The Nerang River catchment is the largest and most significant river system on the Gold Coast. Its upper reaches in the McPherson Range and Springbrook Plateau deliver flows through significant rural areas and also feed into the Hinze Dam, creating Advancetown Lake, the Gold Coast's main water supply, and Little Nerang Dam. These two reservoirs provide a large percentage of potable water for the Gold Coast and are managed by Gold Coast Water. The Hinze Dam has had a significant flood mitigation effect. In the river's lower catchment, multi-branched canal developments and a number of artificial tidal and freshwater lake systems have influenced and altered large aras of the floodplain. These canal developments provide a range of opportunities for many residents including boating and recreational fishing. The canals and lakes provide habitat to a range of aquatic, terrestrial and marine flora and fauna. The canal systems provide for drainage of stormwater and contribute to flood mitigation, but can periodically be subject to contamination via stormwater drainage.