Approximately one million gallons of orange-colored mine tailings wastewater has spilled into the Animas River in southwestern Colorado, forcing several river recreation businesses to close and irrigation companies to suspend water delivery to hundreds of local farmers.

A team of Environmental Protection Agency (EPA) regulators probing contamination at the abandoned Gold King Mine in San Juan County on Thursday accidently released the wastewater into Cement Creek, which flows into the Animas River, EPA spokesman Rich Mylott said.

Most of the wastewater, which contains heavy metals and other toxins that can be harmful to humans and aquatic life, spilled into the creek within an hour, the EPA said in a statement on Friday. Though a lighter flow of contaminated water continues to flow into the creek, the agency has begun diverting it into a settling pond.

In an attempt to control the impact of the spill, Sheriff Sean Smith of nearby La Plata County on Thursday issued an order closing the Animas River to the public from the north county line (San Juan County) to the Colorado-New Mexico border in the south, according to a statement published on the La Plata County website.

“This decision was made in the interest of public health after consultation with the EPA, the Colorado Department of Health and Environment, San Juan Basin Health Department and representatives of the Southern Ute Indian Tribe,” Smith said in the statement.

The order would be reevaluated after the EPA announced water test results, Smith added. Initial EPA tests have detected various levels of lead, arsenic, aluminum and copper in the river.

The agency said it was testing water samples as far downstream as New Mexico to determine when the wastewater had diluted sufficiently enough for the river to be declared safe again. Results were expected as early as Friday evening.

In the city of Durango, about 50 miles downstream from the Animas River and 30 miles north of the New Mexico border, locals told Al Jazeera that the river’s closure had drastically impacted their livelihoods.

The spill forced local rafting and kayaking companies, a cornerstone of Durango’s economy, to cancel tours and rental services indefinitely.

“This is costing us thousands of dollars a day and I can’t get a straight answer out of anyone — I’m seriously angry,” Tom O’Keeffe, owner of the Durango Rafting Company, told Al Jazeera.

Another Durango water recreation company, 4 Corners Whitewater, also shut down its rafting operations since the bright orange wastewater flowed through the city.

“Everyone was kind of in awe. There were about 50 people standing on the bridge waiting for it to come through,” said Logan McGlamery, an employee of 4 Corners Whitewater.

“We’re definitely losing a lot of business here,” McGlamery added. “It’s pretty incredible, like nothing we’ve seen.”

Local farmers have also been negatively impacted by the river’s closure.

City officials said Durango had stopped pumping water from the Animas River and was instead drawing from the unaffected Florida River, adding that the city’s tap water was safe to drink. But farmers who depend on the local rivers for irrigation said their water supply had been entirely cut off.

“We didn’t have water yesterday or today,” Jennifer Wheeling, of the James Ranch near Durango, told Al Jazeera.

“We’re waiting for the rain — that’s all we can do,” Wheeling said.

The Animas Consolidated Ditch Company (ACDC), which supplies irrigation water from the Animas River, said local emergency management teams informed farmers of the contamination within hours of the spill.

“We and other ditch companies were notified that there had been a spill into the river upstream,” said ACDC board member Ed Zinc. “We were able to close off the headgates to eliminate the water from the river from coming into our ditches and spreading onto the land.”

Zinc said his company serves 300 customers, and that there is another ditch company on the other side of the river that has also been shut down that serves fewer customers.

David Banga, president of the Durango Farmers Market, said that some local farms may be able to get water from other river sources, but further south in New Mexico, the Animas River is the sole source of irrigation water.

There has been no indication of how long the ditch companies will have to keep the headgates closed, Zinc said, adding that the river’s orange color had begun fading by Friday afternoon.

David Ostrander, the local EPA Region 8 director of emergency preparedness, said at a community meeting in La Plata County on Friday that the river’s orange hue and high toxicity levels should fade within two days, but officials would need to continue monitoring its safety for recreational and agricultural uses.

The EPA has also been consulting with the Southern Ute Tribe and the Navajo Tribe about possible contamination to their water supplies downriver, Ostrander added. The EPA Region 8 team will be in contact with its Region 6 counterpart in New Mexico as the contamination moves downstream into the neighboring state, he said.

The wastewater was just miles away from the New Mexico border on Friday morning, the EPA said in a statement, before adding that all they could do is wait for the contamination to dilute on its own.

“I’m very sorry for what’s happened, this is a huge tragedy,” Ostrander said. “It’s hard being on the other side of this … we typically respond to emergencies, we don’t cause them.”

With wire services