Round Rock is lining up a roughly $60 million ask from the Texas Water Development Board to help bulk up the Brushy Creek East Regional Wastewater Treatment Plant by 10 million gallons per day, taking its capacity from 30 to 40 MGD. The project is one slice of a much larger buildout with total costs pegged in the low hundreds of millions, and city documents show Round Rock would take on most of that new capacity. City Council is scheduled to weigh the funding strategy and a contract amendment at its meeting Thursday.
As reported by Community Impact, the $60 million would come as a low-interest loan through the TWDB’s Clean Water State Revolving Fund and would cover a portion of the East Plant expansion costs. The same council briefing packet cited by the outlet notes a $124,980 change in costs tied to additional work by Plummer Associates and indicates the city may seek a second round of TWDB funding in 2027.
According to the Texas Water Development Board, the East Plant expansion carries a construction-phase price tag of about $117.57 million and is flagged as a priority project for the 2026 funding year. TWDB documents state the work would add a fourth treatment train along with upgraded filtration, disinfection and solids-handling in order to meet stricter effluent limits as regional flows climb.
City legislative records show Round Rock would claim roughly 90 percent of the added 10 MGD, or about 9 MGD, and would be on the hook for a proportional share of design and construction costs under supplemental contract language. The Legistar entry details the design work, while project information from Plummer outlines the cost breakdown for the expansion.
What it means for residents
The TWDB loan would trim upfront borrowing costs compared with traditional open-market debt, but in the long run it is still utility customers who typically cover debt service through rates and the utility fund. Local coverage has already tracked Round Rock’s willingness to tweak those rates as big-ticket infrastructure comes online, and utility rate planning has been central to how the city maps out its capital plans.
Background
The Brushy Creek regional system, which serves Round Rock, Cedar Park, Leander and parts of Austin, includes two treatment plants and about 45 miles of regional collection lines. The East Plant has been under phased expansion since 2020, following a 2022 hydraulic-overload response that put more pressure on regional capacity planning. City updates document the West Plant’s return to service, while Community Impact has covered earlier repairs that set the stage for the current buildout.
What's next
Council is set to vote on the $60 million loan request and the Plummer contract amendment at its Thursday meeting, which starts at 6 p.m. at Round Rock City Hall, 221 E. Main St., according to the city’s events calendar. If the application wins approval, staff would move ahead with the TWDB loan process and the environmental review steps that have already been filed with state agencies.
Why this matters
Fast growth across Central Texas has been pushing regional wastewater systems closer to their limits, and engineering and city materials frame the 40 MGD buildout as a way to lock in treatment capacity while sharpening filtration, nutrient removal and flood resilience. Plummer describes the upgrades and a staged construction approach that is intended to keep service disruptions in check as the work moves forward.
