What would indicate a problem with a silt fence barrier when assessing runoff?

What would indicate a problem with a silt fence barrier when assessing runoff?

• A. Runoff flows under, around, over, or between the fabric
• B. The fence blocks all runoff completely
• C. There is ponding behind the barrier with no seepage
• D. The fabric is clean and unbroken

Answer: (A)

The key idea is that a silt fence must form a continuous, well-anchored barrier to slow runoff and trap sediment. If you observe water flowing under, around, over, or between the fabric, it shows the barrier isn’t effectively intercepting the flow—there are gaps, an inadequate base trench, or loose/ damaged fabric allowing bypass. That bypass is the clearest sign of a problem and indicates the barrier needs repair or replacement (re-trench, reseal, re-stake, or replace fabric). Blocking all runoff would actually indicate it’s functioning, ponding behind the barrier can occur without necessarily signaling a failure, and a clean, unbroken fabric suggests the barrier is intact.

The key idea is that a silt fence must form a continuous, well-anchored barrier to slow runoff and trap sediment. If you observe water flowing under, around, over, or between the fabric, it shows the barrier isn’t effectively intercepting the flow—there are gaps, an inadequate base trench, or loose/ damaged fabric allowing bypass. That bypass is the clearest sign of a problem and indicates the barrier needs repair or replacement (re-trench, reseal, re-stake, or replace fabric).

Blocking all runoff would actually indicate it’s functioning, ponding behind the barrier can occur without necessarily signaling a failure, and a clean, unbroken fabric suggests the barrier is intact.