Recent images of thousands of fish dying in an Otago stream and estuary are symptomatic of regional councils across the country failing to manage the environmental impacts of land-use on our waterways, Fish & Game New Zealand say.

"This environmental tragedy wasn’t an isolated incident, and it isn’t limited to my home patch, Otago," New Zealand Fish and Game Council Chair Ray Grubb says.

"Across the country, many are of these important ecosystems are close to ‘flipping’ - reaching a point where they are so polluted that they can no longer sustain life - as we saw in the Kaikorai stream over the weekend."

Mr Grubb levels much of the blame for this growing environmental disaster at regional councils.

"Regional councils are supposed to be responsible for sustainably managing natural resources and implementing the rules around water quality and quantity. In many cases the rules are inadequate, but even when they are sufficient regional councils fail to enforce them, instead focusing more on regional development and economic growth, and ignoring the environmental costs."

Estuaries are often regarded as the lungs of the natural water system in New Zealand: vitally essential ecosystems that support a large diversity of species and are breeding and feeding grounds for fish and birdlife. However, they are also where the results of upstream activity accumulate and are most pronounced.

Several estuaries have already ‘flipped’ and these cannot be expected to recover from a state where nothing can survive. An example is the New River estuary in Southland, where eutrophic conditions have now expanded to 400 hectares.

Mr Grubb says it is "galling" that the Kaikorai disaster was quite likely a result of Otago Regional Council’s (ORC) own actions.

"The opening of the stream mouth resulted in an overheated and anoxic environment which looks to have caused the demise of thousands of indigenous fish and sports fish.

"The situation is compounded by the fact regional and local councils have generally treated urban streams as little more than drains for over a hundred years."

Across the country, regional councils are failing New Zealanders. In November, Greater Wellington Regional Council had to prosecute itself after it flushed the lake at Birchville dam, with the heavy sediment flowing downstream leaving dead trout smothered in mud.

"New Zealanders will be best served by clear policy which protects our estuaries and waterways for future generations and provides for proper enforcement by regional councils, as is their job."

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