Topeka ? The U.S. Supreme Court has rejected claims from Kansas that Colorado should be forced to pay $9 million in legal fees from their century-long dispute over water from the Arkansas River.

The court, in a unanimous ruling Monday, said Colorado must reimburse Kansas only for about $163,000 in payments to expert witnesses. Kansas had argued that the Supreme Court could require Colorado to pay more, despite a $40-per-day limit set by federal law.

Kansas sought reimbursement for expenses it had incurred since the 1980s. Had Kansas prevailed, the money would have been set aside to cover its future expenses from legal disputes with other states over water.

Colorado already paid Kansas more than $34 million in damages in 2005, a decade after the Supreme Court ruled that groundwater pumping in Colorado diverted millions of gallons of upstream water that rightfully belonged to Kansas.

“Despite the Supreme Court’s opinion today, I continue to fight for Kansas’ natural resources and to ensure Kansans get the water they are entitled to now and in the future,” Kansas Attorney General Steve Six said.

Colorado Attorney General John Suthers called the ruling a “bright note” in the long-running case.

“We are glad to see the Supreme Court sided with our position on the matter of expert witness fees and, as a result, saved Colorado taxpayers more than $9 million,” he said.

Six spokeswoman Ashley Anstaett said the ruling isn’t a financial hardship for Kansas.

“It’s already been paid out,” she said of the legal fees. “This case was to try to recover some of the money that we thought it would be owed.”

Legal disagreements over water use from the Arkansas River led the two states to sign a compact in 1949. Colorado’s development of 2,000 high-capacity wells near the river reduced the water available to Kansans, and Kansas sued Colorado in 1985.

After the Supreme Court’s 1995 ruling siding with Kansas over the amount of water that should have been flowing from Colorado, the two states continued their dispute over how much Colorado should be forced to pay Kansas. The witness fees have been in dispute since 2004.

A special master appointed by the high court sided with Colorado on that question, and Kansas appealed.

Kansas argued that it could recover more than $40 a day for expert witnesses because lawsuits between states over water are filed directly with the Supreme Court and not in district court first.

The Supreme Court said even if Kansas were correct, the high court would stick with the “American Rule,” under which parties in lawsuits generally cover their own costs.

“Thus, assuming for the sake of argument that the matter is left entirely to our discretion, we conclude that the best approach is to have a uniform rule that applies in all federal cases,” Justice Samuel Alito wrote for the court.