The Rangitātā diversion race leads water from the Rangitātā River, across the head of the mid-Canterbury Plains, to the Rakaia River. This is the start of the race in the Rangitātā River. Water taken from this race irrigates 64,000 hectares of farmland. Water that is not taken from the race flows through a hydroelectric power station into the Rakaia River, and generates about 27 megawatts of electricity each year.