Dams Construction
The Opuha Dam is situated at the confluence of the North and South Opuha Rivers 17 kms north-east of Fairlie in New Zealand. The dam is an infrastructure project undertaken by the community of South Canterbury. The actual project itself consists of a 50 metre high earth dam, with a single hydro turbine and a lake covering up to 710 hectares and storing over 74 million cubic metres of water.
The lake provides water to maintain environmental flows in the downstream catchment and for irrigation as well as urban and industrial supplies. Renewable hydro electricity is generated with all the water released from the dam.
Water storage is prioritised for release into the Opuha River which flows into Opihi River to ensure minimum flows are maintained at all times and especially in times of drought and/or low natural flows.
Initially, the concept came out of discussions between the Electricity Corporation of New Zealand (ECNZ) and the Opihi Augmentation Society, and resulted in the Opuha Dam Partnership being formed back in 1992 to commercialise the project. At this time, it enjoyed the support of local Lines Company, Alpine Energy Ltd, Timaru and MacKenzie District Councils, the Opihi River Development Company and two irrigation companies – Levels Plain Irrigation Company Ltd (which existed prior to the dam) and South Canterbury Farmers Irrigation Society (SCFIS) which was established to represent the farmers who would in future be able to access water from the dam.
Water storage is prioritised for release into the Opuha River which flows into Opihi River to ensure minimum flows are maintained at all times and especially in times of drought and/or low natural flows.
Initially, the concept came out of discussions between the Electricity Corporation of New Zealand (ECNZ) and the Opihi Augmentation Society, and resulted in the Opuha Dam Partnership being formed back in 1992 to commercialise the project. At this time, it enjoyed the support of local Lines Company, Alpine Energy Ltd, Timaru and MacKenzie District Councils, the Opihi River Development Company and two irrigation companies – Levels Plain Irrigation Company Ltd (which existed prior to the dam) and South Canterbury Farmers Irrigation Society (SCFIS) which was established to represent the farmers who would in future be able to access water from the dam.
Construction of the dam began in 1995 and progressed very successfully until Waitangi Day 1997 when three days of solid rain in the upper catchment resulted in the partially completed dam being overwhelmed and breached by the high inflows. While there was extensive damage downstream and to the construction site, the project faced only a temporary set back. Repairs were swiftly completed and the project was commissioned and officially opened in November 1998. More details
