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Drinking water / Texas

Gbra Calhoun County Rural Water System

PWSID TX0290007 - Cypress

PFAS was measured above a final federal limit in this system.

The highest result was 6:2 FTS at 51 ng/L, against a federal limit of - ng/L. A system over the limit has a legal obligation to act by 2031; it does not mean the water is unsafe to drink today, and it does not describe what reaches one specific tap.

4,482

people served

1,494

service connections

purchased surface water

primary source

240

sample results

Every compound detected

Highest single result per compound, in nanograms per litre (the same unit as parts per trillion). EPA proposed in May 2026 to rescind the limits marked as withdrawn, so those results are reported without a comparison.

CompoundHighest resultFederal limitReading
6:2 FTS51 ng/Lnonebelow limit
PFPeA13.9 ng/Lnonebelow limit
PFBA7.7 ng/Lnonebelow limit
PFHxA7.2 ng/Lnonebelow limit
PFBS5.4 ng/Lnonebelow limit
PFOS5 ng/L4 ng/Labove limit
PFOA4.8 ng/L4 ng/Labove limit
PFHxS4.7 ng/Lwithdrawnno current limit

Counties served

What this does not tell you

These are entry-point results for the system, not one tap. Water mixes between sources, sits in mains and passes through household plumbing. A certified lab test of your own tap is the only thing that answers what you drink, and it is the only route at all for a private well.

How to test your tap water

If you want to treat it

Reverse osmosis and properly specified activated carbon remove most PFAS at the tap. Certification to NSF/ANSI 53 or 58 with an explicit PFOA and PFOS claim is what separates a PFAS filter from a taste filter.

Which filters actually work

Source: EPA Fifth Unregulated Contaminant Monitoring Rule occurrence data, with system detail from EPA SDWIS. Umwelt reports these results as published. Methodology and sources