ABSTRACT
The vertical profile for a roadway follows the natural ground to have ups and downs. At a sag, the accumulated stormwater has to be diverted from the roadway system with a water quality control basin or stored in an adjacent open space to control peak-flow releases. Both water quality and quantity control basins are sized for the selected design event. The design volume for a roadway detention basin depends on the tributary area, catchment’s imperviousness, and rainfall duration which should be selected to maximize the volume difference between the inflow and outflow volumes.
