By, Arizona Department of Environmental Quality
The Arizona Department of Environmental Quality (ADEQ) confirmed the unpermitted discharge of recycled water from Johnson Utilities’ Pecan Water Reclamation Plant into Queen Creek (the wash) in the San Tan Valley area has stopped. EPCOR first notified ADEQ of the imminent discharge on February 20, 2019.
EPCOR estimates a total release of 19.8 million gallons between February 20 and February 28, 2019. There was no impact to Johnson Utilities’ drinking water systems and there was NOT a release of untreated sewage into the environment.
The unpermitted discharge of recycled water was contained in Queen Creek (the wash). EPCOR said additional releases are possible if there is heavy and/or extended wet weather in the area. Recycled water is typically used for non-potable applications, including for irrigation of golf courses and common areas within a community or in ponds at the facility to recharge the aquifer. The use of recycled water in a community is indicated by purple pipes and signage cautioning against contact with standing water and/or to not drink. If you have contact with standing water, wash hands thoroughly. ADEQ confirmed samples taken in January 2019 inside the plant meet water quality standards for A+ effluent.
A permitted discharge of this kind would be required to do additional monitoring for surface water quality standards as determined by an Arizona Pollution Discharge Elimination System (AZPDES) permit. EPCOR conducted water sampling for applicable water quality standards. Results of the samples collected at the pipe discharging water into Queen Creek show it is meeting E. coli surface water quality standards for both full and partial body contact. Further results regarding other contaminants will be available at a later time. E. coli is naturally occurring and most strains are not harmful to humans. Surface water quality standards allow a certain level of E. coli that would be expected from natural sources.
The unpermitted discharge is due to an exceedance of recharge capacity of the Pecan Water Reclamation Plant. The plant is located at 38539 N Gantzel Rd in San Tan Valley. To manage future flows, EPCOR continues working to increase recycled water capacity for local irrigation districts and farmers. EPCOR was appointed by the Arizona Corporation Commission as the interim manager for Johnson Utilities in August 2018.