Nebraska asks Supreme Court to preserve lawsuit against Colorado

Nebraska officials are urging the U.S. Supreme Court to reject a request from Colorado to dismiss part of the state’s lawsuit over the South Platte River.

Official response and confirmed impact

Nebraska claims Colorado is not delivering the amount of irrigation water this state is entitled to under the South Platte River Compact.

The disagreement, which dates from a lawsuit Nebraska filed in July 2025, centers on Colorado’s “augmentation” system, which allows certain farmers to use water in the irrigation season if they replace it in the off-season in time for it to seep back into the river for the next irrigation season.

Colorado says that’s scientifically sound. But Nebraska says this “labyrinthine” system makes it impossible to verify if Colorado is complying.

Colorado claims that Article VIII does not limit how that state's officials can ensure Colorado complies with the compact.

Incident under investigation

Colorado says it is complying with the compact. In a court filing filing Monday, Nebraska argued the Supreme Court should continue to review its claim.

Colorado has requested the Supreme Court dismiss Nebraska's claim under Article VIII of the compact, which requires Colorado officials to deliver water across the state line without requiring special legislation from the Colorado General Assembly.