The city of Farmington closed the Animas River to recreational use Thursday and warned residents to stay out of the water after raw sewage leaked into the river Wednesday.

Steve Morse, public works director for the city of Aztec, said an electrical issue at the city’s water treatment plant Wednesday caused a breaker to trip, shutting down the plant’s pumps and knocking out the emergency notification system.

City officials are unsure exactly when the plant lost power, but Morse said it was likely sometime after 9 a.m. Wednesday. As a result of the plant being down, raw sewage started to spill into the Animas River.

Plant operators became aware of the issue around 4 p.m. Wednesday and contained the leak by 4:35 p.m., Morse said.

Based on the amount of time the plant was down, and the average flow into the plant, Morse estimated about 45,000 gallons of raw sewage went into the Animas River.

The San Juan County Office of Emergency Management notified water users downstream of Aztec, recommending people not use water for the next 24 hours, or until about 5:30 p.m. Thursday. The Office of Emergency Management said domestic drinking water supplies are safe.

The city of Farmington announced in a Facebook post the Animas River would be closed until 5 p.m. Thursday, during which time all residents were advised to stay out of the river. The city also closed all its intake pumps from the Animas River to Lake Farmington out of “an abundance of caution.”

Morse said city officials are unsure what tripped the breaker, but the plant is now fully operational.

The Animas River was flowing just under 2,000 cubic feet per second Wednesday and Thursday. Morse said those high flows likely helped dilute the raw sewage.

jromeo@durangoherald.com