The Clarendon Weir is a concrete gravity weir across the Onkaparinga River, located in the suburb of , approximately south of the Adelaide city centre, in South Australia.
Overview Built in 1894–96 as a solution to Adelaide's sewer problems, the weir supplied water to the Adelaide plains to flush the sewers as there simply was not enough water to keep the population healthy. A tunnel was built with ponies and carts through the hills to Happy Valley where a reservoir was built. The water flowed by gravity from the Weir through the tunnel to Happy Valley Reservoir. There is no other catchment for this reservoir. Mt Bold Reservoir was added in the 1940s to again supplement Adelaide's water supply with the Clarendon Weir acting as a holding dam down stream. The water is used to supply about half of the Adelaide region's water needs.
The weir wall is high and long. When full, the reservoir has capacity of and covers , drawn from a catchment area of . The uncontrolled spillway has a flow capacity of .
In the mid-1960s, the wall of the Clarendon Weir, originally constructed with large blocks of Macclesfield marble, was raised from to its current height of .
The weir was listed on the former Register of the National Estate, and was added to the South Australian Heritage Register on 8 November 1984.
See also
List of reservoirs and dams in South Australia
References
External links