On Thursday October 8th, 24 members of the Natural History group went on a trip to the Mid Canterbury Irrigation.
We were accompanied by Hamish Tait, the General Manager of Mayfield Hinds Irrigation Ltd, who was ably assisted by two of our members – Terry Heiler and Alan Stevens. A comprehensive viewing of many parts of the scheme;- the intake from the Rangitata River, (including the trout diversion race), border dykes, the very large Carew storage ponds (I will never know how they laid the liners in Canterbury winds), the farmers’ turbines, and smaller power schemes generating electricity to help run pumps on farms, the technology which automatically regulates the canal flows by remote adjustment, and the number of large pivot irrigators, the increase in soil depth on the lighter Lismore Gravels, due to increased grass root growth, and so much more.
Some key facts of the Mayfield Hinds Irrigation Scheme
- Delivers up to 16.8 cumecs from the Rangitira Diversion race (RDR)
- It is the largest privately-owned scheme in NZ serving 36,000 hectares
- The RDR is a 67km canal delivering water to 4 irrigation schemes with hydro-generation at Montalto and Highbank. Three of the schemes are:
- Mayfield/Hinds scheme between the Rangitata and Hinds rivers
- Valetta scheme between the Hinds and Ashurton rivers
- Ashburton/Lyndhurst scheme between the Ashburton and Raikaia rivers
- First water was delivered to the scheme in 1947
- The scheme was purchased from the government in 1990 and is now a co-operative company
- Today 90% of the land is spray irrigated and variable flows are delivered to on-farm ponds
- 3.5mm/day allocation is subject to river restrictions in the season 10 September to 9 May
- 320km of open channels with a fall of 300m across the scheme
- The scheme is continuing to modernise with telemetry and automation
- There are 140 farm ponds averaging 40,000 m3 capacity.