St. George's main wastewater pipeline is within 5% of capacity, according to city officials, prompting a $40 million expansion project that will replace more than 20,000 feet of pipe serving four Washington County communities. The pipeline, first built in 1990, carries sewage from St. George, Ivins, Santa Clara and Washington City to the region's treatment plant, and officials say growth across the area is pushing the aging line toward its limit.
City Water Services Director Scott Taylor said the region's growth is increasing wastewater flows to the treatment plant, according to KUTV. The project will upsize the main line from a 48-inch to a 66-inch diameter pipe, according to a notice filed with Utah.gov.
Why the Route Changed
The project's route is not detailed in the state filing.
The pipeline replacement itself has two phases, with the city hoping to begin phase one construction in 2027 and phase two in 2028, per the station's report.
Who Pays and How
Users in St. George, Ivins, Santa Clara and Washington will all pay the same rate for the project, which will be funded through user rates from existing customers and impact fees from new users, the outlet reports. St. George also has reserves built up from collecting user rates and is seeking grant opportunities and other funding sources to help cover costs. Taylor said the city updates its master plans at least every five years to keep pace with changing demand.
Taylor expects the new pipeline's size to handle growth without requiring further upsizing, and separately projected that the wastewater treatment plant itself will need expansion in roughly 10 to 15 years. Noah Bernstein said St. George should continue monitoring the pipeline because population growth could still change the plan, the article notes.
A System Already Under Strain
The wastewater system is already under strain.
The regional reclamation facility itself has a long history of expansion to match growth. It opened in 1990 with a treatment capacity of 5 million gallons per day and has since grown to roughly 25 million gallons per day, according to historical context compiled by the Utah Department of Environmental Quality. The regional collection system now spans more than 560 miles of underground piping, with the average household generating about 110 gallons of wastewater daily, according to the City of St. George.
Growth, Regulation and Reuse
Washington County's population reached an estimated 213,670 residents in 2025, per USAFacts. St. George and neighboring Washington City are part of the region's rapid growth.
Beyond simply handling more volume, the reclamation plant also plays a role in water conservation in the desert climate, converting treated effluent into reclaimed water for irrigation at city parks, golf courses and public schools, per the City of St. George. Recent EPA regulations have required the facility to cut allowed phosphorus concentration in effluent released to the Virgin River from 2.5 milligrams per liter to 1.0 milligram per liter, the city notes.
