The Amuri Irrigation Company Limited (AIC) currently irrigates 22,175 hectares of land within the Waiau and Hurunui catchments. The original irrigation schemes (Waiau, Balmoral and Waiareka) all fall within the Amuri Basin and are operated by AIC.
The water take from the Waiau River is governed by minimum flow conditions in order to provide for instream values when the river is at low flow. The water taken from the Waiau River (for the Waiau and Waiareka schemes) is deemed to be highly reliable (99%), whereas the Hurunui River is only offers good reliability (95%). Reliability is measured as the amount of time during the irrigation season that water will be available averaged over the years of the record (this does not consider irrigation demand).
The irrigation season extends from early September to late April.
Currently AIC does not have any storage facilities but is considering storage opportunities as the Huruniu Waiau River Regional Plan has increased the minimum flows for the Hurunui and Waiau Rivers, which has significant implications for AIC reliability. AIC has reached agreement with the Zone Committee on delaying the implementation of the increased minimum flows in exchange for prioritising improved management of land and water delivered through our Environmental Management Strategy and Farm Environmental Plans. We have met these milestones and are hopeful that minimum flows will not be increased in the near future.
The AIC schemes are largely open channel as they were originally designed for border dyke irrigation; however the infrastructure does allow for continuous supply for spray irrigation.
In September 2016, AIC embarked on a project to pipe the majority of its open race system. This development will have significant benefits to AIC providing its shareholders with more efficient and pressurised delivery of water and allowing water which has been used as an operational buffer to irrigate further land, increasing the total irrigated area to 28,000 hectares.