Exceedance Flow
Exceedance flow refers to surface water runoff that occurs when rainfall events exceed the design capacity of drainage systems, resulting in water following overland flow routes in accordance with site topography. Speak with a consultant about modelling exceedance routes for your development. The national SuDS standards require exceedance to be designed for in all new drainage schemes.
Case Example
During an extreme storm that exceeds the design capacity of a site’s drainage system, water is safely directed along roads and landscaped pathways (exceedance routes) away from buildings to prevent property flooding.
Design for extreme rainfall. Rida Reports models exceedance routes in your Flood Risk Assessment.