Arguments almost a decade old could erupt again over proposed major changes to water allocation and minimum flows in the lower Waitaki River.
The Waitaki catchment water allocation regional plan was prepared in 2005 by the Government-appointed Waitaki Catchment Water Allocation Board, which considered about 1200 submissions and listened to 334 witnesses at 122 hours of sometimes bitter hearings in Oamaru and Omarama.
Two more minor changes have already been made - plan change 1 making extra water available from Lake Pukaki when there is a major electricity crisis and plan change 2 with farmers giving up some irrigation from the Maerewhenua River, to improve its flows, for a supply from the Waitaki River.
Now, Environment Canterbury (responsible for the plan) is calling for public submissions on plan change 3, the most controversial so far because it goes to the heart of the water allocation and minimum flow for the Waitaki River.
Already, it has been criticised by some parties involved in the 2005 process.
Submissions opened on Saturday and close with Environment Canterbury (ECan) by 5pm on August 22.
They will then be heard and considered, most likely in Oamaru, at a date yet to be set.
The plan change was prepared in conjunction with the Lower Waitaki-South Coastal Canterbury Zone Committee, a community committee which consulted stakeholders on the river, including Meridian Energy Ltd, Ngai Tahu and irrigators.
The change aims to. -Address uncertainty in the plan about security of supply for irrigation when consents are reviewed or renewed.
Provide greater certainty for Meridian's replacement generation consents.
Enhance mahinga kai (Maori food) sources.
Make minor amendments so the plan is easier to implement.
The most controversial issue will surround changes to the minimum flows in the lower Waitaki River.
The 2005 plan provided for a minimum flow of 150 cumecs but also for Meridian Energy to release from the Waitaki dam extra flows of between 10 and 80 cumecs, depending on the time of year.
However, those extra flows could not be introduced until Meridian's resource consents for the Waitaki dam came up for renewal in 2025, because its existing consents set flows less than those specified in the plan.
Now Meridian has agreed, as part of the plan change, to introduce that earlier if other changes are made to the plan.
That would include lowering the minimum flow to between 102 and 144 cumecs, depending on the time of year.
Another change is to clarify the position of resource consents to use water that were approved before the plan was prepared.
These consents have minimum flows, when water cannot be taken, ranging from none to 130 cumecs.
The plan change would bring them all up to 102 cumecs, or the flow specified on the consent, whichever was higher.
There is the issue of under-allocation of water between Black Point and the Waitaki Dam and confusion over the amount of water from mining rights.
The plan change also sets aside water for projects such as restoring flows of the Wainono Lagoon (east of Waimate) through the proposed Hunter Downs irrigation scheme to enhance traditional food sources.
Details of plan change 3 and how to make submissions can be found on www.ecan.govt.nz/wcwarp3
