The Roxburgh Dam is the earliest of the large hydroelectric projects in the lower half of the South Island of New Zealand. It lies across the Clutha River / Mata-Au, some from Dunedin, some to the north of the town of Roxburgh. The settlement of Lake Roxburgh Village is close to the western edge of the dam. History Development In 1944 the State Hydro Department estimated that even with the power stations currently under construction they would only be able to meet projected South Island load up until 1950 or 1951 and that a new large power station was required. Detailed investigations by the Public Works Department identified two alternatives, Black Jack's Point on the Waitaki River (where eventually Benmore Power Station would be built) and Roxburgh Gorge on the Clutha River. A power station at Roxburgh had the advantage of being less remote, requiring less geological investigation, half the materials for the same power output and a better climate in which to undertake construction work, which were important considerations at a time of serious shortages of labour and cement Historical records showed that the long term flow of the river was and that a controlled flow of would be possible through the power station. The designers estimated that with an overall efficiency of 85% the mean output would be 160 MW and assuming an annual power factor of 50% the station could deliver a maximum output of 320 MW. The Clutha River is fed from Lake Hāwea, Lake Wakatipu, and Lake Wānaka. There were already existing control gates on the Kawarau River at the outlet of Lake Wakatipu and it was decided to control the flows from the remaining lakes. After investigation found that the soil conditions were unsuitable at Lake Wanaka only Lake Hāwea received new control structure. This was commissioned in 1958 and consists of four radial gates housed in an earth dam. The dam raised the existing lake level and currently provides approximately 290 GWh of storage. In December 1947 the Labour Government approved plans to build a hydro power station on the Clutha River. Initially only three 40 MW generating units were to be installed with the station having an ultimate planned capacity of 320 MW. The Clutha River between Alexandra and Roxburgh runs through a deep gorge which offered a number of locations for a power station. Investigations identified five alternative schemes at the