What is the maximum drainage area for an inlet protection device?

The maximum drainage area for an inlet protection device is indeed 1 acre. Inlet protection devices are designed to mitigate sediment and pollutant runoff from construction sites or disturbed areas before it can enter the drainage system. The limitation on the size of the drainage area is established to ensure that the device functions effectively.

When the drainage area exceeds this limit, the increased volume and velocity of runoff can overwhelm the capacity of the inlet protection device, leading to inadequate sediment capture and an elevated risk of runoff entering surface waters. Keeping the drainage area to 1 acre ensures a manageable volume of stormwater that can be effectively treated before it reaches the inlet.

This standard is grounded in best management practices for erosion and sediment control, which prioritize maintaining control over runoff to protect water quality. Larger areas would necessitate more extensive control measures to achieve the same level of efficacy, thereby complicating site management during construction activities.