Question

1. describe two best management practices (bmps) used at construction sites to reduce stormwater pollution.

source: https://www.epa.gov/npdes/stormwater-discharges-construction-activities
student response:

Explanation:

1. Erosion Control Blankets: These are biodegradable or synthetic mats (like straw, coconut fiber, or plastic netting) placed over exposed soil on construction sites. They protect the soil from being eroded by rain, reducing the amount of sediment that enters stormwater. The matting slows down water flow, allows water to infiltrate, and holds soil particles in place, preventing sediment-laden runoff.
2. Sediment Basins: These are constructed depressions (usually with a dam or weir) that collect stormwater runoff from the construction site. As water enters the basin, sediment (dirt, sand, etc.) settles out because the water's velocity decreases. This prevents the sediment from reaching nearby water bodies, reducing pollution.

Answer:

1. Erosion Control Blankets: These mats (biodegradable/synthetic) cover exposed soil, slowing water flow, promoting infiltration, and holding soil to reduce sediment - laden stormwater runoff.
2. Sediment Basins: Constructed depressions collect stormwater, and as water velocity decreases, sediment settles out, preventing it from polluting nearby water bodies.