Silt Fence Placement
Placement refers to where and in what shape silt fence is placed on site. Remember, silt fence must pond and filter water! No matter how well it is installed, if water runs around the end(s), the silt fence is worthless. It must be placed where it will store water, with the ends higher than the some interior point - often times a ‘smile’ or J-hook shape is required to create a storage area. Long runs should be avoided, and broken up into smaller segments.
On-site adjustment to the Storm Water Pollution Prevention Plan (SWPPP) is mandatory for an effective silt fence as slopes, etc. can’t be anticipated on a desktop and designs may have to change to fit the site. A good contractor should have someone on the crew knowledgeable about sediment control to decide the proper placement of silt fence. The first goal is creating a storage area for runoff and filtration, the second is storing the greatest quantity of water without large overflows.
Sometimes it is better to say ‘this is not a proper place for silt fence, XYZ is a better option’. Or, ‘silt fence won’t be effective here, we need to move it somewhere else’. Placing silt fence on contours sounds good on paper, but it is very difficult in the field. Installing multiple smiles where you can plan for runoff accumulation and filtration is a better plan.