Rangitata Diversion Race

The Rangitata Diversion Race or RDR is a combined irrigation and power generation scheme that diverts water from the Rangitata River to irrigate over 75,000 ha (190, 000 acres) of farmland in mid-Canterbury, in the South Island of New Zealand. The RDR project was the first major river diversion in New Zealand, and the largest irrigation scheme in the country. It was originally constructed by the Public Works Department between 1937 and 1944. The main canal is 67 km (42 mi) long, 10 m (33 ft) wide and 3 m (9.8 ft) deep. The RDR supplies three community irrigation schemes, two hydroelectric power stations, the Ashburton District Council stockwater race system and various private stockwater and irrigation schemes.

Canal data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).