ROBSTOWN, Tx — The Nueces County Water Control and Improvement District No. 3 has recorded a second positive arsenic test, and state regulators say a new violation is expected soon.
A Texas Commission on Environmental Quality spokesperson confirmed to KRIS 6 News that a sample collected January 29, 2026, came back at 0.0115 mg/L — above the federal limit of 0.01 mg/L, or 10 parts per billion.
TCEQ was notified of the result on February 13. The agency is now evaluating first-quarter 2026 compliance and "anticipates issuing a first-quarter 2026 MCL violation soon," according to a spokesperson.
This follows the district's first violation, issued January 23, 2026. As KRIS 6 News first reported, the district received a letter from TCEQ showing that fourth quarter 2025 testing — covering October through December — found arsenic at 13.1 parts per billion, roughly 31 percent above the EPA's maximum contaminant level. The district serves about 13,000 people in Robstown and North San Pedro.
General Manager Marcos Alaniz said at the time that elevated arsenic levels do not necessarily indicate an immediate health risk. "There's arsenic in a lot of things. It doesn't mean if there's arsenic in the water you're going to get sick," he told KRIS 6 News, noting the federal standard is based on long-term exposure. The district ordered private lab tests to confirm the readings. "We've got to get to the source. We've never had this issue before," Alaniz said.
As KRIS 6 News reported, officials pointed to drought conditions and low water levels in tributary creeks, wells and lakes as a contributing factor. Alaniz explained how drought concentrates contaminants in the water supply. "Being that they're at 9%, everything's coming to a small pond, right, so everything's concentrating in one little pool versus it being diluted out when it's full… it's gonna get worse as the ponds get smaller," he said.
Residents have also asked whether boiling their water would help. Alaniz said it would not.
"Boiling was not gonna help with, will not help with the arsenic," he said. "You know, arsenic is a heavy metal. We have to catch that before it gets into the plant. So boiling is not like bacteria, right? That's when you boil water, when you've got, bacteria in the water, low chlorine dosage that usually take care of that, we'll be put into a water boil notice when you detect bacteria in the water."
The district draws water from the Nueces River and Lake Corpus Christi, the same sources used by the City of Corpus Christi. Earlier this year, WCID signed an agreement with Corpus Christi to purchase three million gallons of treated water per day and receive reimbursement for a new connection totaling $1.7 million — signed the same day the first TCEQ violation letter was issued, though officials said the two events were unrelated.
Corpus Christi Water officials said their own tests near the city's eastern well outflow show arsenic levels remain well below EPA limits, though the river itself shows signs of stress. "We've already identified a number of high total dissolved solids streams entering the river — some as high as 10,000 TDS," said Nick Winkelman, interim COO of Corpus Christi Water, previously told KRIS 6 News.
A TCEQ spokesperson explained that under the Safe Drinking Water Act, public water systems that exceed health-based standards are required to provide public notice to consumers. The agency uses a third-party contractor to collect compliance samples, which are analyzed by an accredited laboratory before results are reported to TCEQ.
TCEQ also said residents can also monitor their water system's compliance status through TCEQ's Texas Drinking Water Viewer, a live database containing analytical results and compliance records for public water systems statewide.
