SALT LAKE CITY — The U.S. Supreme Court is set to hear arguments Tuesday in a case that could have implications for states that rely on interstate water compacts.

Utah officials are among those taking an interest.

Utah joined six other states that weighed in together on the Tarrant Regional Water District vs Hermann case that pits the water supplier for much of the Fort Worth-Dallas area against the state of Oklahoma.

At issue is an interstate compact governing the division of excess runoff water that is to be shared equally by four states: Oklahoma, Arkansas, Texas and Louisiana.

Drought-stricken Texas is facing the prospect of critical water shortages in the coming decades and is acting now to claim its share under the provisions of the Red River Compact.

"All of the studies we have conducted in conjunction with Texas show this will be among the fastest growing areas in the nation," said Tim Bishop, an attorney representing the water district. "We will be seriously water deficient in the middle of this century."

The Texas district wants to dip into its share of Red River water by taking its fourth of the flow in Oklahoma. Oklahoma has responded that the district has no authority or right to cross the border to meet Texas water needs.

Oklahoma lawmakers, acting to protect their water resources, passed a moratorium on any water exports from the state, unless those exports have their express approval.

Bishop said the state's actions fly in the face of the compact's provisions, shunning a congressionally mandated binding agreement.

"Oklahoma has made no bones about the fact that it is no intention of providing water to Texas, water that is critical to the state of Texas."

Tarrant water district filed suit over its inability to get water in a dispute that was ultimately upheld in Oklahoma's favor at the 10th Circuit Court of Appeals in December. The district is now challenging that ruling, which Bishop says threatens the sanctity of other multistate water sharing compacts.

"If the 10th Circuit was right, and at any time states can take their water and go home, why did the Red River negotiators and legislatures bother to grant equal rights to the four states to the use of that water within a defined sub-basin?" Bishop questioned.

He asserts that if the Court of Appeals decision is allowed to stand, it will create chaotic circumstances among regions that depend on water-sharing agreements — akin to lighting a match in a tinderbox ripe for fiery disputes.

The legal team points to areas like Denver and the Salt Lake City metro area as regions that depend on water supplies governed by interstate compacts — such as the Colorado River compact of 1922 that allocates that water among seven recipient basin states, including Utah.

But Utah actually joined with Colorado, Idaho, Nevada, New Mexico, Indiana and Michigan in urging the high court to refrain from unraveling the 10th Circuit decision.

"We have a very strong interest" that Oklahoma's position be upheld, said Norm Johnson, the natural resources attorney for the Utah Attorney General's Office. "A compact does not equal permission to disregard the water laws of equal sovereign (states)."

Johnson said it should be telling that both lower courts have sided with Oklahoma and respected the right of states to govern what happens to the water within their boundaries.

"It really is a question of access," he said. "If it is equitable for Texas to enter into Oklahoma to be able to access their water, the compact should have indicated that when it was written. It should not be left to a future dispute like the one underway."

Johnson, stressed too, that it is the position of the seven states that the compact's provisions should be interpreted to "mean what they say," not what they don't.

In their brief, Utah and the other states argued, "The adage 'good fences make good neighbors' aptly expresses the interests of the (seven states). … The language of the interstate compact, like a good fence, is the best tool to ensure neighborly cooperation among the compacting states in the long run."

But Bishop said the states are using the sovereignty argument to mask their own economic self-interest, and letting states' rights trump at the expense of a long-standing compact.

"There is no loss of sovereignty here. The states all agreed to the compact and agreed access is appropriate. … What's really going on here is that these are water-rich states that want to maintain control of that water so it is economically available to them."

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