The Waiau River was once the mighty river of Southland, possessing strength in both volume and power.
The demand for hydroelectricity generation meant the main source of the Waiau watershed was directed through a tunnel at the western end of Lake Manapouri. The water is now released into the sea at Deep Cove on the Fiordland Coast.
This has resulted in the decrease of the river’s water flow so the formerly mighty river is now significantly reduced. There is still fishing stock in the river and the Waiau River’s trout population attracts fishermen to the region throughout the year.