SWPPP (Stormwater Pollution Prevention Plan)

A Stormwater Pollution Prevention Plan (SWPPP) is a site-specific document required under most NPDES construction stormwater permits. It identifies a project's pollution sources and lists the Best Management Practices (BMPs) — erosion control, sediment control, and good housekeeping measures like concrete washout containment — the site will use to keep pollutants out of stormwater.

SWPPPs are typically inspected on a recurring schedule (often weekly and after significant rain events), and an uncontained washout area is one of the most common findings cited during those inspections.