Perimeter Control Erosion Control Best Management Practice
Erosion control best management practices are required during all ground disturbing activity until permanent site ground covers are in place. A best management practice (BMP) is a physical, chemical, structural or managerial practice that prevents, reduces or treats contamination of water or which prevents or reduces soil erosion.
Perimeter control BMPs are the last protection before sediment enters the roadway, storm drains or adjacent properties. Perimeter control BMPs can be the most visible and most vandalized BMPs used on a site of ground disturbance. Perimeter BMPs shall be installed before starting and site grading activities.
Stormwater Control BMPs are:
- Sidewalk Subgrade Barrier
- Minimizes the transport of sediment from a construction site by using the sidewalk subgrade gravel as a temporary trap for sediment-laden runoff
- Temporary Sediment Control (Silt) Fences
- Divert or provide a barrier to surface flows and slow flows coming off a project
- Contain sediments onsite
- Limited capacity to filter sediment from flows
- Bio-Filter Bags and Fiber Rolls
Bio-filter bags are plastic mesh bags of various size filled with a variety of organic and in-organic materials designed to filter and detain flows and sediment. Fiber rolls are circular, dense, vegetated rubber tubes that act to detain sediments and runoff flows.
- To contain sediments onsite
- To slow surface water flow coming off a project
- Undisturbed Vegetated Buffers
Undisturbed buffers are swaths of preserved or established vegetation that act as perimeter controls for a project site. The rooted vegetation holds soils, acts as a wind break and filters runoff that might leave the site. Vegetation should be at least 1” in height and provide 80% ground coverage.
- Minimize soil movement off-site by wind or surface runoff
- May act as an alternate, or in certain cases, a supplemental measure to sediment barriers or sediment fence
- Storm Drain Inlet Protection
- Minimize sediment entering storm drain systems prior to permanent stabilization of disturbed areas
- Acts as a secondary perimeter, sediment control measure
- Inlet Inserts
Inlet inserts are a series of devices designed to trap and/or filter construction and stormwater flows leaving a site. Inserts can include bags, rocks, baskets and other materials that hang down into a catchbasin or inlet.
- Trap and/or filter sediment and other materials from site runoff and to prevent clogging of catchbasins and inlets