Māori proprietary interests in water bodies have been made to government since the 1860s and such interests have been recognised by the Waitangi Tribunal since at least 1992.

The issue was brought to a head because of government delays in responding to the Tribunal findings, the ongoing impact of the Resource Management Act and, eventually, the Government decision to sell shares in power companies that utilise water bodies in which Māori claim proprietary interests without first examining those claims.

The claim taken in the Tribunal was that hapū and iwi have proprietary interests in various water bodies, meaning awa, roto, puna, ngawha and repo (rivers, lakes, cold springs, hot springs and wetlands).