Sedona council reviews wastewater facility plan, orders soil study and utility talks

Sedona City Council on a lengthy agenda item reviewed a final Wastewater Reclamation Plant facility plan that models plant capacity, compares PFAS-removal technologies and ranks options for effluent management including additional recharge wells, delivering reclaimed water to parks and schools, and full advanced water purification (AWP) for potable reuse.

The plan, presented by Roxanne Holland, director, summarized a hydraulic and concentration-capacity analysis, tested two PFAS-treatment approaches — granulated activated carbon (GAC) and ion exchange — and scored five combined effluent-management alternatives. Holland told the council she has programmed conceptual PFAS costs into the city’s 10-year capital improvement plan and recommended further sampling and targeted pilot testing before any large-scale construction decisions.

Why it matters: the choices affect long-term water supply, wastewater rates, nearby land use at the Dells and Sedona’s role in regional water planning. The council’s direction will determine what the upcoming wastewater rate study models, what capital projects are advanced in the CIP and which partnerships the city pursues with Arizona Water Company and other utilities.

Key findings and figures from the facility plan - Capacity: City modeling shows the plant currently meets build-out hydraulic capacity for most processes; staff identified a bottleneck at the tertiary filters to the current UV system and have already included a UV replacement change order of $386,000 in the FY26 CIP to increase redundancy. - Waste strength: comparing 2012–2016 to 2022–2024 data, the plant recorded increases in several load parameters: flow +4%; chemical oxygen demand (COD) +9%; total suspended solids (TSS) +13%; volatile suspended solids +12%; ammonia/nitrate +24%. - PFAS testing: limited sampling showed PFOA levels exceeding recently adopted drinking-water maximum contaminant levels (MCLs) in some samples; staff noted that effluent concentrations can exceed influent concentrations at wastewater plants and recommended continued, budgeted sampling to establish a…