Supreme Court greenlights Nebraska lawsuit against Colorado over water access

Josh Reyes
6.29.26
Omaha World Herald

LINCOLN — The U.S. Supreme Court on Monday granted Nebraska’s request to sue Colorado over long-ago negotiated access to water from the South Platte River, which flows east through Colorado and into Nebraska. 

Nebraska Attorney General Mike Hilgers called the decision “huge news” in a statement on social media site X. 

In this file photo, Nebraska Gov. Jim Pillen and Attorney General Mike Hilgers announced the state will sue Colorado over water access and a major canal project, alleging Colorado is withholding water and impeding development. 

“We now get the opportunity to vindicate our water rights in front of the highest court in the land,” he said.

Colorado and Nebraska signed the South Platte River Compact more than a century ago, allotting Nebraska 120 cubic feet per second of water flow each irrigation season from April 1 to Oct. 15. Nebraska has accused fast-growing Colorado of letting other water users intercept the flows belonging to Nebraska. The state estimates Colorado has deprived Nebraska of more than 1 million acre-feet of water since the compact was enacted in 1923.

Nebraska Gov. Jim Pillen and Hilgers announced their intent to sue Colorado last July.

“It’s crystal clear. Colorado has been holding water back from Nebraska for almost 100 years and getting more and more egregious every single day,” Pillen said when announcing the lawsuit. 

He also said Colorado had impeded progress on the Perkins County Canal project to carry water from the South Platte River in eastern Colorado to western Nebraska, where it would be stored in reservoirs and eventually returned to the river.

The Perkins County Canal would be the largest infrastructure project in Nebraska history and is expected to cost more than $628 million.

The high court’s order states Colorado has 30 days to file a response to Nebraska’s lawsuit.

Colorado Attorney General Phil Weiser quickly downplayed the significance of the court’s decision.

“Today’s court decision merely opens the door for Nebraska to bring its claims against Colorado. Nebraska’s burden to prove those claims is incredibly high and we will vigorously defend Colorado’s full entitlements under the compact,” he said in a press release. 

Weiser also said, “Colorado is complying with the South Platte River Compact and not interfering with Nebraska’s efforts to build the Perkins County Canal.” 

The Colorado AG has called the Perkins County Canal unwise and unlikely to happen, and Colorado officials have said the water that Nebraska expects from the river may not be there.

Colorado Gov. Jared Polis also said last year that Colorado complied with the compact and negotiated in good faith, while Nebraska has attempted to “intimidate Colorado landowners and damage our agricultural communities.”  

Hilgers introduced the proposal to build the canal as a state lawmaker under former Gov. Pete Ricketts in 2022. Pillen noted on social media and in a press release Monday that he increased funding for the project “to expand its capacity to benefit western Nebraska farmers and producers.” 

Democratic lawmakers over the past two legislative sessions have suggested drawing funds from the $628 million Nebraska set aside for the canal to shore up major funding gaps in the state budget. But the proposals never approached receiving majority support, with GOP lawmakers and the governor calling the money off-limits.

State Sen. Paul Strommen of Sidney said in March that protecting those dollars shows Nebraska is invested in its lawsuit against Colorado. 

“If we start draining that fund, the opposition could step up and say, ‘Maybe they’re not serious about this,'” he said.

The above map shows Nebraska’s preferred Perkins County Canal route from northeast Colorado. It would leave the South Platte River near Ovid, as required by the 1923 South Platte River Compact, enter Nebraska in southeast Deuel County and run through much of Keith County before rejoining the river southeast of Roscoe. 

NEBRASKA DEPARTMENT OF WATER, ENERGY AND ENVIRONMENT

Nebraska has developed plans for the canal and submitted them to the Army Corps of Engineers for environmental review. It showed the plans, including the proposed 60-mile canal path, to the public at a series of events in Julesburg, Colorado, Ogallala and Kearney. The state still must acquire privately-owned land in Colorado and Nebraska along the canal’s planned path. 

Pillen has projected that the canal would finish construction in 2032.