Erosion and Sediment Control Tip #43

 



There are a few changes to Alabama’s new Blue Book.  One change is the recommendation of a “standing pool” for a Sediment Basin.  This would be the water (minimum 1 foot) left in the bottom of the sediment basin pool when the skimmer can no longer skim the surface water. It is also sometimes called a sediment storage zone.  A standing pool can be achieved, either by setting your skimmer discharge pipe higher, or by creating an elevated platform for the skimmer to rest on.   By using the platform method , you can move the skimmer over and allow the basin to completely drain if needed.

 

Some may be concerned with a standing pool attracting mosquitos; however it has been found that sediment basins do not attract mosquitos as they do not like muddy water. Also, research has found that the standing pool of water helps to minimize resuspension of captured sediment when the next storm event causes runoff into the basin. 

 

Perry L Oakes, PE

Erosion and Sediment Control Program Coordinator

AL Soil and Water Conservation Committee

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