This does not impact the city's source of drinking water, but the city may issue guidance for the public use of Brushy Creek following testing for suspended solids and E. coli done by the Texas Commission on Environmental Quality.
“We are working diligently to reach a resolution to this matter, and our top priority right now is finding the exact location of where groundwater or surface water may be entering the system,” Utilities Director Michael Thane said in the announcement. “Our wastewater treatment plant operators have decades of experience working in treatment plants, and they are working around the clock through numerous challenges to reduce our impact on Brushy Creek.”
Increased flow of water, according to a release, may be the result of ground and surface water inadvertently entering the waste water system. Such increases were noted sporadically by city water operations beginning in May 2021, a city report states. Organic solids, also referred to as "total suspended solids," were passed through the plant's clarifiers to Brushy Creek during peak hours. The creek has since been inspected daily by city staff, and TCEQ officials have visited the plant on multiple occasions to confirm its compliance. The plant had been so up until the last week, when intake levels dramatically increased.
Recent increases in intake have pushed the average over the past week to between 22 million and 24 million gallons per day, or MGD, with peak flows between 32 and 33 MGD. In May 2021, the approximate average was between 18 and 19 MGD, the city said.
To mitigate the effects of the increased wastewater flow, the city will bring an older water treatment plant online to divert 1.7 MGD from the main regional plant to "enhance treatment capacity" and will inspect the underground regional wastewater infrastructure to find the source of additional inflow with a specialized camera. It will also work with partner cities to carry out inspections of each of their wastewater collection systems.
While it is unclear what the cost for the fix will be, the city has authorized a $42,000 emergency contract for a third-party company to inspect wastewater line segments along Hairy Man Road and Brushy Creek Road as this segment showed discrepancies in testing, possibly a sign of "significant water infiltration," according to the city.
An update on the situation is expected to be given by Thane at the March 8 Round Rock City Council packet briefing, and this story will be updated with additional information as it becomes available.
