DENVER (KDVR) — The Colorado Supreme Court will take up a case that pits private landowners against people who want to use rivers that flow through their properties.

The Colorado Supreme Court announced Monday that it will review the case, which originated with a fly fisherman on the Arkansas River.

Roger Hill sued two landowners who “aggressively refused” him access to fish on a segment of the river, including through force and threats of prosecution, court records show. The landowners, Mark Warsewa and Linda Joseph, argue that the riverbed is their private property. But Hill argues the stretch of river belongs to the state, and in turn, the public has a right to use it.

Hill’s case was originally dismissed, but an appeals court ruled that part of his case had standing. The fisherman wants a judge to declare that he, as a member of the public, is not trespassing when he wades on the riverbed.

After the appeals court ruling revived the case, Colorado Attorney General Phil Weiser asked the Colorado Supreme Court to step in. Weiser’s office argues that Hill’s case could have “staggering implications for settled agreements governing the use of our state’s rivers.”

River ownership claims date back to Colorado statehood

Hill’s arguments go back to when Colorado became a state. Under a federal doctrine, navigable rivers at the time of statehood were owned by the state, while non-navigable waters were owned by the U.S. and could be granted to private landowners.

Hill argues that the segment of river in question was navigable at the time of statehood and therefore belongs to Colorado. Meanwhile, the state claims that such a declaration has never been made about a Colorado river, and the fisherman’s claims could “upset almost 150 years of settled expectations for landowners.”

Weiser released this statement on Monday:

Recreation on Colorado’s rivers is vital to Colorado’s economy and our way of life. For decades, Colorado’s legislature and executive branches have adhered to the established and existing legal policy to govern river access and have declined opportunities to alter it. In this case, our office is doing our duty to defend Colorado’s legal policy. As for any possible change to that policy, it is the province of the political branches, not the courts, to do so. Under Colorado’s current legal framework, property owners, water users, and leaders in the recreation industry have worked together to increase public access to rivers for recreation and to manage this important resource. Public calls to alter Colorado’s existing policy should be addressed by the political branches, not the courts.

Attorney General Phil Weiser