Irrigation NZ is pleased to announce a seasonal water allocation method is all go for Canterbury.
Environment Canterbury has approved IRRICALC as an accepted method for determining seasonal irrigation allocation requirements.
Irrigation NZ (INZ), working in partnership with the combined Canterbury Provinces of Federated Farmers, contracted Aqualinc Research Ltd in 2008 to develop a "seasonal irrigation allocation methodology" that took into account all the key drivers of irrigation – soil, climate and irrigation systems and their management that would allow irrigators to accurately calculate their water allocation needs for irrigation consents with confidence.
INZ chief executive Andrew Curtis said the INZ initiated project had been prompted by calls from irrigators for an alternative to the proposed seasonal water allocation methodology contained in Environment Canterbury’s Proposed Natural Resources Regional Plan (NRRP).
"What we have done is come up with an alternative approach which farmers can use if they wish," Curtis said.
"It is important to get water allocations right. Farmers must invest a great deal of money to install irrigation, a requirement of the market place that refuses to accept non-delivery of food merely because of a drought. Farmers, and the market, need confidence that the volume of water they are allocated will be sufficient. The financial consequences of drought loss are severe, and not just to farmers."
INZ supports the introduction of seasonal volumes that in conjunction with water metering will allow the water resource to be better managed.
"Thereby optimising the economic potential of the water resource while ensuring we protect the environment. It’s about sustainably managing our resources for future generations."
The Irricalc methodology is based on internationally accepted best practice – soil-water balance model as outlined in United Nations Food and Agriculture Organisation guidelines, which has then been refined using Canterbury monitoring data.
The Irricalc programme is a simple, fast, precise water management tool that assists in calculating irrigation water schedules, estimated annual water usage, maximum applied water allowance and the average demand for the peak season.
INZ and Environment Canterbury have agreed on a set of criteria against which to test any water allocation methodology. The Irricalc methodology meets these criteria and is seen as a robust approach for the Canterbury situation.
"One of the problems that we have at the moment is that there is presently a lack of comprehensive crop water use data in New Zealand which results in much theoretical dispute and uncertainty. But it is reassuring to see Environment Canterbury, along with a number of other regional councils, is being proactive in this space," Curtis said.
Environment Canterbury is installing lysimeters and weather stations on a number of farms over the next few years in order to gather a much better handle on the actual situation that will enhance the ability to refine the methodology over time.
The Irricalc methodology and accompanying maps for determining 80% efficient irrigator four in five year reliability, consistent with current Environment Canterbury policy, are available on the Irrigation NZ website www.irrigationnz.co.nz/publications/irricalc/, 80% efficient irrigator nine in ten year reliability maps are also available.
It has been designed to be easy to use especially if you follow the how to guide. INZ will be working with ECan to turn this methodology into a calculator in the future.
Further comment:
Andrew Curtis – INZ Chief Executive
03 379 3820 or 0274 966314