Two community groups want minimum flows set by the Otago Regional Council for the Waianakarua River and Trotters Creek investigated by the parliamentary commissioner for the environment, Dr Jan Wright.
They feel the summer minimum flows go against the expert and scientific advice provided to the council, are contrary to what the community wants, and put more emphasis on irrigation.
While the summer minimum flow of 200 litres a second for the Waianakarua River and 10 for Trotters Creek could have been appealed to the Environment Court, the two groups said they did not have the financial and volunteer resources to do so, nor to cover costs if those were awarded against them.
Initial recommendations were 20 litres a second for Trotters Creek and 270 for the Waianakarua River in summer.
Both the Coastal Otago River Communities and Waianakarua River Community Users groups were involved in consultation about the minimum flows and made submissions.
But they "are deeply concerned" at the minimums set, which "unnecessarily put the in-stream values of both watercourses at risk".
"In reaching its decision, the council has largely disregarded the result of community consultation, preferring instead to favour immediate economic interests by maximising access for irrigation abstraction at the risk of in-stream values," they told Dr Wright.
The final minimum flows chosen suggested a council priority was to avoid the need to restrict existing allocations, perhaps for fear of legal action.
The groups also worry the decisions will set the tone for other small rivers in Otago, placing the environment at risk.
Both the Waianakarua River and Trotters Creek were "rather unique" in coastal Otago because of the high quality of their water, their perennial flows, and high biological diversity.
That appeared to be due more to good luck than specific planning.
Local people told the council they wanted significantly higher minimum flows because they valued the in-stream qualities and did not want them put at risk.
The community put a premium on the recreational and environmental values, partly because of already degraded rivers in the area.
A healthy river had economic value for a community, because it attracted visitors and retained people in the area, the two groups said.
They have asked Dr Wright to consider six issues, including:
• Whether the minimum flows were consistent with the consultation process and evidence, and biased towards abstraction over in-stream values.
• There was evidence of bias, a contributing factor in the deterioration of many of the region's rivers.
• The council breached a direction of the Environment Court on using data from other catchments to set minimum flows.
• The capability of proposed monitoring to detect any decline in water quality and biodiversity so it could be corrected was questioned.
• Additional allocations could make it difficult to claw back water for a higher minimum flow.
