CheckPFAS

City overview · Hays County

PFAS in San Marcos, TX

Low Level

EPA UCMR 5 tested 4 public water systems serving the San Marcos area across 2 ZIP codes. Only trace PFAS were detected across San Marcos's tested systems.

Water systems tested
4
Systems above EPA limits
0
ZIP codes covered
2
County
Hays County, Texas

Plain English

01What this means for San Marcos

The water systems serving the San Marcos area measured only low, trace concentrations of PFAS — well below the EPA's Maximum Contaminant Levels. For most residents this represents minimal risk from drinking water. Review your specific ZIP below, and check your utility's annual Consumer Confidence Report for year-over-year trends.

By utility

02Water systems serving San Marcos

  1. CITY OF SAN MARCOS

    4 detected · 0 above limit · PWSID TX1050001

    Low Level

  2. MAXWELL WSC

    3 detected · 0 above limit · PWSID TX0280003

    Low Level

  3. CRYSTAL CLEAR SUD

    2 detected · 0 above limit · PWSID TX0940015

    Low Level

  4. TEXAS STATE UNIVERSITY - SAN MARCOS

    1 detected · 0 above limit · PWSID TX1050003

    Low Level

By ZIP code

03Find your exact result

Contamination can differ block to block. Select your ZIP code for the precise reading at the utility that serves your address.

7866678667

Source & Methodology

About this data

Source
EPA UCMR 5
Sampling period
January 2023 – December 2025
Aggregation
4 utilities across 2 ZIP codes
Detection threshold (MRL)
~1.5–2 ppt

City-level figures aggregate the individual public water systems tested under EPA UCMR 5 whose service area falls within the San Marcos area. Values reflect water quality at the treatment plant; your home's plumbing can affect what reaches your tap. Select your ZIP above for the utility-specific reading.