Detention involves the capture, attenuation and controlled release of stormwater volumes before they discharge to receiving environments.
This moderates peak flows, reduces runoff velocities allowing contaminants to settle, and increases contact time between vegetation, soil and water. There are limitations to relying on detention as a singular practice in the catchment, including the loss of land, and the potential for super-position of peak flows (refer to the water quantity objectives in Section B).
Note: Technical design guide documents provide detailed advice for design and construction of devices.