Massive irrigation plans threaten the fragile Mackenzie Basin and could transform parched high-country land into a replica of the Canterbury Plains, conservation groups say.
Consent applications from 36 companies could lead to an extra 90 million cubic metres of water a year being taken for irrigation mostly on Crown land. More than 27,000ha is set for irrigation.
If granted, the Upper Waitaki catchment's annual water allocation for agriculture and horticulture would come within half a million litres of its maximum of 275 million cu m.
An independent hearings panel will hear evidence over 10 weeks from September regarding 126 applications for irrigation consents in the Upper Waitaki catchment, including some consent renewals.
Farmers, some of whom are pastoral lessees, argue the water would provide a lifeline, transforming arid land into productive pasture and cropping land.
The Department of Conservation opposes the irrigation plans, some of which might clash with its proposal for a 30,000ha Mackenzie Basin Drylands Park.
Forest & Bird South Island conservation manager Chris Todd called it a "water grab" and demanded the Government step in.
"It's impossible to intensify farming in the Mackenzie Basin without ... polluting the lakes and without destroying the indigenous ecosystems," he said.
"The plants, insects and lizards are specifically adapted to living in this environment, and it's an environment that's very special to New Zealanders.
"It's the gateway for tourism to the high country ... [it] will become, essentially, another Canterbury Plains."
The Mackenzie Basin was home to 56 threatened plant species, he said.
Dunedin businessman Murray Valentine, who has an interest in many South Island farming, tourism and hotel companies, said some of the Mackenzie Basin was close to desert.
Valentine, a director of Mackenzie Irrigation Co, owns Simons Pass Station, which wants to irrigate 4800ha near Lake Pukaki.
"There's very little tussock left and, if you leave it in its present state, the chances are that it will all blow away," he said.
"We don't think there's a choice to leave it as it is."
Without irrigation, wilding pines would take over.
Irrigated land would probably be used to graze sheep and beef cattle, he said.
Forest & Bird is calling for conservative grazing and better rabbit control on the land, so native vegetation can recover.
Department of Conservation Twizel area manager Rob Young said there were concerns over water quantity and quality and the effect of irrigation on ecosystems and native species.
In a report on environmental stewardship and tenure review released last month, Parliamentary Commissioner for the Environment Jan Wright said the proposed drylands park would contribute to the range of ecologies in the high-country conservation park network.
The report said high-country tourism contributed considerably more to the national economy than high-country sheep farming.
However, Wright said there was little value in protecting any more high-country tussock grassland..
It was wrong to assume that land that was of marginal use for farming must instead have conservation values, she said.
In 2006, Meridian Energy and Mackenzie Irrigation Co agreed on a capped volume of water being reserved for irrigation use within the Upper Waitaki catchment.
"Whether or not the irrigation actually proceeds depends on whether the irrigation consent applicants obtain resource consent or not," Meridian spokeswoman Claire Shaw said.
- © Fairfax NZ News
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