Water Shortage Direction for Lake Opuha

Water Shortage Direction for Lake Opuha

Environment Canterbury will this weekend notify a Water Shortage Direction for the Opihi River, South Canterbury, and its tributaries. The Temuka River and its tributaries are not part of the Direction.

The Direction is in response to unusually low water levels in Lake Opuha for the time of year, the lowest since 2001. The lake stores water which is used to augment Opihi River flows as outlined in the Opihi River Regional Plan. It also supplies water to shareholders of Opuha Water Ltd by releasing water to the Opihi River to offset irrigation takes. It also supplies community and private domestic water supplies and produces electricity.

The Opihi Plan puts water take restrictions in place once the lake level drops to 375 metres above mean sea level. The Water Shortage Direction will bring those restrictions in sooner, beginning at 386 metres above mean sea level. On October 14, the level was 385.6 metres. Based on the current lake level, the restrictions outline in the Water Shortage Direction will be effective immediately.

The Direction, over the next 14 days, will affect three key areas:
• Opuha Water Ltd will be required to maintain a minimum flow in the Opihi River of six cumecs, as opposed to 8.5 cumecs.
• Irrigators with shares in Opuha Water Ltd will only be allowed to take 75% of their normal daily volume.
• Community or private drinking water supply consent holders will only be able to take 87.5% of their normal daily volume.

The Water Shortage Direction applies for 14 days at a time. If no rain replenishes the river and lake system in coming days, Environment Canterbury is able to renew it every 14 days if necessary. If significant rainfall occurs, the Direction may be cancelled early.

The recommendation to put a Direction in place came from the Opuha Environmental Flow Release Advisory Group, which is responsible for modifying the environmental release flows within the provisions of the Opihi River Regional Plan The group is comprised of a representative of the Opuha Dam Partnership; one instream representative (appointed jointly by the Department of Conservation and the Central South Island Fish and Game Council);one Takata Whenua representative; one representative of irrigators (appointed by South Canterbury Federated Farmers); and one representative of the Timaru and MacKenzie District Councils. The chair of the advisory flows group is Judy Blakemore, Utility Operations Engineer for Timaru District Council.

“A number of meetings have been held to date to agree upon the water shortage direction,” said Environment Canterbury Director Resource Management Kim Drummond. “This has been a collaborative effort with the members of the advisory group and council staff aiming to protect the many values and uses made of this body of water.”

ENDS