Sedona AZ (August 4, 2021) – Water quality counts taken between 9:45 a.m. and 12:10 p.m. on Thursday, July 29, 2021 show E. coli levels at all test sites were below the state and federal water quality E. coli limit of 235 Colony Forming Units (CFU)/100mL of water for recreational swimming. This is believed to be due from the lack of heavy rain in the three days leading up to the test, unlike the weekend prior. The city measured E. coli one last time as an additional precaution after testing on July 24 and July 25, 2021:
The 235 CFU/100 mL of water limit is a surface water quality standard specific to E. coli set to protect public health.
A map of the testing locations:
Background
At around 4 p.m. on July 23, 2021, rain water inundated the city of Sedona’s El Camino Lift Station at 700 El Camino Rd. and overwhelmed the pump system, causing a sewage spill to occur. The spill was stopped within 30 minutes.
It is estimated approximately 1,500 gallons of untreated liquid effluent spilled into a nearby wash. That wash flows into Carroll Canyon Wash, which ultimately drains into Oak Creek near the Crescent Moon Ranch area, approximately 2.7 miles downstream. The untreated liquid effluent entering Oak Creek was highly diluted by the rain occurring at the time of the spill.
For context, the volume of effluent translates to approximately 0.11 cubic feet per second. For comparison, Oak Creek’s rate of flow during this rain event was just under 900 cubic feet per second.
More information
These results were sent to the Arizona Department of Environmental Quality (ADEQ). Residents should take caution when recreating in Oak Creek after storm events when E. coli levels are highest.
The city took signage down warning of high levels of E. coli near Crescent Moon Ranch swimming area.
The city does not plan on reporting additional E. coli results for this incident. For sewer spill emergencies, call the city’s sewer emergency hotline at (928) 203-5180.