CANON CITY, Colo. (AP) – Opponents of a plan by the artist Christo to hang nearly 6 miles of silvery fabric in sections over the Arkansas River say the project is still a danger to fish and visitors and they are considering an appeal after a federal judge refused to intervene.

Members of Rags Over the Arkansas River, also known as ROAR, filed the lawsuit, contending the project threatens bighorn sheep, public safety, traffic on U.S. 50 and businesses that depend on the scenic river to draw anglers, rafters and tourists.

A federal judge ruled Friday that there is no evidence federal officials failed to comply with environmental laws, as opponents said in their lawsuit.

Artist Christo speaks at a press conference unveiling two original preparatory collages for 'Over The River' donated to the National Galley of Art's permanent collection by French environment artist Christo at the National Gallery of Art on November 8, 2011 in Washington, DC.  (Photo by Riccardo S. Savi/Getty Images)

Artist Christo speaks at a press conference unveiling two original preparatory collages for ‘Over The River’ donated to the National Galley of Art’s permanent collection by French environment artist Christo at the National Gallery of Art on November 8, 2011 in Washington, DC. (Photo by Riccardo S. Savi/Getty Images)

“We have one lawsuit in state court still outstanding, but today we took a very significant and important step forward in realizing Over the River,” Christo told The Pueblo Chieftain.

Christo has not specified a date for the exhibition. He has said he would need at least 27 months if all legal obstacles are cleared.

A Colorado judge has already ruled the state acted properly while giving its approval to the project.

The opposition group claimed that the U.S. Bureau of Land Management violated federal law by failing to comply with the Federal Land Policy and Management Act and the National Environmental Policy Act. The judge disagreed, concluding that bureau did not violate the laws.

In a statement Saturday, members of ROAR said that although the court found the project technically complied with federal law, it did not dismiss concerns over the destructive nature of the project.

The project is expected to be displayed for two weeks in the month of August, when the river would be calm enough for rafters to peer up at the fabric as they float underneath and when drivers on U.S. 50 along the river could look down.

Christo and his late wife, Jeanne-Claude, began scouting for a location for the temporary installation in the 1990s. After visiting 89 rivers in seven states, they chose the Arkansas River between Salida and Canon City.

CORRECTION: In an earlier version of this story The Associated Press reported erroneously that Christo said the project could proceed as soon as August 2018 if he wins a state court lawsuit. Christo has not specified an exhibition date.

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