Areas of Williamson County's water future flow through BRA expansion

To quench the thirst of the swelling Williamson County population, the Brazos River Authority has several major projects underway to dramatically increase how much water it can treat and distribute. The work will ensure a continued reliable water supply for BRA’s East Williamson County customers.

Eastern Williamson County was seeing modest population growth, but that changed when, in November 2021, Samsung Electronics Co., Ltd. announced it would build a new semiconductor manufacturing facility in Taylor, said Brad Brunett, BRA's chief operations officer. This Taylor facility would be Samsung's largest-ever in the U.S. While the BRA isn't supplying Samsung with water for its manufacturing processes, the move is bringing thousands of people to the area to construct the manufacturing facility, work there, as well as supporting businesses, which all would need water.

And since the announcement, growth projections for the area dramatically changed, Brunett said. This meant the Brazos River Authority needed to reevaluate its East Williamson County Regional Water System (EWCRWS) capacities.

"We've got a lot of growth out there and we're going to need to increase the capacity in a very short period of time," Brunett said. "Within the next five years, we'll be going from 14.5 mgd (million gallons per day) to about 30 mgd."

The EWCRWS has several components: An intake structure on Granger Lake pumps raw water 3.6 miles by pipeline to the water treatment plant. Treated water is then pumped 3.7 miles away from the plant to customer access points in Circleville.

The BRA supplies water to the city of Taylor, the Jonah Water Special Utility District, and the Lone Star Regional Water Authority via the EWCRWS. Through these providers, an even larger population is served. The city of Taylor also supplies some water to the city of Hutto, Jonah Water Special Utility District covers a large geographical area, and the Lone Star Regional Water Authority is a regional provider for Bell and Williamson County, supplying water to the city of Jarrell, Jarrell-Schwertner Water Supply Corporation, Sonterra Municipal Utility District, and others.

The BRA purchased the water treatment plant adjacent to Granger Lake from the city of Taylor in 2004, Brunett said. The organization then began a $17.4 million expansion from about 5 mgd to almost 13 million mgd to meet the area's growing needs.

"We also built a new intake structure, added back-up generators, and made some other major improvements out there to ensure a dependable water supply into the future," Brunett said. "We've had a good track record of providing reliable, high-quality water to our customers over the last 20 years."

So begins a series of expansion projects.

In 2023-2024, the BRA underwent a re-rating process with the Texas Commission on Environmental Quality – essentially testing to demonstrate that the plant was capable of treating more water than its stated capacity – and through that, brought the rate up to 14.5 mgd, Brunett said.

Meanwhile, the BRA has completed design work for a groundwater blending project and will soon request bids with the goal of construction being completed in the latter part of 2026, said Mandy Cullar, program manager.

The project will add a 35-foot-tall cooling tower and disinfection equipment, allowing the BRA to use water from its Trinity Aquifer well to supplement the treated Lake Granger surface water supply, Brunett said. The groundwater will be cooled, chemically treated, and blended with treated surface water prior to delivery.

"The water that comes out of the well will be about 112 degrees Fahrenheit," Cullar said. "That well is about 3,300 feet deep, and the closer to the center of the Earth, the hotter that water is."

In order to efficiently and effectively disinfect the water, it needs to be cooled to between 80 -90 degrees Fahrenheit, Cullar said. Otherwise, when chlorine is added during the disinfection process, it would burn away due to the high temperature, she said.

That blending ratio will be limited to a maximum of 28% groundwater to 72% surface water due to the high total dissolved solids (TDS) content of the groundwater, she said.

"If you were to use that well without blending with the treated water from the lake, you'd have to put in a pretty expansive treatment process due to the high TDS salt levels," Brunett said. "As long as we keep the blend ratio below a certain level, the finished product will be high-quality water that meets regulatory standards.”

Once this is online, it will bring the total treated water capability of the system up to about 15.25 mgd.

Once that project is complete, a new treated water pipeline will further increase the treated water capacity capable of being delivered to the customers.

The BRA currently has one treated water pipeline that is used to deliver water from the plant to the customers. This pipeline was originally constructed around 1990. The 27-inch line is nearing capacity and is currently the only dedicated means of delivering treated water. If the line were to break or fail, thousands of households could temporarily be without water.

Therefore, the BRA is working to build a second treated water pipeline. Engineering design for this project is underway and is expected to be complete in 2026. Upon completion of the new 48-inch line, the existing 27" line will be used to supply the city of Taylor, while Jonah Water SUD and Lone Star RWA will utilize the new 48-inch pipeline. Interconnections between the lines will be included to provide redundancy for all customers, so that, essentially, if something were to happen to one pipeline, another is available until the first is repaired.

The new pipeline will initially increase the East Williamson County Regional Water System delivery capacity to approximately 18.5 mgd.

Up next is an expansion of the surface water treatment plant itself.

This project, which is expected to be completed in 2028, will increase the System’s plant capacity to approximately 30 mgd.

Roughly 95% of the design has been completed, and a request for bids for construction is expected to be issued next year, said Aaron Vaughan, project manager.

This work will involve adding two clarifiers, four filters, and another ground storage tank to the plant, along with additional piping and pumps, among other enhancements, Vaughan said.

Future expansion of the System beyond 30 mgd will depend on how customer demands play out over the next 10 years or so, Brunett said. It's considered Phase 3 and could bring the total System capacity to 40 mgd or more, he said.

Phase 3 could begin as soon as the previous project is finished or could be done at a later time, Vaughan said. "It's all based on the need for this service area," he said.

"This demand for water, both now and in the future, is due to the large population growth in Williamson County and along Interstate-35 and the arrival of Samsung," Cullar said. "With Samsung, it really was the residual effect of their arrival. It is a 'If you build it, they will come,' situation. People want to live close to where they work. Supporting industry moves to the area. Other industries move to the area because Taylor is now on the map and one of the places people want to be."