Rangitata irrigation scheme at capacity

17:00, Sep 13 2014
Rangitata irrigation scheme at full capacity.
FULL AND FLOWING: With the scheme now fully operation, the Rangitata South Irrigation Scheme is supplying water to 16,000 hectares of land.

South Canterbury's massive Rangitata South Irrigation Scheme at Arundel is at capacity for the first time.

Resource consents were obtained in 2009, and construction began in January 2011.

Waimate businessman Gary Rooney, through his company Rooney Earthmoving, has designed, built and funded the massive scheme.

Rooney bankrolled the $115 million scheme, which is New Zealand's largest purpose-built irrigation storage facility.

His company had well over 100 staff working on the scheme and has shifted more than 5 million cubic metres of fill on the south bank of the Rangitata River.

The Arundel-based scheme will harvest floodwater from the Rangitata when flows exceed 110 cubic metres per second (cumecs), and it will store up to 16.5 million cubic metres of water in a series of seven storage ponds.


The scheme will be capable of delivering water to irrigate up to 16,000 hectares of land between the Rangitata and Orari rivers, currently involving 33 water users and their farms.

Rooney and his team have also collaborated with the Rangitata Diversion Race scheme to reach a reciprocal agreement which allows the two schemes to share their consented water and further increase the reliability of both schemes.

Water abstraction, filling and emptying of the storage ponds and water supply to the race network will be operated by a state-of-the art automated, wireless telemetry control system.

It includes 13 hydraulic gates, and around 80 kilometres of open races in four main legs.

Rooney was delighted to see the ponds at their capacity.

"It is fantastic for all who have put their hearts and souls into making this happen to finally be realising the vision and aspirations that began some 20 years ago and to finally provide this sort of opportunity to the community."

It involved the biggest earth-moving project in the South Island since the 1970s' Think Big power projects and is also larger than the Lake Opuha-based irrigation scheme.

It will also have a huge financial benefit for the farmers downstream, many of whom will have a reliable source of water for irrigation for the first time.

The Timaru Herald