Washington County, Utah, one of the fastest-growing corners of the American Southwest, has awarded a contract to dramatically expand its main drinking water treatment plant, a move amid a population that has more than doubled since 2000 and a Colorado River system that keeps shrinking.
The Washington County Water Conservancy District selected a contractor to build Phase 3 of the Quail Creek Water Treatment Plant expansion, pushing the facility's capacity to 90 million gallons per day. The project also adds ozone disinfection, a technology that handles algal toxins, taste-and-odor problems, and emerging contaminants more effectively than conventional chlorine treatment and produces fewer regulated chemical byproducts. The notice of award is posted on the District's procurement page. The specific contract value, contractor name and construction timeline were not included in the public notice and would need to be confirmed directly with the District.
The urgency behind the project is straightforward. St. George, the county seat, has ranked among the top five fastest-growing U.S. metro areas for more than a decade. The county's population has grown from roughly 90,000 in 2000 to more than 200,000 today, with projections suggesting it could double again by 2065. All of that growth depends on a single watershed: the Virgin River, a Colorado River tributary that feeds Quail Creek and Sand Hollow Reservoirs.
The ozone addition also addresses a water quality problem that has become harder to ignore. Quail Creek Reservoir has experienced algal blooms and taste-and-odor episodes linked to warmer temperatures and lower water levels, conditions worsening as the region dries out. Ozone neutralizes the cyanotoxins those blooms can produce and satisfies tightening federal surface water treatment standards.
The expansion takes on added strategic weight because the District's long-sought alternative supply, the Lake Powell Pipeline, a proposed 140-mile conduit from a reservoir that is itself near historic lows, remains stalled in federal review and interstate negotiations. With that project in limbo, as explored in earlier coverage of St. George's push toward alternative water sources, maximizing output from existing Virgin River supplies has become the more immediate priority.
This Phase 3 award follows earlier construction phases that began in 2022. Whether the expanded plant will keep pace with the county's growth rate, and what role the Lake Powell Pipeline or water recycling will ultimately play alongside it, remains the central question in Washington County water politics.
