A battle is looming in Golden Bay over a proposal to increase irrigation,which conservationists fear will damage New Zealand's largest freshwater springs.
Te Waikoropupu Springs, known as Pupu Springs, has the clearest water in the world and attracts tens of thousands of visitors a year.
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Andrew Yuill, who was part of a working group looking at the proposals, has applied jointly with a local iwi, Ngati Tama, for a conservation order to protect the aquifer feeding the springs.
He says tests show nitrate levels in the aquifer are already averaging dangerous levels and that's a real concern.
Mr Yuill says the aquifer supplying the main spring has a 10-year flow-through time, so no-one knows what might happen further down the track.
He says the issue is not just about taking water from the aquifer, but also about what's done with the water and what goes back into the aquifer.
"You take out really clear water, you use it for farming and what goes back has all of the usual run-off from farms in it."
"It's not just what runs off the edges of paddocks and into rivers, which can be mitigated by riparian plantings, but where you've got a marble aquifer with gravel over the top of it there's also a route directly down into the aquifer."
"What we're seeing is levels of nitrate coming out of the springs at the warning levels that NIWA has given."
The Tasman District's deputy Mayor, Tim King, who also chairs the Council's environment committee says everyone in the region recognises the importance of protecting the water quality of the Pupu Springs.
He says the irrigation proposals are still being considered and there are many options for dealing with the issue.
"They include issuing a draft plan change for informal feedback or starting a legal process under the Resource Management Act, with hearings being held and a final decision made by the Council."
Mr King says the final decision would be appealable through the Environment Court.