The Green Party says it's time to get tough on water management and the dairying and clean streams accord.
The accord was signed in 2003 by Fonterra and government agencies and and councils. It will expire next year.
An annual snapshot report by Fonterra shows that dairy cattle are now excluded from waterways on 84% of farms.
But Green Party co-leader Russel Norman says the self-reporting approach of the Accord makes the figures unreliable.
He says stronger regulations are needed.
The dairy industry is now considering what should follow the accord when it expires next year. An announcement is due late next year.