Conservation groups are worried one of the clearest freshwater springs in the world could be harmed by increased irrigation in Golden Bay.
However the council says Te Waikoropupu Springs in Takaka Valley will in fact be better protected under a new water allocation regime.
The pristine fresh waters of Te Waikoropupu Springs draw 90,000 visitors per year.
"These are the third clearest waters in the world - and for most people, these are the clearest they'll see," says Save Our Springs founder Steve Penny.
The water has a visibility of 63 metres, largely thanks to organisms called stygofauna which cleanse the springs.
But they've become a flashpoint as the Tasman District Council works on a new water allocation regime - prompted in part by high demand from farmers.
"What the dairy industry has got its eyes on is it wants to destroy 'Pupu Springs in order to have more cows to make a few extra bucks," says Greenpeace NZ executive director Russel Norman.
Greenpeace's concern stems from an informal waiting list of 12 irrigation applications for the area.
Mr Norman says allowing farmers to take more water leads to intensified dairy production, increasing the risk for waste getting into the inter-connected aquifers.
"Of course the effect of that downstream will be the springs will get full of nitrogen, and you get algae blooms and pollution - so it will destroy this national treasure," says Mr Norman.
NIWA say nitrate levels in the springs are already at critical levels.
Mik Symmons sits on the council's fresh water advisory group and says irrigators will likely get more water - but overall water quality is still a priority.
Those concerns are shared by local iwi Ngati Tama, which has filed a Water Conservation Order with the council to protect the Takaka Marble Aquifer which feeds the 'Pupu Springs.