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Construction Site
Soil Erosion and Sediment Control
Soil is a valuable natural resource that is vital to the
maintenance of the natural environment as we know it.
Everyday, hundreds of thousands of tons of unprotected soil are washed away by
erosion.
What is soil erosion?
Soil erosion is the detachment and movement of soil particles by water, wind,
ice, or gravity.
What is sediment?
Sediment is the result of erosion. Once soil particles have detached from the
surface, are transported from their site of origin and have come to rest on
other ground surfaces or in bodies of water, watercourses, or wetlands, they are
referred to as sediment.
Why be concerned about soil erosion and sediment control?
- It’s The Law: Soil erosion and sediment control
requirements are a part of several Federal and State regulations and may be
required by local ordinances as well.
- Surface Water Quality: Based on the most recent
IEPA Integrated
Water Quality Report (IEPA, 2006), 38% of Illinois’ streams
and more than 46% of lake acres assessed are adversely impacted by nonpoint
source pollutants (NPS). Urban runoff and construction site erosion have
been identified as significant sources of this pollution.
- Chemical Pollutants: Chemicals, such as some
pesticides, phosphorus, as well as toxicants and trace metals, can be
transported with sediment to receiving waters where they cause additional
damage to aquatic ecosystems.
- Construction Sites: Construction site erosion is a
significant source of sediment and other NPS pollutants. Soil erosion from a
construction site without proper soil erosion and sediment control practices
in place can average between 20-200 tons/acre/year--This is ten to twenty
times greater than typical soil losses on agricultural lands.
- Fish and Aquatic Plants: Suspended solids reduce
sunlight penetration needed for aquatic plants, reduce survival rates for
fish eggs, interfere with fish feeding habits, and clog and damage fish
gills which increases risk of infection and disease. Sediment deposits
destroy fish spawning areas, resulting in the loss of sensitive or
threatened fish species, adversely impact aquatic insects which are at the
base of the food chain, reduce channel capacity, and decrease the overall
quality of lakes, streams, and wetlands.
- Damage on Wetland Mitigation Sites: Findings from a
June 1998 Wetland Mitigation and Section 404 (of the Clean Water Act) Permit
Compliance Study conducted in the Chicago Region found that approximately
70% of permitted sites examined showed evidence of sediment accumulation
resulting from erosion. Active erosion entering mitigation sites was
observed on 14% of the permit sites. Other studies show sediment deposition
of less than 0.1 inch results in a 60-90% decrease in wetland seed
germination from new seedings or from wetland seed banks. Decreased species
diversity is also a result of sediment deposition, with less desirable
species often becoming prevalent.
What costs are associated with construction site erosion?
- Flooding: Sediment accumulation reduces stormwater
conveyance and storage functions of streams, wetlands, storm sewers,
detention basins, highway drainage ditches, and floodplains, which can
result in flooding.
- Water Treatment: Over time, municipal and industrial
water supply reservoirs lose storage capacity, navigable channels must
continually be dredged, and the cost of filtering and disposing of muddy
water in preparation for human or industrial use increases.
- Safety and Nuisance Issues: Sediment on roadways
creates potential safety issues and is a nuisance.
- Increased Construction Costs: Uncontrolled erosion and
sediment deposition increases construction costs. Sediment fills drainage
channels, detention basins and storm sewers and plugs culverts and storm
drainage systems, which then require frequent and costly maintenance.
Construction sites that are not effectively stabilized can cause serious
erosion problems that require regrading. Damage to new plantings on
mitigation sites or other areas often require replanting at a significant
cost.
- Negative Public Perception: The public often observes
muddy water leaving a construction site. Erosion and sediment control
measures may cost more up-front, but in the long-term are cost-effective.
Failure to comply with local, state, or federal law may result in
significant penalties. Environmental compliance problems can adversely
affect public perception.
What can be done to control soil erosion and provide sediment control?
- Preventative Action: Numerous studies show that it is
more cost effective and institutionally feasible to develop measures to
prevent or reduce pollutants in stormwater during new develop-ment than to
correct problems caused by these pollutants later.
- Establish Local Ordinances: Many counties and
municipalities have adopted soil erosion and sediment control ordinances
which, when consistently enforced and coordinated with state and federal
permit authorities, can be an extremely effective method to minimize damages
caused by erosion and sediment.
- Best Management Practices: Implementing appropriate
best management practices on construction sites protects and improves local
surface water resources and community infrastructure investments.
- Incorporate Soil Erosion and Sediment Control As An Integral
Part of Construction: Planning for soil erosion and sediment
control should be considered as important as any other component of the
development process. Proper implementation and maintenance of planned
practices will assure that costs incurred will be offset by economic,
environmental and other benefits.
Where to Get Help?
All agencies listed on this factsheet can provide guidance or referrals on
planning and implementing a successful soil erosion and sediment control
program. Call county level NRCS and SWCD offices who have field personnel to
assist in training and provide consultation in the selection of appropriate best
management practices. NRCS is listed in the phonebook under U.S. Government.
Visit the NRCS Home Page at:
www.il.nrcs.usda.gov
October 2007
NRCS Helping People Help the Land.
The U.S. Department of Agriculture (USDA)
prohibits discrimination in all its programs and activities on the basis of
race, color, national origin, age, disability, and where applicable, sex,
marital status, familial status, parental status, religion, sexual orientation,
genetic information, political beliefs, reprisal, or because all or a part of an
individual's income is derived from any public assistance program. (Not all
prohibited bases apply to all programs.) Persons with disabilities who require
alternative means for communication of program information (Braille, large
print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600
(voice and TDD). To file a complaint of discrimination write to USDA, Director,
Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C.
20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD).
A Printed Version of this fact sheet is available in
Adobe Acrobat
Format 6.0.
Construction Site - Soil Erosion and Sediment Control Fact Sheet
ConstSites2007FS.pdf (PDF, 178 kb)
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