A federal lawsuit pitting an angler against a landowner on the Arkansas River seeks to clarify Colorado’s murky laws governing public access to streams and rivers.

Colorado Springs fisherman Roger Hill has had repeated run-ins with Mark Warsewa, whose property spans the Arkansas River between Texas Creek and Cotopaxi. Hill likes to wade from public land nearby and fish in the river near Warsewa’s place.

“I own the bottom of the river,” said Warsewa, who bought the property in 2006.

Hill on Friday sued Warsewa in U.S. District Court, arguing the bottom of the river actually is public property. His lawyers point to a federal doctrine called “navigability for title,” which holds that if a waterway was used for commercial activity at the point of statehood, the state owns the stream bed and the public has access.

With historical records showing loggers sending hundreds of thousands of railroad ties down the Arkansas River before Colorado became a state in 1876, Hill’s attorneys hope to prove “navigability for title” and, therefore, unfettered public access.

If Hill wins, the Arkansas River could be open for wade fishing through private land, and the standard could apply to just about every Colorado waterway. It also could resolve a thorny public-access issue that Colorado’s Western neighbors — New Mexico, Idaho, Montana, Wyoming and Utah — have cleared up in recent years.

“There has been a lot of confusion around this. Private landowners have been led to believe that they have the right to block access to waterways in front of their property, but that is only true if that river was not navigable for title purposes,” said Mark Squillace, a professor at the University of Colorado Law School who, with Dillon attorney Alexander Hood, is representing Hill. “This case has the potential to bring some clarity to the law and show that, yes, like any other state in the country, we have the right to access state-owned river beds under navigability for title.”

Stream-access issues erupt every several years in Colorado. A landowner on the Lake Fork of the Gunnison River in 2001 sued to block a river outfitter from floating guests past his property. Owners at a private fishing community on the South Platte River above Cheesman Gorge once chained a gate to the riverbed to block kayakers from passing through the property.

Still, little has been done to permanently resolve stream- and river-access conflicts in Colorado. No state laws or regulations define navigability.

The Colorado Supreme Court, in the seminal 1979 People vs. Emmert case, upheld a trespass conviction against rafters who floated on the Colorado River through private property in Grand County. In 1983, the Colorado attorney general sought to clarify the court’s decision with a legal opinion that paddlers floating through public property only commit criminal trespass if they touch the river bottom. The boaters could, however, be charged with civil trespass.

Colorado still relies on the 1983 legal opinion, which is not binding and has not been tested by a Colorado court. (Colorado and Arizona recently finished below six other Western states for stream access in the annual Western States Conservation Scorecard by the Center for Western Priorities.)

In 2011, then-Colorado Gov. Bill Ritter created a River Access Mediation Commission to help resolve access conflicts between landowners and boaters. That commission has not been appointed since 2015.

The Hill lawsuit highlights “an interesting point” with the evidence of commercial activity on the Arkansas River before Colorado’s statehood, said Nathan Fey, the Colorado stewardship director for American Whitewater. But he’s nervous. A victory or loss could have sweeping impacts across the state, he said.

“Regardless of which way this goes, there’s going to be trouble,” said Fey, whose job entails traveling around the state dealing with river access conflicts on a case-by-base basis.

If Hill wins, Fey said, the next issue will be to address whether the state has the right to claim a riverbed property that previously was considered private property and how much, or if, that landowner should be reimbursed if that property is deemed public. If Hill loses, Fey said, “it could have much broader implications for a pretty robust outdoor recreation economy surrounding water in Colorado, especially on the Arkansas, the nation’s most rafted river.”

“I think there’s a lot of risk here,” said Fey, noting that wading fishermen are clearly contacting the river bottom in violation of the 1983 legal opinion and this case could force a decision that impacts floating boaters.

Warsewa, who learned of the lawsuit Friday, said he doesn’t have issues with rafters or fishermen floating the Arkansas River through his property. He does have problems with fisherman walking on the river just past the riverbank below his home. In 2015, he pleaded guilty to a menacing charge after firing a handgun when fishermen were in the water.

Warsewa said Hill has sent him documents detailing access laws in states such as Utah.

“I said, ‘Well, go to Utah then,’” Warsewa said.

Hill, who wrote a popular flyfishing guidebook for the South Platte, said he just wants to fish. He recognizes that he’s taking on an issue much broader than his pursuit of wily river trout, but he is passionate about access and spreading out on a river to limit impacts on fish at heavily trafficked public access points.

“No one wants to press this. Well, I’m 76 now — and if not me, then who?” he said. “All I would like to see come out of this is the ability to go fishing in my favorite spots legally without being threatened, harassed or shot at.”