A catchment is an area of land that collects surface water.
Salisbury is predominantly a suburban area comprising a mix of urban land-uses including residential, commercial and industrial zones. In general, urban areas are confined to east of Port Wakefield Road (except for St Kilda and Globe Derby), with non-urban areas located west of Port Wakefield Road.
There are four main catchments within Salisbury. Stormwater is collected from the roads into a network of pits and pipes in these catchments before draining by gravity into three main watercourses:
- Helps Road Drain
- Little Para River
- Dry Creek River
Topography of the catchment is dominated by the foothills of the Para Escarpment to the east, which contrast the low relief areas to the west towards the coast.
Stormwater harvesting systems are designed on a ‘whole of catchment', integrated approach. An understanding of the nature and function at a sub-catchment level is required. A catchment approach to recycling stormwater includes an awareness of:
- development and changing land uses within a catchment
- water quality risks
- flood control measures
- catchment maintenance activities
- abilities to control and divert flows within sub-catchments