Steeped in division for decades, the scenic Browns Canyon section of the Arkansas River is once again troubling political waters.
The latest provocation: News that President Barack Obama will use his executive authority to designate the more than 20,000-acre area as a national monument, adding a new layer of federal protection while essentially sidestepping years of gridlock.
Located between Buena Vista and Salida, Browns Canyon is home to a variety of wildlife and is perhaps best known as a popular rafting spot.
While conservationists, anglers and commercial river rafters roundly applauded the expected action in a flurry of statements issued on Wednesday, the news brought a fiery reaction from Colorado's Republican delegation.
"I'm outraged," Rep. Doug Lamborn, R-Colorado Springs, said in angry response that accused Obama of orchestrating a "land grab" that Lamborn said will restrict access to Browns Canyon. Rep. Ken Buck, R-Windsor, blasted Obama on social media outlets, accusing him of acting like a "king."
Supporters of the move say that most current uses would continue, including the administration of grazing and water rights. A National Monument at Browns Canyon has earned broad support from residents of Chaffee County, and grew out of a bipartisan movement launched in part by former Rep. Joel Hefley, a Republican and Lamborn's predecessor, advocates say.
Obama is expected to announce the National Monument designation at a Thursday stop in Chicago.
Also up for National Monument designation are Chicago's Pullman neighborhood, where black railroad workers won a historic labor agreement, and Honouliuli National Monument in Hawaii, an internment camp for Japanese-Americans during World War II.
The three sites will bring to 16 the number of national monuments Obama has created under the 1906 Antiquities Act, which grants presidents broad authority to protect historic or ecologically significant sites without congressional approval, the Associated Press reported.
Conservation groups derided attacks on the proposed monument as a "smoke screen," saying that Browns Canyon has already been under federal protection and the management of the river is unexpected to change.
Federal protections for Browns Canyon have been sought since the 1970s, said John Stansfield of the Sierra Club.
"I call it a 'big sigh' moment," he said. "In two words, it means permanent protection."
The National Rifle Association and motorized user groups were among those who spoke against previous efforts to designate Browns Canyon as a wilderness area.
River guides say the national monument designation will shine a spotlight on Chaffee County's booming rafting industry, helping to bring more visitors to the area.
"We're very excited," said Mike Kissack of the Arkansas River Outfitter Association. "It's just such a special landscape that to be able to protect it is something that will benefit not only our business and the local economy, but future generations."
Bob Hamel, owner of Arkansas River Tours in Cotopaxi and Cañon City, said it will bring more exposure to what he called "the busiest part" of the country's "busiest river."
"It will give us a little bump and a little more exposure, and that's a good thing."
The expected action comes after Sen. Michael Bennett and Gov. John Hickenlooper - both Democrats - called on Obama to use his executive authority under the Antiquities act to protect Browns Canyon. Bennett and then-Sen. Mark Udall tried and failed to pass similar legislation.