Sedona officials say a debris dam formed from recent flooding prevented thousands of gallons of sewage from flowing into Oak Creek.
On Tuesday night 22,000 gallons of untreated liquid effluent spilled from the Mystic Hills Lift Station near State Route 179 south of uptown Sedona.
According to the city, the waste has pooled and some is seeping into the soil.
Officials are working with the Arizona Department of Environmental Quality on decontamination and disinfection efforts.
They say water quality samples will be collected to verify that the spill hasn’t contributed to E. coli levels in Oak Creek and results will be posted online.