The Maori Council has won permission to join a Supreme Court appeal on whether milk processor Synlait or Central Plains Water should have priority to draw water from the Rakaia River.
Waatea News reports Lake Waikaremoana claimant Vern Winitana and Trustpower have also been granted intervenor status in the case, which also involves the Ashburton Community Water Trust and Canterbury Regional Council.
The Maori Council deputy chair Jim Nichols says the Rakaia case raises the same issues as a case last year between Central Plains Water and Ngai Tahu Properties, which was abandoned after the parties reached a deal.
He says the court wants to hear the Maori view on how the Treaty of Waitangi may apply when natural resources are allocated.
He told Waatea News that if the Supreme Court recognises the Maori Council's position it would mean that Maori are not disadvantaged.