The Supreme Court on Thursday ruled against the Navajo Nation, dismissing a lawsuit arguing that the federal government has the legal duty under treaties signed in the 1800s to develop a plan to provide the tribe with an adequate water supply.The ruling was 5-4 against the Navajos with Justice Brett Kavanaugh delivering the opinion of the court. Justice Neil Gorsuch filed a dissenting opinion joined by the court’s liberal justices.The suit pitted the Navajo Nation against the U.S. government as well as a handful of western states that are concerned about water allocation.“In short, the 1868 treaty did not impose a duty on the United States to take affirmative steps to secure water for the Tribe – including the steps requested by the Navajos here, such as determining the water needs of the Tribe, providing an accounting, or developing a plan to secure the needed water,” Kavanaugh wrote.The suit comes as water from the Colorado River is scarce and states located in the arid southwest are tangled in disputes concerning water allocation. The tribe claims that while the average person on the Navajo reservation uses seven gallons of water a day, the national average is 80 to 100 gallons.The nation, which extends across Arizona, New Mexico and Utah and lies within the drainage basin of the Colorado River, has signed two treaties with the United States. In 1868, the United States promised the tribe a permanent homeland.Shay Dvoretzky, a lawyer for the Navajo Nation, told the Supreme Court: that the Navajos “made clear” that they understood the “promise of a permanent homeland” in the 1800s to include “adequate water for agriculture and raising livestock. “Hauled from miles away, water can cost up to twenty times more than it does in neighboring off-Reservation communities,” he argued.He said the tribe is looking for its “fair share” of water through a "fair process."“A promise is a solemn duty, and the United States’ duty is to see that the Nation has the water it needs and the United States promised,” he said.The U.S. government had argued the tribe did not have the legal right to make the claim because the treaties at issue did not create a right for the nation to sue the government over water.Frederick Liu, an assistant to the Solicitor General, told the justices at oral arguments in March that the dispute is about “whether the United States owes the Navajo Nation a judicially enforceable affirmative duty to assess the tribe’s water needs, develop a plan to meet them and then carry out that plan by building water supply infrastructure on the reservation.”“The answer to that question is no,” Liu said.