The Avon River Basin covers 122,000 square kilometres and supports 50,000 people in rural communities. The Swan River catchment covers 2,000 square kilometres and supports much of Perth's urban population of nearly 1.4 million people. The river system linking this huge Swan-Avon Catchment drains to the Swan River Estuary which receives water from both the Avon Catchment and the Swan Catchment . The Avon River Basin is located in the South West of Western Australia. The basin has a Mediterranean climate.
Rainfall diminishes from west to east.
Geomorphology also changes from a dissected landscape in the west to one of subdued drainage gradients in the east. These factors influence production systems, population development patterns and the degradation hazard to land, water and natural systems. Annual streamflow discharging into the Swan estuary. Yilgarn Catchment - irregular streamflow events that discharge via the Avon River water into the Swan estuary. Lockhart Catchment - irregular streamflow events that discharge via the Avon River water into the Swan estuary.