The purpose of this bulletin is to advise on the WAPC current policy and practice regarding urban stormwater management and considerations the WAPC will take into account when dealing with urban stormwater management for new residential subdivisions.

Urban stormwater is the run-off from urban areas. Various factors influence the quantity and quality of stormwater. These include the duration and intensity of rainfall, soil type, proportion of impervious surfaces, contours of the land, land use, and the design and management of stormwater systems. Stormwater is also a source of contamination. In addition to contaminants from the atmosphere, stormwater has the potential to transport accumulated surface material including litter, dust, oils, grease, fertilisers and other nutrients into waterways.