Alden Williams/Stuff Ngāi Tahu is seeking a declaration of rangatiratanga over fresh water in its territories, which includes the Waimakariri River. Ngāi Tahu’s Dr Te Maire Tau has called for fewer hui and more moral backbone from the Crown as a big North Island iwi player joins the South Island tribe's freshwater court action against the Crown. Tau, one of the iwi’s leaders, says the “problem of water” is caused by decades of governmental failure and that Ngāi Tahu expects some level of regulatory, economic and fiscal control over water. Last November, Ngāi Tahu lodged a claim in the High Court at Christchurch seeking recognition of its rangatiratanga over the freshwater in its tribal area. Last week Ngāti Kahungunu, the country’s third largest iwi covering parts of Hawke's Bay and Wairarapa, joined it in the action.