A freshwater ecologist says draft national water objectives issued by the Ministry for the Environment are weak and do nothing to protect rivers.
The objectives are meant to set bottom lines for water quality in lakes and rivers.
But Dr Russell Death of Massey University told Nine to Noon that, rather than protecting rivers, they allow for more pollution and farm runoff.
Dr Death says that with increasing concern about river quality, there needs to be better protection.
However, the ministry says the draft objectives are not the last word.
Deputy policy secretary Guy Beatson says standards for rivers are being developed by a team of scientists who will need to agree on what the standards should be.
He says the ministry plans to issue the objectives for consultation at the end of the year.