Happy Valley Reservoir - Continuing Use

Continuing Use

Initially 15 kilometres from Adelaide, the reservoir is now largely enveloped by the city's southern suburbs, of which the relocated Happy Valley village is now one. Although the reservoir is relatively small in capacity; holding only 11,500 megalitres and is dwarfed by Mount Bold Reservoir which is at least four times larger, it is the site of the biggest water treatment plant in Adelaide and is responsible for providing more than 40% of the city's water.

With public access prohibited, the natural bush of the reservoir's enclosed catchments are home to kangaroos, echidnas and koalas. Several areas have also been planted with managed pine plantations to reduce soil erosion and provide an income from harvesting. As a result of the plantations being located within what are now inner city suburbs they have become almost iconic. In the early 2000s, plans to harvest the mature pines were blocked following public protests over the visual impact the clearance and replanting would have on the surrounding suburbs.

Water from the dam was originally supplied to Adelaide through a tunnel under Black Road. In the early 1960s, the original intake tunnel from the Clarendon Weir was increased in size to allow access by maintenance vehicles, and a second outlet tunnel was constructed under South Road. In 1986 this new tunnel became the sole outlet for the reservoir when the original outlet was abandoned. At the same time the Thorndon Park Reservoir was decommissioned and reestablished as a recreational park.