American Falls sewage overflow spills into parking lot, river below reservoir

AMERICAN FALLS — Sometime between Sunday night and early Monday morning, sewage overflowed from the American Falls wastewater treatment plant, spilling into a nearby parking lot and into the river below the reservoir, according to American Falls officials.

The Idaho Department of Environmental Quality was informed of the sewage spill around 8 a.m. Sunday morning, at which point the spill had been addressed by American Falls officials, the DEQ recently told the Idaho State Journal

An alarm that was supposed to sound did not go off, failing to notify the proper authorities of the incident when it occurred, the DEQ said, adding that the overflow had been discharging for one to two hours before it was discovered. The cause of the incident is still under investigation.

Following the accident, DEQ authorities, while working closely with American Falls government officials and American Falls police, warned locals to avoid wading into or swimming near the affected areas until they received proper results verifying the space was safe from E. coli contamination, the DEQ said. Boating and fishing access was still permitted.

The recent deaths of hundreds of rainbow trout in the American Falls Reservoir was not related to the sewage spill, DEQ officials said.

“The area was closed, people were asked to leave and notified of the issue,” the DEQ recently told the Journal. “It was closed for (two) days so that the river could flush the material out and basically dilute it. There’s no issues now. There shouldn’t be any impacts to the water. There is always some E. coli in the water, but of course, there was a big slug of it, but currently it is cleaned up. They disinfected the whole area of the parking lot and the wastewater treatment plant and took samples, testing for E. coli and got results back that indicated that it had cleared.”

According to a DEQ official, additional samples will be collected and tested next week to doubly ensure the safety of the area and quality of the water. The samples taken on Monday, Tuesday and Wednesday were determined to be well below the threshold for E. coli contamination.

“The wastewater treatment plant responded very quickly to the issue,” a DEQ official said. “I think it was only overflowing for an hour or two before they were notified or discovered it. They did a great job at notifying DEQ, addressing the issue and telling the public that we’re already aware of the issue. We work closely with our municipalities and respond as quickly as we can. I know the sheriffs were out there as well, talking with the public and getting that word out. I think they responded pretty quickly.”