'Forever chemicals' were found in the Inner Harbor. What does that mean for desalination?
by Kirsten Crow
Corpus Christi Caller Times
July 13, 2025
A report commissioned by private entities revealed the presence of PFAS, also known as "forever chemicals," in the Corpus Christi Inner Harbor, the proposed source of water for a desalination plant.
Environmental groups are urging the city to conduct a comprehensive study on PFAS contamination and postpone further construction on the desalination plant until a plan is developed to address the issue.
City officials say they were already aware of the potential presence of PFAS and have incorporated treatment processes into the plant's design.
Debate continues regarding the effectiveness of reverse osmosis in removing PFAS from seawater and the potential risks of concentrated PFAS in the plant's discharge.
Questions are being raised on how the city of Corpus Christi’s proposed desalination plant will manage a class of emerging contaminants — those nicknamed “forever chemicals” — following the release of findings in a privately commissioned report that suggests concerning levels measured in the ship channel.
In a six-page memo summarizing the report’s findings, leaders of nearly a dozen environmental advocacy groups assert that data shown in a consultant’s documents indicate the presence of per- and polyfluoroalkyl substances in the Inner Harbor Ship Channel, the source of water that would be processed by the plant for consumption, as well as the point where discharge would be directed.
Specific types of the chemical compounds, also known as PFAS, have been linked to serious health issues, according to research by federal agencies.
Initially forwarded to local officials on June 26, the groups assert in the memo that the study’s findings should prompt the city to “immediately authorize a comprehensive study of PFAS contamination in the Inner Harbor, Corpus Christi Bay, and Nueces Bay.”
Data indicating the presence of PFAS in the Inner Harbor wasn’t surprising, said Drew Molly, chief operating officer of Corpus Christi Water. Officials have been aware of the likelihood that they may be present in the Inner Harbor and had already been considering how to manage it, he added.
Concerns about PFAS are being researched and addressed, city officials wrote in a June 30 email to the Caller-Times, stating that “PFAS and other micro-contaminants have always been considered in the approach for designing the Inner Harbor Water Treatment Campus.”
PFAS sampling will be performed during a demonstration of the pilot plant, Molly wrote in the June 30 email, describing it as “the best way to monitor and validate raw water PFAS levels and removal efficiencies of the pretreatment and reverse osmosis processes.”
The pilot plant essentially acts as a test run — building and operating a smaller plant in preparation of constructing and operating the full-scale plant, planned to generate as much as 30 million gallons of treated water per day.
It is currently in development, Molly told the Caller-Times.
The city and its desalination plant consultant see “no cause for concern about this report,” Molly wrote.
“The City is confident that the proven treatment technology will address all contaminants and that the new facility will provide safe, reliable drinking water,” he added.
In the memo, the groups urge the city to consider developing “a comprehensive risk assessment and a responsive operational plan to ensure that the Inner Harbor desalination facility will protect public health and comply with federal regulations.”
The groups are also calling on officials to postpone further engineering or construction work on the project “pending results of the PFAS study and development of an operational plan.”
“The presence of any amount of PFAS in the Inner Harbor is unquestionably of serious concern from a public health perspective given the City’s plan to build a desalination facility that would treat water from, and discharge effluent into, that body,” the memo states.
What are PFAS?
PFAS, as a class, represent thousands of chemical compounds, with some compositions potentially linked to higher health risks than others, studies have shown.
Some levels of certain compounds have been associated with certain types of cancers, as well as immune deficiencies, among other afflictions, according to the U.S. Environmental Protection Agency.
PFAS can be found in a wide spread of consumer products, present in everything from closets to the kitchen — to include certain kinds of water-repelling fabric and popular nonstick cookware to fire-suppressing foam and waxy food packaging, according to experts.
They also can exist nearly everywhere, including water and wastewater.
PFAS are stubborn and are not eliminated over time. Instead, they collect where they have been deposited, including the bodies of people and animals, according to health and science experts.
It’s nearly universally accepted that there remain many unknowns related to PFAS. Currently, there is no all-inclusive inventory of the compounds that may be harmful.
Regulations of certain kinds of PFAS in the drinking water lie ahead. Compliance monitoring is set to begin in 2027, with enforcement on the maximum contaminant levels anticipated in 2031, according to the Texas Commission on Environmental Quality’s website.
The maximum amount of specific PFAS in drinking water — perfluorooctane sulfonate, known also as PFOS, and perfluorooctanoic acid, or PFOA — is expected to be set at 4 parts per trillion, it states.
A “maximum contaminant level goal” — which is not enforceable — for the substance is zero parts per trillion, the group’s memo states — indicating that “the EPA’s position has been and currently remains that the only truly safe amount of PFOS or PFOA in drinking water is none.”
While there are regulations coming into place for drinking water, there are currently no adopted guidelines for wastewater, according to the memo and Molly.
Rules for PFAS content in wastewater may be coming down the pipeline in upcoming years, several officials have said.
The findings
The memo sent to city officials by the groups — among them, the Texas Campaign for the Environment and the local chapter of the Sierra Club — was based on an analysis conducted by William “Jim” Rogers.
Rogers, a professor of environmental science at West Texas A&M University, performed the analysis as a private consultant.
