Sediment control

A sediment control is a practice or device designed to keep eroded soil on a construction site, so that it does not wash off and cause water pollution to a nearby stream, river, lake, or bay. Sediment controls are usually employed together with erosion controls, which are designed to prevent or minimize erosion and thus reduce the need for sediment controls.

Commonly-used sediment controls

*Check dam
*Diversion dike
*Fiber rolls
*Sand bag barrier
*Sediment basin
*Sediment trap
*Silt fence
*Storm drain inlet protection
*Straw bale barrier
*Turbidity curtain [State of Washington. Department of Ecology. Olympia, WA. [http://www.ecy.wa.gov/programs/wq/stormwater/manual.html “Stormwater Management Manual for Western Washington.”] Volume II –Construction Stormwater Pollution Prevention. 2005.]

Active treatment systems

Chemical treatment of sediment, commonly called an active treatment system, is a relatively new form of sediment control for the construction industry. It is designed to reduce turbidity in nearby water bodies and involves collection of sediment-laden stormwater in a basin or tank, and adding a chemical flocculant. This causes the sediment to settle so it can be more easily removed from the water. Some of the flocculent chemicals used for sediment treatment are chitosan and polymers such as polyacrylamide. Chemical sediment control is currently used on some construction sites around the United States, typically larger sites where there is a high potential for damage to nearby streams. [ [http://www.casqa.org California Stormwater Quality Association.] Menlo Park, CA. [http://www.cabmphandbooks.com/Documents/Construction/SE-11.pdf “California Stormwater BMP Handbook: Chemical Treatment.”] Fact Sheet No. SE-11. January 2003.]

Regulatory requirements

All states in the U.S. have laws requiring installation of erosion and sediment controls (ESCs) on construction sites of a specified size. Federal regulations require ESCs on sites convert|1|acre|ha|abbr=on and larger. Smaller sites which are part of a common plan of development (e.g. a residential subdivision) are also required to have ESCs. [United States Environmental Protection Agency (EPA). [http://www.epa.gov/npdes/regulations/sw2-part1.pdf “Regulations for Revision of the Water Pollution Control Program Addressing Storm Water Discharges; Final Rule”] (Commonly called the “Phase II Stormwater Rule.”) "Federal Register," 64 FR 68721, December 8, 1999.] In some states, non-contiguous sites under convert|1|acre|m2|sing=on are also required to have ESCs. For example, the State of Maryland requires ESCs on sites of convert|5000|sqft|m2|abbr=on or more. [State of Maryland. "Code of Maryland Regulations (COMAR)." [http://www.dsd.state.md.us/comar/26/26.17.01.05.htm "Activities for Which Approved Erosion and Sediment Control Plans are Required."] Sec. 26.17.01.05.] The sediment controls must be installed before the beginning of land disturbance (i.e. land clearing, grubbing and grading) and must be maintained during the entire disturbance phase of construction.

ee also

*Geotechnical engineering
*Geotextile
*Nonpoint source pollution
*Stormwater
*Universal Soil Loss Equation

References

External links

* [http://www.erosioncontrol.com Erosion Control] - a trade magazine for the erosion control and construction industries
* [http://www.ieca.org International Erosion Control Association] - Professional Association, Publications, Training
* [http://www.epa.gov/npdes/pubs/sw_swppp_guide.pdf “Developing Your Stormwater Pollution Prevention Plan: A Guide for Construction Sites.”] - U.S. EPA