Environment Canterbury's decision to allow lower flows in the Waitaki River tips the balance between business interests and the health of the river in favour of industry, a conservation group says.
Last month, the regional council (ECan) adopted recommendations on the Waitaki Catchment Water Allocation Plan's Plan Change 3 and, yesterday, the appeal period on the decision closed.
The plan increases the maximum amount of water hydro generator Meridian Energy and hundreds of farmers on irrigation schemes in the Waitaki Valley can take.
ECan commissioner Prof Peter Skelton said the independent hearing panel decided the economic benefits of providing for "high reliability of supply'' would be between $2.8million a year and $6.9million a year, which they considered to be a "considerable economic benefit''.
Lower Waitaki River Management Society chairman Ian McIlraith said the ECan decision, which lowered the minimum flow at the Waitaki River mouth below the 150cumecs set in 2006, was "frustrating'' and the "democratic process has been undermined''.
The society said ECan's decision ran counter to 80% of 550 public submissions.
"This concerning change to the plan opens the way for more frequent lower flows in the river leading to problems like more didymo issues and algal proliferation.''
Mr McIlraith said lower flows would affect birds, fish and water temperature and would cause problems for recreational users.
From "day one'' the society had focused on holding the minimum flow, Mr McIlraith said.
When ECan issued consents under the 2006 plan it did not allow for the renewal of historic consents.
Those consent-holders had now been accommodated with Plan Change 3 without proper regard for the health of the river, Mr McIlraith said.
On Thursday, Prof Skelton stood by the decision made by the panel of commissioners, chaired by former Environment Court judge Gordon Whiting.
He dismissed the society's concerns the process had been undemocratic.
ECan was satisfied "the statutory requirements have been met'', he said.
"And [he was satisfied] that the independent hearing commissioners ... followed an inclusive process that gave everyone, and every issue, a fair hearing.''