Here’s how Washington County plans to meet a growing demand for water
Aug 14, 2023, 9:22 AM
(Jeffrey D. Allred/Deseret News)
ST. GEORGE — An influx of people to a region can be closely tied to increased water demand, regardless of whether there’s supply in place to meet that demand.
This is undoubtedly true for Washington County, one of the fastest-growing areas in Utah and the nation.
A 2022 report from the U.S. Census Bureau said the St. George area’s population grew by nearly 10,000 new residents between July 1, 2020, and July 1, 2021 — a 5.1% increase. The metro area — a statistical area that includes all of Washington County — grew to 191,226 residents, according to the report.
“None of the growth we’ve experienced would be possible without water,” St. George Mayor Michele Randall said. “Although we’ve had a very wet year this year … we still have a lot of challenges when it comes to water.”
With this in mind, the Washington County Water Conservancy District recently published a 20-year plan to guide the county to ensure it has the necessary water supply to meet the growing demands associated with an increasing population.
In 2022, the county banned “nonfunctional grass” at new commercial, institutional and industrial developments — limiting grass at new homes under a new ordinance.
The new ordinance — which also bars new golf courses unless the developers can provide their own nonpotable water source for irrigation and require secondary and reused water for outdoor irrigation “where available” — is projected to help conserve nearly 11 billion gallons of water over the next decade, according to the district.
Despite enjoying state-leading levels of snowpack runoff, (an essential source of water for the region) drought conditions are starting to again creep up in southern Utah, with the U.S. Drought Monitor classifying Washington County as “abnormally dry.”
So, just how does Washington County plan to protect and improve its water supply?
Lake Powell Pipeline problems
In 2022, the county created a Regional Water Master Plan that was heavily contingent on the Lake Powell Pipeline being in operation by 2035.
“While (the pipeline) remains a critical component for meeting Washington County’s long-term water supply needs, a number of recent hydrological, environmental, and political issues impacting the Colorado River Basin have introduced uncertainty regarding the timing and yield of that project,” said the plan.
Considering these hangups, the county is evaluating its alternatives when it comes to securing water supplies to meet the demands of the next 20 years — focusing on existing and future potable water supplies and facilities to meet demands.
In May, Utah Gov. Spencer Cox issued an executive order to have every state agency assess “its compliance with water conservation requirements for state facilities,” including following the Utah Division of Water Resources’ weekly watering guide.
These conservation goals are essential to meet Washington County’s water needs. The county has adopted a goal that strives to reduce the average per capita water use by an additional 23% by 2070.
“(Water conservation) is expected to generate about 11,400 acre-feet per year of additional supply, primarily through the district’s lawn replacement program plus a variety of other measures, including reducing system loss, improving existing water conservation rate structures and installing advanced metering infrastructure meters,” said the plan.
The plan anticipates that average water use will gradually decline as a result of conservation measures, and while not certain, is definitely achievable.
The Washington County Water Conservancy District and its Regional Water Supply Agreement partners are also looking to lean on and develop regional water reuse systems to optimize water use in the county.
The regional reuse system will produce about 24,200 acre-feet per year of additional supply, through the construction of new treatment facilities, pipelines, and storage reservoirs to capture reuse water and put it to use for agricultural and irrigation purposes, freeing up water for drinking,” said the plan.
Currently, the St. George Regional Water Reclamation Facility treats about 12.5 million gallons of wastewater per day from St. George, Washington, Santa Clara, and Ivins while the Ash Creek Special Service District treats about 2.7 million gallons of wastewater per day flow from Hurricane, La Verkin and Toquerville.
Reusing wastewater was also a topic that was heavily discussed by Randall and other cirt leaders at the St. George State of the City address in February.
“You can actually treat this water and make it potable. That’s what they’re doing in Las Vegas, and I know it sounds horribly disgusting but it just might come to that with water,” Randall said.
Additionally, Randall said that the city would be retrofitting four oxidation ditches to give them the capacity to treat 24 million gallons of wastewater per day. Previously, the oxidation ditches only had the capacity to treat 17 million gallons of wastewater per day.
Water supply development
In addition to conserving water and finding new ways to reuse wastewater, Washington County is also looking for better ways to store it.
According to the plan, potable water development projects — including the new Toquer Reservoir, expansion of the Sullivan/Cottom Wells, Cove Reservoir in Kane County, redevelopment of the Ence Wells and a well in Diamond Valley — will add around 4,800 acre-feet per year of additional water.
Storage was also a topic Randall and other city leaders touched on at the State of the City address, where Randall said that the city is planning to build a reservoir on city-owned property near Graveyard Wash off Old Highway 91 to store reuse water.
“It’s going to store up to, I think, 12,000 or 14,000 acre-feet of water. During the winter, we can pump our reuse water up to this reservoir and save it for the summertime,” Randall said. “Right now, we’re just treating that water and sending it downriver to Lake Mead.”
Municipal groundwater optimization
The municipalities within the county have about 6,624 acre-feet per year in water rights that are not utilized due to uncertainty about the reliability of the groundwater sources, but hydrologic studies referenced in the plan suggest that some or all of this water could be reliably available from year to year or with additional infrastructure investments.
Optimizing the region’s municipal groundwater could add an additional 3,000 acre-feet per year to the county’s water supply “if it is determined that the area’s groundwater rights may reliably generate more supply than current working estimates,” according to the plan.
The full 20-year plan with more details and information can be found here.