Hydroelectric power station, New Zealand

South Island has a rugged landscape dominated by New Zealand’s Southern Alps, whose highest point is 12,320 ft (3,755 m) and from which countless rivers flow. Many of these like the Ohau River were made partially artificial to fill the country’s energy needs. The Ohau A hydroelectric project built on the upper part of the Waitaki River is a massive complex of dams and canals. Its construction was begun in 1971 and required the excavation of 70 million ft3 (1,983,000 m3) of rock from the banks of the Ohau River, then of 17 million ft3 (481,390 m3) to build the discharge pipes. Hydroelectric power plants and their huge dams were long in favor because of their use of a renewable resource and generation of relatively little pollution, but we have come to realize that they exert tremendous pressure on the ecosystem. Consequently, in this country proud of its ecotourism and whose economy partially depends on tourism, emphasis is now placed on finding solutions ever-more respectful of the environment, such as the use of wind power.