Water belongs to all New Zealanders, "it's part of our Kiwi heritage", he said.
"We are not going to take water use in this country."
With modern science and technology, and "town and country" working together, New Zealand's water quality can be improved, Peters said.
But targeting farmers only, was unfair, he said.
Waterways would be electronically-monitored in real time, Peters said, and to introduce management plans that take town and country equally.
He said the provinces and regions of New Zealand were the "lifeblood of the country", and needed protecting.
"You burn down the provinces, this country is finished."
Peters also said he would not support Labour's proposals to widen the scope of the Emissions Trading Scheme.
To boost environmental sustainability on the farm, New Zealand First says it will commit to 100 per cent depreciation for farm environmental works done against a farm environment plan.
Irrigation New Zealand said it invited the leaders of the main political parties to attend forums with local farmers on water issues.
National leader Bill English spoke to farmers in Ashburton last week. He faced questions about what National was doing to counter Labour's plans for a water tax.
English today said there was some pressure on Peters to make any bottom lines he had around taxes clear.
"There are any number of people now, particularly in the regions, whose support he had cultivated who are now really concerned that if Labour gets in they end up with this bunch of new taxes."
He said Peters was asked about those taxes at the Morrinsville rally: "now that will help them decide."
He said it was up to the voters to decide if Parliament would be better off without NZ First. "I think the country would be better with a strong National Government so we can get on with building on the strength of this economy."
Labour Leader Jacinda Ardern reportedly declined. Labour's environment spokesman David Parker and primary industries spokesman Damien O'Connor had already spoken to farmers in Ashburton at an event last month organised by Federated Farmers.
An Irrigation NZ information pamphlet, entitled 'We don't support a water tax!', was placed on each seat.
Irrigation NZ chair Nicky Hyslop said everyone, including farmers, want clean rivers, but "the proposed water tax just won't do that".
The Canterbury region would be hardest hit by the introduction of any water tax.
Irrigation NZ says an average-sized irrigated farm in Canterbury (220ha), would pay $24,000 - $29,000 in tax, at 2c per 1000 litres.