Mangahao Site

The Mangahao station was officially opened on the 3rd of November 1924 by the then Prime Minister Bill Massey. King Country Energy, in conjunction with Todd Energy, acquired this generation plant in 1997.

The water stored in the reservoirs formed by the two dams on the Mangahao river is brought by a 1.6km long tunnel to the third reservoir on the Tokomaru stream and then to the surge chamber by a 2.1km tunnel.

The headwaters of the Mangahao River are a major tributary of the Manawatu River. The total catchment area of the scheme is 86 square kilometers in an area of high annual rainfall, which on average exceeds 3,700 millimeters.

Station statics

Location: East Road, Shannon
Average Annual Output: 126 GWh
Total MW rating: 38 MW
Head: 271 meters
Turbines: 1 x Horizontal Francis, 2 x Pelton Wheel, all synchronous
Generators: 1 machine of 28.9MW, 2 machines of 6MW