The Rangitata Diversion Race or RDR is a combined irrigation and power generation scheme that diverts water from the Rangitata River to irrigate over 100,000hectares of farmland in Mid-Canterbury, 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 67km long, 10m wide and 3m deep.
