Why is a hardened bottom beneficial in a sediment forebay?

A hardened bottom in a sediment forebay is beneficial primarily because it aids in sediment cleanout. This design feature allows for more efficient removal of accumulated sediment over time. A hardened surface can withstand the forces of sediment moving and settling without being eroded or disturbed itself, thus making it easier for maintenance crews to access and clean the area.

In contrast, a softer or natural bottom might trap sediments and complicate the cleanout process, leading to increased maintenance challenges and potentially reducing the effectiveness of the forebay. The stability provided by a hardened bottom supports ongoing management efforts to maintain optimal functionality in the stormwater management system.

While a hardened bottom may have some advantages in terms of preventing weed growth and providing stability to surrounding structures, its primary purpose is to facilitate easier sediment removal, ultimately ensuring the forebay operates effectively in filtering and managing stormwater runoff.