The Gila River Indian Community says Rodney "Rod" Lewis died April 10. He was 77.
Lewis spent decades fighting for tribal water rights. The 2004 settlement gave Gila River and other tribes about 650,000 acre-feet of water per year from various sources.
Lewis said he'd hoped it would encourage tribes to return to their agricultural roots.
Lewis' son, Gila River Gov. Stephen Roe Lewis, says the settlement was one of his father's proudest moments.
“He was resolute in his dedication to fight for the water, to bring back the water to the community where we could again be a strong, self sufficient agricultural society," said Gov. Stephen Roe Lewis.
The elder Lewis also served in the Army, and was the first Native American admitted to the state bar and to win a case before the U.S. Supreme Court.
Last year, Gov. Doug Ducey appointed Lewis to the Central Arizona Water Conservation District Board, where he oversaw water delegation for the entire state.
Flags were lowered on the central Arizona reservation in honor of Lewis.