D4RUNOFF NBS Library: https://d4runoff.eu/resources/

A sediment forebay is a post-construction practice consisting of an excavated pit, bermed area, or cast structure combined with a weir, designed to slow incoming stormwater runoff and facilitating the gravity separation of suspended solids. A sediment forebay is an essential component of most impoundment and infiltration NBS including retention, detention, extended-detention, constructed wetlands, and infiltration basins.