Dry detention ponds, also referred to as dry ponds, extended detention basins, or simply detention ponds, are designed to temporarily hold stormwater for a specified period, typically around 24 hours. This allows sediment and pollutants to settle, consequently reducing peak flow rates. Unlike wet ponds, dry detention ponds do not feature large permanent water pools; however, they may include small pools at the basin's inlet and outlet. While previously favored for flood control purposes, their effectiveness in providing water quality treatment is now recognized as limited.
Why use dry detention?
Dry detention basins are a popular choice for stormwater management because they offer a cost-effective way to control flooding. By capturing runoff and releasing it slowly, they reduce pressure on streams and channels downstream, preventing floods. Their simple construction and minimal land requirements make them a good fit for many development projects. However, they are not the best option for water quality improvement, as they primarily address water quantity. For a more complete stormwater management solution, dry detention basins are often combined with other practices designed to remove pollutants from runoff.
