Central Plains Water, or, more fully, the Central Plains Water Enhancement Scheme, is a large-scale proposal for water diversion, damming, reticulation and irrigation for the Central Plains of Canterbury, New Zealand. Construction started on the scheme in 2014.
The original proposal involved diversion of water, the construction of a storage dam, tunnels and a series of canals and water races to supply water for irrigation to an area of 60,000 hectares on the Canterbury Plains. Water will be taken from the Rakaia and Waimakariri Rivers.
In June 2010, resource consents for the scheme were approved in a revised form without the storage dam. From 2010 to 2012, the resource consents were under appeal to the Environment Court. In July 2012, the resource consents for the scheme were finalised by the Environment Court.
The Central Plains Water Enhancement Scheme originated as a feasibility study jointly initiated and funded by Christchurch City Council and Selwyn District Council.
The Central Plains Water Enhancement Scheme is contentious. It is opposed by community, recreation and environment groups, some city and regional councillors, and some corporate dairying interests. The scheme is supported by Christchurch City Council and Selwyn District Council staff and some councillors, irrigation interests, consultants, farming interests, and more recently, some corporate dairying interests.
Scope
Canterbury Regional Council has summarised the scope of the Central Plains Water enhancement scheme as follows; 'The applicants propose to irrigate 60,000 hectares of land between the Rakaia and Waimakariri Rivers from the Malvern foothills to State Highway One. Water will be abstracted at a rate of up to 40 m3/s from two points on the Waimakariri River and one point on the Rakaia River. The water will be irrigated directly from the river and via a storage system. The proposal includes a 55-metre high storage dam within the Waianiwaniwa Valley and associated land use applications for works within watercourses.' The proposed dam would be about 2 kilometres long, with a maximum height of 55 metres, with a base width of about 250 metres, and 10 m wide crest, with a capacity of 280 million cubic metres. The dam would be 1.5 kilometres north east of the town of Coalgate. The two rivers and the reservoir would be connected by a headrace canal, 53 kilometres long, 5 metres deep and 30 metres wide (40–50 metres including embankments). Water would be delivered to farmers via 460 kilometres of water races, ranging in width from 14 to 27 metres, including the embankments.
A brief history
In 1991, Christchurch City Council and the Selwyn District Council, in their annual planning process, agree on a feasibility study on irrigation of the Central Plains. The two councils provide a budget and set up a joint steering committee. In 2000, the steering committee contracts consulting firm URS New Zealand Limited to prepare a scoping report. In late 2001, the steering committee applies for resource consent to take 40 m3/s of water from the Rakaia River and the Waimakariri River. In January 2002, the steering committee releases the feasibility study and seeks to continue the project.
In 2003, the Central Plains Water Trust was set up to apply for resource consents, and the Trust establishes a company, Central Plains Water Limited, to raise funds from farmers via a share subscription. In 2004 Central Plains Water Limited issued a share prospectus and the share subscription is over-subscribed. In November 2005, further consent applications for land and water use were lodged with Canterbury Regional Council and Central Plains Water Limited becomes a 'requiring authority'. In June 2006, further consent applications for land use and a notice of requirement, the precursor to the use of the Public Works Act to compulsorily acquire land, are lodged with Selwyn District Council.
In July 2007, the trustees of Central Plains Water Trust informed Christchurch City Council that they had run out of money to fund the lawyers and consultants needed for the consent and notice of requirement hearings. Christchurch City Council gave approval for Central Plains Water Limited to borrow up to $4.8 million from corporate dairy farmer Dairy Holdings Limited. The hearing to decide the resource consent applications and submissions and the notice of requirement commenced on 25 February 2008.
In September 2012, Selwyn District Council approved a loan of $5 million to Central Plains Water Limited for the design stage.