturbed areas, install a perimeter control such as
silt fence, sediment control logs, or similar measure to minimize sediment loading to the wetland.
Tree Protection
1
Before beginning construction operations, establish a tree protection zone around trees to be
preserved by installing construction fences. Allow enough space from the trunk to protect the root
zone from soil compaction and mechanical damage, and the branches from mechanical damage (see
Table PV-1). If low branches will be kept, place the fence outside of the drip line. Where this is not
possible, place fencing as far away from the trunk as possible. In order to maintain a healthy tree, be
aware that about 60 percent of the tree's root zone extends beyond the drip line.
Table PV-1
Guidelines for Determining the Tree Protection Zone
(Source: Matheny and Clark, 1998; as cited in GreenCO and WWE 2008)
Distance from Trunk (ft) per inch of DBH
Species Tolerance to Damage Young Mature Over mature
Good 0.5' 0.75' 1.0'
Moderate 0.75' 1.0' 1.25'
Poor 1.0' 1.25' 1.5'
Notes: DBH = diameter at breast height (4.5 ft above grade); Young = <20% of
life expectancy; Mature = 20%-80% of life expectancy; Over mature =>80% of
life expectancy
Most tree roots grow within the top 12 to 18 inches of soil. Grade changes within the tree protection
zone should be avoided where possible because seemingly minor grade changes can either smother
1 Tree Protection guidelines adapted from GreenCO and WWE (2008). Green Industry Best Management Practices (BMPs) for
the Conservation and Protection of Water Resources in Colorado: Moving Toward Sustainability, Third Release. See
www.greenco.org for more detailed guidance on tree preservation.
Protection of Existing Vegetation (PV) SM-2
November 2010 Urban Drainage and Flood Control District PV-3
Urban Storm Drainage Criteria Manual Volume 3
roots (in fill situations) or damage roots (in cut situations). Consider small walls where needed to
avoid grade changes in the tree protection zone.
Place and maintain a layer of mulch 4 to 6-inch thick from the tree trunk to the fencing, keeping a
6-inch space between the mulch and the trunk. Mulch helps to preserve moisture and decrease soil
compaction if construction traffic is unavoidable. When planting operations are completed, the mulch
may be reused throughout planting areas.
Limit access, if needed at all, and appoint one route as the main entrance and exit to the tree
protection zone. Within the tree protection zone, do not allow any equipment to be stored, chemicals
to be dumped, or construction activities to take place except fine grading, irrigation system
installation, and planting operations. These activities should be conducted in consultation with a
landscaping professional, following Green Industry BMPs.
Be aware that soil compaction can cause extreme damage to tree health that may appear gradually
over a period of years. Soil compaction is easier to prevent than repair.
Maintenance and Removal
Repair or replace damaged or displaced fencing or other protective barriers around the vegetated area.
If damage occurs to a tree, consult an arborist for guidance on how to care for the tree. If a tree in a
designated preservation area is damaged beyond repair, remove and replace with a 2-inch diameter tree of
the same or similar species.
Construction equipment must not enter a wetland area, except as permitted by the U.S. Army Corps of
Engineers (USACE). Inadvertent placement of fill in a wetland is a 404 permit violation and will require
notification of the USACE.
If damage to vegetation occurs in a protected area, reseed the area with the same or similar species,
following the recommendations in the USDCM Revegetation chapter.
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
Street Sweeping and Cleaning S-11
November 2010 Urban Drainage and Flood Control District SWC-1
Urban Storm Drainage Criteria Manual Volume 3
Photograph SSC-1. Monthly street sweeping from April through
November removed nearly 40,690 cubic yards of sediment/debris from
Denver streets in 2009. Photo courtesy of Denver Public Works.
Description
Street sweeping uses mechanical pavement
cleaning practices to reduce sediment,
litter and other debris washed into storm
sewers by runoff. This can reduce
pollutant loading to receiving waters and
in some cases reduce clogging of storm
sewers and prolong the life of infiltration
oriented BMPs and reduce clogging of
outlet structures in detention BMPs.
Different designs are available with typical
sweepers categorized as a broom and
conveyor belt sweeper, wet or dry
vacuum-assisted sweepers, and
regenerative-air sweepers. The
effectiveness of street sweeping is
dependent upon particle loadings in the
area being swept, street texture, moisture
conditions, parked car management,
equipment operating conditions and
frequency of cleaning (Pitt et al. 2004).
Appropriate Uses
Street sweeping is an appropriate technique in urban areas where sediment and litter accumulation on
streets is of concern for aesthetic, sanitary, water quality, and air quality reasons. From a pollutant
loading perspective, street cleaning equipment can be most effective in areas where the surface to be
cleaned is the major source of contaminants. These areas include freeways, large commercial parking
lots, and paved storage areas (Pitt et al. 2004). Where significant sediment accumulation occurs on
pervious surfaces tributary to infiltration BMPs, street sweeping may help to reduce clogging of
infiltration media. In areas where construction activity is occurring, street sweeping should occur as part
of construction site stormwater management plans. Vacuuming of permeable pavement systems is also
considered a basic routine maintenance practice to maintain the BMP in effective operating condition.
See the maintenance chapter for more information on permeable pavement systems. Not all sweepers are
appropriate for this application.
