Field Trip Wastewater Treatment Plant - 11000 E. Treatment plant Drive, Prescott Valley, Arizona (Discussion Only) [Neil Wadsworth, Utilities Director]

Retired Utilities Director Neil Wadsworth commenced the tour of the Water/Wastewater Treatment Facility by providing essential safety instructions. He noted that the primary purpose of the tour was to highlight anticipated capital improvement needs over the next five to ten years. Several priority areas for investment have been identified, emphasizing the need for multiple facility upgrades.

The tour began at the headworks, where incoming water is initially screened. Retired Director Wadsworth stated that enhancements are needed to achieve finer screening and improve grit removal. He noted that the existing grit removal system requires upgrades due to sediment accumulation and that a newer system would increase capacity and efficiency.

The tour proceeded to the biological treatment process, where aeration supports microorganisms that treat wastewater. It was noted that these organisms perform specific functions but are subject to regulatory limits on nitrates and nitrites (NO2 and NO3). Town Manager Gilbert Davidson emphasized the importance of proper chemical disposal, particularly for businesses, to prevent harm to these organisms.

Retired Director Wadsworth advised that facility expansion is under consideration, potentially to the property north of the site. 

Councilmember Kiehl inquired about ownership of the adjacent parcel. 

Retired Director Wadsworth confirmed it is not Town-owned but owned by the Fain family. 

At the clarifier stage, Retired Director Wadsworth explained that water undergoes additional treatment, including press belt processing and ultraviolet (UV) disinfection. He introduced the potential use of Membrane Bioreactor (MBR) technology, noting its efficiency and smaller footprint, as well as its limitations, including cost and inability to address PFAS without additional treatment. He estimated total capital improvements at approximately $200 million over ten years and indicated that future studies and consultant support will inform a comprehensive master plan. He further noted that continued repairs to aging infrastructure are increasingly inefficient compared to expansion.

Town Manager Davidson stated that engineering evaluations will be conducted and that future discussions will include potential adjustments to water and sewer rates, capacity fees, impact fees, and project financing. Councilmember Schumacher inquired whether the $200 million estimate includes land acquisition. Town Manager Davidson responded that all costs will be evaluated and presented to Council. He added that an engineer will present options at an upcoming meeting.