An environmental accord has been signed between the Government and Tainui, as part of the Waikato River Settlement.
Legislation was passed in May establishing the Waikato River Authority, which allows co-governance of the river by the regional council and iwi groups.
The legislation provided for a $210 million cleanup fund for the Waikato River during the next 30 years.
Environment Minister Nick Smith says the accord sets in place the mechanics for ensuring the cleanup takes place.
Dr Smith says the environmental restoration of the river is core to the Government's partnership with Waikato-Tainui.