CHEYENNE -- Wyoming Attorney General Pat Crank claims the U.S. Supreme Court should refuse to hear a water rights lawsuit brought by neighboring Montana.

In a filing Friday, Crank rejected claims by Montana Attorney General Mike McGrath that Wyoming has used more than its fair share of water from rivers the states share. That violates a 57-year-old interstate water compact between the two.

Water disputes are becoming an increasingly common feature of the west's legal landscape as developing states struggle to meet growing demand in a naturally dry region. Idaho's Supreme Court recently issued a landmark ruling on a similar in-state issue.

McGrath filed suit with the U.S. Supreme Court in January claiming Wyoming farmers and methane drillers over-consumed from the Powder and Tongue Rivers, which flow from northeast Wyoming into southeast Montana. McGrath claims this water should be counted against Wyoming's share.

But Crank claims water pumped from underground aquifers by farmers and drillers isn't covered by the 1950 Yellowstone River Compact and therefore can't be counted, the AP reported Saturday.

"Montana's claims lack sufficient seriousness or dignity to justify this Court's exercise of its original jurisdiction," Crank's Friday filing stated.

McGrath and his staff are analyzing the filing and intend replying in around two weeks. "We're confident the Supreme Court will accept jurisdiction," McGrath told the AP. "They owe us more water in both the Tongue and the Powder."

The case is similar to one decided by the Idaho Supreme Court early last month and reported in LegalNewsLine, in a dispute between upstream surface-water users and downstream underground-aquifer users. There the court ruled for the downstream users but mediations continue.

McGrath's suit went directly to the U.S. Supreme Court because the Yellowstone River Compact Commission has twice before declined to hear Montana's complaint over the two rivers.