The report showed that all eight surface water samples taken in November 2024 detected PFAS. One sample measured PFOS “in excess of the allowed concentration in drinking water set by the Biden Administration just last year, and reaffirmed by the Trump Administration just last month,” the memo states.
The samples were taken at four locations, Rogers told the Caller-Times. At each site, one sample was collected for the surface water and one sample was collected at a 1-foot depth.
Of the readings, one showed PFOS compound at 5.5 parts per trillion, with “the remaining PFOS levels ranging from 2.4 ppt to 3.2 ppt, for an average reading across all eight samples of 2.8 ppt,” according to the groups’ memo.
PFAS removal has already been “considered in the treatment approach and costs,” Molly wrote in his July 9 email to the Caller-Times.
In this case, that’s reverse osmosis.
“Reverse osmosis (RO) membranes for seawater have higher removal rates than RO membranes for lower salinity feedwaters or freshwater for the smallest ions (like sodium and chloride),” Molly wrote. “We expect even better removal rates for PFAS, too.”
While reverse osmosis is shown effective for municipal drinking, there’s not a clear answer on how it would perform with seawater, the groups state in the memo, contending that the high total dissolved solids content from seawater could “have a negative impact on the PFOS removal.”
“As far as we’ve determined, there is simply no available data indicating exactly what the nature or scope of that impact could be, leaving also unknown what steps could be required to achieve consistent PFOS removal, and at what cost to Corpus Christi ratepayers,” the memo states.
The study
The study was funded by owners of a brackish groundwater project that had proposed to sell water to the city, according to the memo. The groups are not affiliated with that project, it states.
The Eshleman-Vogt brackish groundwater proposal is not why the study was commissioned, project co-owner Darrell Brownlow told the Caller-Times on July 1 — there were concerns about the potential for PFAS in the Inner Harbor water.
The findings, Brownlow said, were “a little bit shocking.”
The documents were released to environmental groups after the city didn’t act on the information when it was shared, he added.
“Whether we ever sell a drop of water to the city of Corpus from the (groundwater) project or not, it’s kind of not the point,” Brownlow said. “The point is we’ve got a problem … with PFAS in the Inner Harbor.”
The Eshleman-Vogt brackish groundwater project remains under evaluation and consideration, Molly said, and it’s expected that a report will be delivered to the City Council.
The findings of the analysis don’t warrant postponing work on the desalination plant — particularly in light of the city’s dependence on surface water sources — and concerns about reverse osmosis are “largely speculative,” according to an engineer unaffiliated with Corpus Christi’s desalination project.
A “cancellation or indefinite delay of a project of this scale—based solely on eight water samples collected during a single month, with an average PFAS concentration of 2.8 parts per trillion (ppt)—feels premature,” wrote Mark Boyd, a Dallas-based environmental engineer, in a message to the Caller-Times July 9.
“We don’t know whether those results reflect a broader condition, a one-time spill, or another isolated event,” he added. “It's also possible the samples were influenced by a specific incident and may not accurately characterize general harbor water quality. Further sampling and data review are clearly warranted before using harbor PFAS levels as a basis for opposition.”
The results
The idea of distributing the information on the PFAS analysis was not to present it as a comprehensive analysis but instead to highlight the concern about PFAS, as well as the city’s need to perform more extensive study, several advocates said.
In the memo, the groups state that although city officials had viewed the PFAS study several months ago, “city management appears to have charged ahead with plans to construct the desal facility without any public acknowledgement of the possible health risk or its implications for the project.”
The information was provided to a city consultant for review when it was received, Molly told the Caller-Times, but there were questions about the data — for example, how it was collected.
“We don’t know a lot about … why this was done,” he said. “We just know that it showed up at our doorstep. When we get these kinds of data or information, we look at it. We take all of it seriously.”
The work met quality control, Rogers said, describing the data as “rock solid.”
The discharge
In the memo, the groups also expressed concerns about brine discharge into the Inner Harbor, suggesting that the process could potentially concentrate PFAS and pose increased risk to the marine life that inhabits the bay.
Discharging “concentrated PFOS into waters populated by Redfish, Speckled Trout, Flounder and other gamefish ultimately caught in the Bay and consumed by local and visiting anglers and their families would amount to a shocking disregard for the EPA’s recommendations and the known risks of bioaccumulation,” the memo states.
In emails, Molly stated that there are plans for multiple monitoring stations near the discharge points, which “will include the collection of water quality samples four times per year and will include testing of aquatic species.”
Although a percentage of PFAS would be in the discharge, “the PFAS concentration will be reduced due to removal from some of the treatment processes,” he wrote.
Should regulations come into place for wastewater, the plant as planned “could easily be out of compliance or subject to enforcement” in the future, according to the memo.
Officials will “remain alert to any possible changes to regulations and can engineer solutions to meet or exceed future requirements,” according to a post on the city’s site.
Managing “brine discharge is a recognized challenge in desalination,” Boyd, the Dallas-based engineer, wrote in his email, but he added that “startup testing will further assess RO performance and brine discharge impacts.”
“If those tests indicate a concern, they can trigger appropriate design modifications or operational changes,” he wrote.
