The Waiwera is a tributary of the Clutha River, located inland from Balclutha. There are currently four farmers taking water from the river for irrigation and stock water.
ORC policy planning and resource management director Fraser McRae said the plan change provided certainty for the community, which relied on the river for recreation, cultural, and agricultural uses.
"Minimum flows are used under the Resource Management Act to control the amount of water taken out of individual rivers," Mr McRae said.
"It's the level below which no more water can be taken to protect the values of the river. It also gives irrigators certainty about when and how much water they take within the parameters of their consent."
Plan Change 3C was publicly notified in December 2014 and submissions on the change were heard in April 2015. Six submitters had evidence presented to a hearing committee.
In August 2015, the hearing committee notified its decision on a minimum flow for the Waiwera of 300 l/s, with two appeals made to the Environment Court.
These appeals were resolved through mediation in December 2015, resulting in an agreed minimum flow of 280 l/s. There is a ‘recovery flow' provision, which means that if the river flow drops below 280 l/s because of consented water taking, the river's flow must return to 310 l/s before taking can recommence.
ORC chairman Stephen Woodhead said the end result was something everyone involved could be proud of, particularly the local community.
The plan change will become operative on March 1.
Those holding consents to take water will soon be contacted regarding when they will need to abide by the new minimum flow.
