Difference Between Detention and Retention in Stormwater Solutions

Detention and retention may be used interchangeably in other fields, but not when it comes to implemented stormwater solutions. Each has its own distinction, and a faux pas it would be if a person were to mistakenly call one by the other’s name. Speaking in terms of stormwater BMPs (best management practices), the reason detention and retention are often interchanged is because both are methods of flood damage reduction. However, that’s where their similarities end. By definition, a detention stormwater BMP is an area where stormwater is temporarily stored, or detained, and is eventually allowed to drain slowly when water levels recede in the receiving channel.
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