The Green Party wants to clean up 10 of New Zealand's most polluted rivers and make them safe to swim in again.
At the party's annual conference in Christchurch on Sunday, co-leader Metiria Turei launched the campaign and attacked the Government's track record on the environment, saying National had given up on clean rivers.
"Rivers can be clean enough to swim in, but only if the Government lifts its 'wadeable' standards and demands they be swimmable instead," Ms Turei said.
"Under National nearly two-thirds of our rivers are unsafe for swimming. New Zealand needs a government to back our rivers and to stop defending polluters."
As part of the campaign, the Greens have targeted 10 dirty rivers up and down the country - including the Waikato, Tukituki and Manawatu rivers.
MPs will be hitting the road to highlight what's threatening the rivers - from over-intensification of dairying and sewerage to industrial pollution - and what can be done to help clean them up and protect them.
Earlier this year Environment Minister Nick Smith and Primary Industries Minister Nathan Guy unveiled the Government's proposed new measures to improve the quality of fresh water.
They included national standards for fences to keep farm animals out of water and developing better water management practice guidelines and efficiency standards for water use.
But the Government opted to keep the clean water standard at "wadeable", rather than lifting it to "swimmable".
In last month's budget, Dr Smith announced $100 million of funding over 10 years for a new contestable fund to clean up rivers, lakes and aquifers.
Ms Turei said that was a "drop in the bucket" of what is needed to make rivers safe for swimming.