Practice Guidelines1
1. Post street sweeping schedules with signs and on local government websites so that cars are not
parked on the street during designated sweeping days.
2. Sweeping frequency is dependent on local government budget, staffing, and equipment availability,
but monthly sweeping during non-winter months is a common approach in the metro Denver urban
1 Practice guidelines adapted from CASQA (2003) California Stormwater BMP Handbook, Practice SC-70 Road and Street
Maintenance.
S-11 Street Sweeping and Cleaning
SWC-2 Urban Drainage and Flood Control District November 2010
Urban Storm Drainage Criteria Manual Volume 3
Changes in Street Sweeper Technology (Source: Center for Watershed Protection 2002)
At one time, street sweepers were thought to have great potential to remove stormwater pollutants from
urban street surfaces and were widely touted as a stormwater treatment practice in many communities.
Street sweeping gradually fell out of favor, largely as a result of performance monitoring conducted as
part of the National Urban Runoff Program (NURP). These studies generally concluded that street
sweepers were not very effective in reducing pollutant loads (USEPA, 1983). The primary reason for
the mediocre performance was that mechanical sweepers of that era were unable to pick up fine-grained
sediment particles that carry a substantial portion of the stormwater pollutant load. In addition, the
performance of sweepers is constrained by that portion of a street’s stormwater pollutant load delivered
from outside street pavements (e.g., pollutants that wash onto the street from adjacent areas or are
directly deposited on the street by rainfall). Street sweeping technology, however, has evolved
considerably since the days of the NURP testing. Today, communities have a choice in three basic
sweeping technologies to clean their urban streets: traditional mechanical sweepers that utilize a broom
and conveyor belt, vacuum-assisted sweepers, and regenerative-air sweepers (those that blast air onto
the pavement to loosen sediment particles and vacuum them into a hopper).
For more information, see
http://www.cwp.org/Resource_Library/Center_Docs/PWP/ELC_PWP121.pdf
area. Consider increasing sweeping frequency based on factors such as traffic volume, land use, field
observations of sediment and trash accumulation, proximity to watercourses, etc. For example:
Increase the sweeping frequency for streets with high pollutant loadings, especially in high traffic
and industrial areas.
Conduct street sweeping prior to wetter seasons to remove accumulated sediments.
Increase the sweeping frequency for streets in special problem areas such as special events, high
litter or erosion zones.
3. Perform street cleaning during dry weather if possible.
4. Avoid wet cleaning the street; instead, utilize dry methods where possible.
5. Maintain cleaning equipment in good working condition and purchase replacement equipment as
needed. Old sweepers should be replaced with more technologically advanced sweepers (preferably
regenerative air sweepers) that maximize pollutant removal.
6. Operate sweepers at manufacturer recommended optimal speed levels to increase effectiveness.
7. Regularly inspect vehicles and equipment for leaks and repair promptly.
8. Keep accurate logs of the number of curb-miles swept and the amount of waste collected.
9. Dispose of street sweeping debris and dirt at a landfill.
10. Do not store swept material along the side of the street or near a storm drain inlet.
Clearing & Grading Development Standards Page 123
Source: http://www.ci.bellevue.wa.us/pdf/Development%20Services/CG_DevStds2010_BMPC152.pdf
BMP C152: Sawcutting and Surfacing Pollution Prevention SPP
Purpose Sawcutting and surfacing operations generate slurry and process water
that contains fine particles and high pH (concrete cutting), both of which
can violate the water quality standards in the receiving water. This BMP
is intended to minimize and eliminate process water and slurry from
entering waters of the State.
Conditions of Use Anytime sawcutting or surfacing operations take place, these
management practices shall be utilized. Sawcutting and surfacing
operations include, but are not limited to, the following:
Sawing
Coring
Grinding
Roughening
Hydro-demolition
Bridge and road surfacing
Design and
Installation
Specifications
Slurry and cuttings shall be vacuumed during cutting and surfacing
operations.
Slurry and cuttings shall not remain on permanent concrete or asphalt
pavement overnight.
Slurry and cuttings shall not drain to any natural or constructed
drainage conveyance.
Collected slurry and cuttings shall be disposed of in a manner that does
not violate groundwater or surface water quality standards.
Process water that is generated during hydro-demolition, surface
roughening or similar operations shall not drain to any natural or
constructed drainage conveyance and shall be disposed of in a manner
that does not violate groundwater or surface water quality standards.
Cleaning waste material and demolition debris shall be handled and
disposed of in a manner that does not cause contamination of water. If
the area is swept with a pick-up sweeper, the material must be hauled
out of the area to an appropriate disposal site.
Maintenance
Standards
Continually monitor operations to determine whether slurry, cuttings, or
process water could enter waters of the state. If inspections show that a
violation of water quality standards could occur, stop operations and
immediately implement preventive measures such as berms, barriers,
secondary containment, and vacuum trucks.
APPENDIX C
LANDSCAPE PLAN
any and all express, implied, statutory standards, warranties, guarantees, including without limitation any implied warranty as to merchantability or fitness for a particular purpose
or arising from a course of
dealing or usage of trade as to any equipment, materials, or information furnished herewith. This document should not be construed as engineering advice.
Mirafi® is a registered trademark of TenCateTM Geosynthetics North America.
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