Water quality in question From the cover
How it works
The background
odors, Nowlin said. While he can’t identify the specific kind of algae in the South Fork San Gabriel River—nuisance, mutant or harmful—Nowlin said algal mats he’s seen from photos are “not good.” When Georgetown’s Garey Park first opened on the other side of Bunnell’s property, he said he became concerned about the health of people in the water. “There were kids coming down, playing in the river, so I got very concerned that someone was going to get very sick,” Bunnell said.
Phosphorus is an essential element needed for all life and is usually prominent in fertilizers, said Weston Nowlin, a biology professor at Texas State University. Phosphorus alone isn’t necessarily harmful, he said. However, water with high levels of phosphorus and nitrogen usually leads to algae and bacterial growth, along with lower water quality. Someone swimming in that water runs a higher risk of getting sick, Nowlin said. The growth and decay of algae also produces
The South Fork Wastewater Treatment Plant’s recent issues date back to 2018 when the TCEQ found several violations with the facility. “As the [city] grows, it remains committed to environmentally responsible, scientifically sound solutions for wastewater management that meet TCEQ standards,” a statement from the city reads. After pending for six years, the TCEQ issued the South Fork WWTP’s permit renewal in April, which allows it to increase its effluent from 2 million to 4 million gallons per day. The South Fork WWTP’s discharge was exceeding TCEQ’s limits for dissolved solids, chloride and sulfate, David Thomison, Liberty Hill director of public works, said at a Sept. 11 City Council meeting. Thomison said the plant wasn’t designed to meet the low levels set by the TCEQ. The average phosphorus levels in Liberty Hill’s effluent from December 2022- April 2023 was between 0.05-0.08 milligrams per liter, per TCEQ documents. Per TCEQ, Liberty Hill is required to conduct a total dissolved solids, chloride and sulfate source work plan study, which costs $185,287. The TCEQ approved the plan, in which the city partners with Garver Engineering, a firm that will prepare annual progress reports in December. Liberty Hill still needs to submit a separate phosphorus work plan study.
Wastewater treatment process 2 Water from residential and business drains collects in the sewer, where it’s transported to a nearby 1
3
Inorganic material in the wastewater is removed and hauled away, while the rest is treated, filtered and disinfected.
Some of the treated effluent is recycled and used for cleaning the plant, but the remainder is discharged into waterways. The South Fork WWTP discharges into the San Gabriel River.
lift station and then to the wastewater treatment plant.
SOURCE: CITY OF LIBERTY HILL/COMMUNITY IMPACT
Current situation
Phosphorus effluent limits
Within the city’s 2018 permit renewal application for the South Fork WWTP was a request to double the facility’s effluent discharge. The TCEQ approved this increase in April, with the caveat that the city must complete a 36-month study into improving the plant and lower the phosphorus levels further. “You’re causing even more—probably—water quality problems if you’re increasing the total volume of your discharge but keeping the effluent concentration the same,” Nowlin said. The city plans to build two more wastewater plants in north and west Liberty Hill, and the South Fork WWTP has experienced expansion delays. Residents inquired about Liberty Hill’s proposed north WWTP in the Saddleback community at a Dec. 3 TCEQ public meeting. Construction details are pending, said Vince Perkins, Liberty Hill safety and compliance environmental coordinator. The effluent would discharge into the North Fork San Gabriel River, which flows into Lake George- town—a public drinking water source. According to the draft permit, the plant’s final phase phosphorus effluent limitations will be 25 times greater than the South Fork WWTP’s. A TCEQ official said these limits were designed specifically for the uses of the North Fork San Gabriel River.
0.6
Final phase
Charting the waters
0.4
April 2024: The TCEQ approves the 2018 permit renewal request and orders the city to reduce phosphorus levels from 0.15 milligrams per liter to 0.02 mg/L June 2020: Pending corrective action, Liberty Hill is fined about $100,000 for eight violations May 2018: TCEQ begins an investigation into the South Fork WWTP Sept. 2018: TCEQ receives Liberty Hill’s request to renew its wastewater permit and increase effluent limits May 2024: Liberty Hill submits a motion for rehearing, calls effluent limit “technically impossible”
0.2
Prior
New
0
Proposed north WWTP
South Fork WWTP
SOURCE: TEXAS COMMISSION ON ENVIRONMENTAL QUALITY/COMMUNITY IMPACT
258
Proposed north WWTP
183
29
RONALD REAGAN BLVD.
266
SOURCES: CITY OF LIBERTY HILL, TEXAS COMMISSION ON ENVIRONMENTAL QUALITY/COMMUNITY IMPACT
SOUTH FORK SAN GABRIEL RIVER
South Fork WWTP
N
24
COMMUNITYIMPACT.COM
Powered by FlippingBook