The Collie River catchment is a classic example of the deterioration of a surface water resource as a result of agriculture development.
The Collie Catchment is 150 km south of Perth with annual rainfall varying from 1100 mm in the west to 650 mm in the east.
Early this century it was realised that clearing of native vegetation for agriculture was causing increases in stream salinity in many areas of south-west Western Australia. During the post war agriculture expansion of the 1950s the effect of clearing on land salinisation was largely overlooked.
The catchment and reservoir management strategies applied to the Collie Catchment combined with engineering solutions was one of the first large scale attempts to control a major non source pollution problem in Australia.