Professor Mike Joy has welcomed the Green Party's plan to make all of New Zealand's rivers and lakes safe to swim in.
The party announced the move yesterday, calling it its No 1 environmental policy for the election campaign.
Joy, a freshwater ecologist at Massey University, called the approach "really sensible".
"I like the sound of it," he said. "They've obviously thought long and hard about it."
Joy has long been outspoken about the state of New Zealand's freshwater habitats and the approach politicians have taken to the issue. He said the Green Party's announcement went a long way beyond what the Government was promising through the recently approved national policy statement on freshwater.
The targets set in that document were "nonsense", Joy said.
He had calculated that 99.5 per cent of New Zealand waterways already met the targets in the national policy statement, thus it would have no impact on cleaning up waterways.
Green Party co-leader Dr Russel Norman said the policy announced yesterday offered voters a stark choice on September 20.
"The Green Party will establish national standards for water that are robust enough to make rivers clean enough to swim in," he said.
"At this election voters have a clear choice, National's rivers that are so polluted you can only dip your toe in them, or the Greens' plan for clean rivers you can swim in."
Among the proposals from the Green Party was the establishment of a protected rivers network to permanently safeguard some rivers similar to the permanent protection given to national parks.
The protected rivers network would place restrictions on irrigation, dams and pollution, while retaining the ability for New Zealanders to use the rivers for food gathering and recreation.
Joy welcomed the suggestion. However, he said this protection had to be extended over the whole river, not just the upper reaches.
An estimated 74 per cent of New Zealand's native fish species were classed as threatened, he said. Many species, such as inanga, used the full length of a river as habitat during their life cycle.
National Environment Minister Amy Adams rubbished the Green Party's plans, calling them anti-jobs and anti-growth.
"Improving the quality of our freshwater is important to us all but the Greens' approach is costly and impractical," she said.
"Approaching improvement through blanket bans and requirements for every drainage ditch across New Zealand to be maintained at a swimming pool standard just shows that the Greens have once again confirmed they are the anti-growth party."
Federated Farmers environment spokesman Ian McKenzie said the one-size-fits-all approach the Greens had taken would be unable to be implemented nationally because of the cost, he said.
"This Green Party policy intent shows a lack of integrity. It cannot be implemented fairly without a huge cost to society and will likely only end up being implemented in rural areas instead of all waterways."
Professor Mike Joy is speaking at Te Manawa at 7.30pm tomorrow as part of a national speaking tour of Royal Society of New Zealand branches.
- Manawatu Standard
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