To be leaders in Water Management providing Reliable, Economic and Sustainable Supply
Waimakariri Irrigation Limited currently hold fourteen resource consents granted by Environment Canterbury and two resource consents granted by Waimakariri District Council. These relate to the abstraction, use and discharge of water and the construction of structures to transfer the water.
Consents from Environment Canterbury deal with water and the construction of structures in river beds. Consents from the Waimakariri District Council deal with the construction of structures outside of the river beds. Minor structures are also authorised by the Waimakariri District Plan.
The fundamental consent for the operation of the scheme is consent CRC000585* which allows the take and use of up to 10.5 m3/s of water from the Waimakariri River from the two scheme intakes at Browns Rock – This consent was updated on the 8 March 2007 to become CRC000585.5 allowing 10.5 m3/s to be applied to the existing irrigated area of 18000 ha but under a new management plan. The new management plan will involve WIL irrigators auditing their on farm irrigation systems to help maximise efficient use of water on their farms. The move to ensure further efficiencies of on farm systems has resulted from WIL and ECAN both seeking to ensure efficiencies (where possible) and responsible use of water. More information on this initiative will be published when finalized. The Conditions attached toboth existing and new consents restrict the availability of this water at times of low flow in the Waimakariri River.
The release of water into the Eyre River is authorised by the consent CRC952571 which allows a by-wash discharge of 0.5 m3/s and a higher discharge of up to 3 m3/s between the months of August to May when groundwater levels are low. This higher discharge flow is made up of the 1.5 m3/s allocated for the Eyre River and 1.5 m3/s of irrigation water during times when irrigation is not at its peak demand.
The construction of the new intake for the scheme has been authorised by consent CRC952568. To maintain the flow of river water to the intake, there are times when machinery must enter the Waimakariri River channel. This work is authorised by consents CRC952566 and CRC952567.
The construction of the scheme’s settling ponds and main distribution races across the Waimakariri-Ashley Plain has been authorised by the Waimakariri District Council consents RC950293 and RC005210. Where these races cross rivers, they are covered by Environment Canterbury Consents CRC000955, CRC001015, CRC952577, CRC952578 and CRC010487.
In the original scheme consent applications to the Regional Council it was proposed that water would be discharged to the Ashley and Cust Rivers to enhance these waterways at times of low flow. The application to discharge this water was not granted, however the construction of the structures that would be needed for the discharge was approved in consents CRC952572, CRC952573 and CRC952575.
Also, in the initial scheme proposal it was envisaged that the settling ponds at the intake would be cleaned by flushing sediment back to the Waimakariri River. This has been authorised by consent CRC952570, however the conditions on the consent are so difficult to meet that it is not proposed to utilise this consent at the present time. Instead, the ponds will be cleared by mechanical excavators.
The main ongoing consents for the scheme expire in 2031. Those which have been granted for shorter time periods relate to construction activities that have already been completed. However, all the consents granted by Environment Canterbury contain a condition that allows them to review the consent conditions on an annual basis – to deal with any adverse environmental effects that may be occurring or to comply with the requirements of a regional plan.