PFAS in Central Texas water, explained

PFAS shows up in the news a lot, usually as "forever chemicals," and it's a fair question to ask about your own tap. Here's the plain version: what they are, why the rules around them keep changing, what the actual testing shows for the cities we serve, and what removes them if you decide you want that.

What PFAS actually are

PFAS stands for per- and polyfluoroalkyl substances, a large family of manufactured chemicals used since the 1940s in things like nonstick cookware, waterproof fabric, food packaging, and firefighting foam. What makes them useful is also what makes them a long-term question: the chemical bond that holds them together barely breaks down in the environment, which is where "forever chemicals" comes from. They've turned up in water supplies across the country, not because any one source did something wrong, but because they were used so widely for so long.

Why the limits keep moving

The federal government has tightened its stance on PFAS in stages, as more research came in:

That's not regulators flip-flopping. It's the normal way environmental science works: better lab methods and more studies let regulators set a sharper number over time, and the number has consistently moved toward being more protective, not less.

As of this writing, the EPA has proposed adjusting the compliance timeline for that 2024 rule and reconsidering the limits on a few less-studied PFAS compounds.

What testing shows for our five cities

Every city we serve was required to test for PFAS under the EPA's Unregulated Contaminant Monitoring Rule (UCMR5) in 2023 through 2025. Here's the short version for each. Full numbers and sources are on each city's water quality page.

• Buda: No PFOA or PFOS detected. Two other compounds with no federal limit showed up in trace amounts.
• Kyle: No PFOA or PFOS detected. Three other compounds with no federal limit showed up in trace amounts.
• San Marcos: No PFOA or PFOS detected. One compound with a federal limit, PFHxS, came back well under it.
• New Braunfels: No PFOA or PFOS detected. Four other compounds showed up in trace amounts, all well under any applicable limit.
• Bastrop: Results depend on which system serves your address. The City of Bastrop and Aqua Water Supply Corporation both tested clean. Bastrop County WCID 2, which serves Tahitian Village, hasn't published results we could find.

None of the compounds that turned up anywhere are PFOA or PFOS, the two studied longest and regulated most tightly. What did turn up were shorter-chain compounds at single-digit-to-teens parts per trillion, most without a federal limit at all yet.

A word on what "not detected" actually means. EPA's UCMR5 testing measures down to a few parts per trillion, not down to zero, so a non-detect result means a compound wasn't found above that threshold, not that it's proven completely absent. The testing also covers a specific list, the 29 PFAS compounds (plus lithium) that EPA required systems to check for, not every PFAS compound that exists. And every result is a snapshot of one testing window, not a permanent condition. Water systems shift with the seasons and with growth, and a few of our own cities already have new sources coming online that will change what's in the blend.

That's part of why we check this data every year instead of treating one round of testing as the final word, and it's a fair part of why some families choose extra filtering even when today's results come back clean.

What actually removes PFAS

If you want to reduce PFAS beyond what your city already tests clean for, two technologies have real evidence behind them: reverse osmosis and specific carbon filtration built for PFAS. Not every carbon filter does this. The honest way to know if a system actually reduces PFAS is a certification against NSF/ANSI standards (53, 58, or P473 are the ones that cover PFAS specifically), not a marketing claim on the box. If a filter doesn't carry one of those certifications, its PFAS performance is a guess.

We install reverse osmosis systems, and we're glad to talk through what a certified PFAS-reduction option would look like for your home once we're serving the area.

Where that leaves you

Nobody can promise that trace amounts below today's limits are completely harmless. The science on PFAS is still being written, and it will probably keep moving for years. That's a fair reason to want extra filtering even where your water tests clean on every current measure, and it's an equally fair reason not to. Either choice is reasonable. If you want to talk through the honest tradeoffs for your own home, the free water test is a good place to start.