The Mersey-Forth catchment is in the north-west of Tasmania. It uses water from four main rivers – Fisher, Mersey, Wilmot and Forth. Lakes high in the Western Tiers feed the rivers below and in turn the power stations.
The Mersey–Forth catchment is a run-of-river system, which means water flows to power stations directly from a river, and cascades through a series of power stations. This means the same water is used to generate energy multiple times.
Water from Lake Mackenzie flows through canals, tunnels and pipes to the Fisher Power Station. The water drops 650 metres to Fisher then runs into Lake Parangana.
Water needs to be released from Parangana Dam down the Mersey River for environmental reasons.