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Williamson County, Texas: drinking water records

Explore EPA records for 40 community water systems across 19 ZIP codes in Williamson County, then find water-testing resources and available recent monitoring-station readings.

In focus40Community water systems
Public records. Clearer context.

Data as of EPA UCMR 5 final release, August 2026 (file dated Aug 28, 2026) · EPA SDWIS 2026Q2 (file dated Jul 9, 2026). How we build these pages

Drinking-water records

EPA survey and compliance records are historical reports. UCMR 5 results are available for 17 of the 40 listed systems in this snapshot. A system with no reported PFAS detection is not a test of every tap or every contaminant.

17
systems in EPA's PFAS survey
14
systems where PFAS was found
0
systems at or above the PFOA or PFOS limit, on the yearly-average basis EPA uses
0
systems that have reached the lead action level
8
systems with a health-based violation since 2016

System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.

Water systems in this county

All 40 active community systems in the available county records, sorted by record completeness. Scroll the table to explore more systems.

Water systemPeople servedPFAS survey resultsPFAS foundHealth-based violationsLead, 9 in 10 homes at or below
City of Georgetown TX2460001191,639660712.2 ppb
Jonah Water SUD TX246002229,861480722.5 ppb
Sonterra MUD TX246015716,614180420.4 ppb
City of Bartlett TX24600062,95060052.7 ppb
City of Round Rock TX2460003130,662300405.1 ppb
City of Leander TX246001298,330240101.1 ppb
City of Cedar Park TX246000986,939240104.0 ppb
City of Hutto TX246000729,580240000 ppb
City of Taylor TX246000420,622120501.9 ppb
Brushy Creek MUD TX246006118,314120501.3 ppb
Jarrell Schwertner WSC TX24600119,681660200 ppb
City of Liberty Hill TX24600138,7770042.1 ppb
Williamson County Wsid 3 TX24601528,26560300.5 ppb
Block House MUD TX24601106,61895100.8 ppb
Williamson Travis County MUD 1 TX24601205,793120002.0 ppb
Fern Bluff MUD TX24601285,682120200 ppb
Williamson County MUD 11 TX24601594,248120205.0 ppb
Williamson County MUD 10 TX24601453,513120301.3 ppb
Blessing Mobile Home Park TX24600311,5180013.6 ppb
City of Florence TX24600051,1360052.2 ppb
City of Thrall TX24600159750021.3 ppb
City of Jarrell TX24601693,4500001.5 ppb
Paloma Lake MUD 1 TX24601643,1110000 ppb
Vista Oaks MUD TX24601392,7240002.3 ppb
Paloma Lake MUD 2 TX24601652,2650001.8 ppb
City of Granger TX24600021,9140004.0 ppb
Durham Park WSC TX24600381,2510003.4 ppb
Tal Tex TX24600649390000 ppb
San Gabriel River Ranches TX24600468910000 ppb
Walsh Ranch MUD TX24601607140001.2 ppb
Brushy Bend Park TX24600506450003.6 ppb
South San Gabriel Ranches TX24600265100003.7 ppb
Sunny Creek MHC TX24601445100000 ppb
High Gabriel WSC TX24600274920000 ppb
Round Rock Ranch PUD Utility Company TX24601612850000.6 ppb
Liberty Greenline TX2460162460000 ppb
County Cottage Lines TX246017829000not reported
Brazos River Authority Granger Lake Regi TX24601550000not reported
Brushy Creek Regional Utility Authority TX24601660000not reported
Lone Star Rwa TX24601720000not reported

USGS · Monitoring stations

The water, more recently.

Available station readings in Williamson County, Texas. Each measurement keeps its time, unit and original source.

These readings describe water at a monitoring station. They do not test your tap, measure PFAS or lead, or determine whether water is safe to drink or swim in.

Recent observations load when this section comes into view.

Station coverage and available measurements vary by county.

Explore USGS Water Data
How these readings update

We check for updates every 10 minutes while this section is visible and show supported observations from the last 48 hours. The time beside a reading is when USGS measured it; the checked time is when our service retrieved the response. We mark a reading more than 6 hours old as older. Provisional observations can change after USGS review. A missing reading does not mean zero or clean water.

Temperature, pH, dissolved oxygen, turbidity, conductivity, streamflow and water level are shown only where a station reports them. Different measurements have different units and sampling intervals. USGS data and documentation.

Your next step

Water testing, reports & local help.

Use these official directories to find your drinking-water agency, a certified laboratory and public water records. We have not yet added an individually reviewed local resource list for this county.

Official national directories

Water testing

Find your state’s private-well program

EPA’s state directory points well owners to local program information. Services and eligibility vary by state and county.

U.S. Environmental Protection Agency
Source reviewed · Source updated

Water testing

Find a certified drinking-water laboratory

Use EPA’s directory to reach your state’s laboratory certification program. EPA does not provide on-request testing of residential drinking water.

U.S. Environmental Protection Agency
Source reviewed · Source updated

Public records

Find your utility’s Consumer Confidence Report

EPA links to community water-system reports and explains how to read them. Look for your actual supplier rather than assuming every address in a county shares one system.

U.S. Environmental Protection Agency
Source reviewed · Source updated

Public records

Explore USGS water observations

Find current and historical observations from USGS monitoring locations, including available stream, lake, and groundwater data. Measurements vary by station and do not replace a test of your household water.

U.S. Geological Survey
Source reviewed

A county overview cannot identify every property’s water provider. If you use a public water system, confirm its name on your bill and request its annual Consumer Confidence Report. Private wells need their own testing; public-system records do not describe a private well.

Understand water testing and laboratory reports

Resource descriptions are compiled by Tap Water Lookup. Review dates describe our source check, not a new water sample. How we review sources · Suggest a correction

Explore your area

Local coverage in Williamson County

19ZIP areas in this overview

Explore the water-system records, recent station readings and testing resources on this county page. They describe the systems and stations identified in each section; they are not a separate water test for every community.

Towns and communities

  • Austin
  • Cedar Park
  • Coupland
  • Florence
  • Georgetown
  • Granger
  • Hutto
  • Jarrell
  • Liberty Hill
  • Round Rock
  • Taylor
  • Thrall
  • Weir
Explore water-system recordsFind water-testing resources
View ZIP areas and understand coverage
  • 76527Florence
  • 76530Granger
  • 76537Jarrell
  • 76573
  • 76574Taylor
  • 76578Thrall
  • 78613Cedar Park
  • 78615Coupland
  • 78626Georgetown
  • 78628Georgetown
  • 78633Georgetown
  • 78634Hutto
  • 78642Liberty Hill
  • 78664Round Rock
  • 78665Round Rock
  • 78674Weir
  • 78681Round Rock
  • 78717Austin
  • 78729Austin

These Census ZIP Code Tabulation Areas are grouped here by their largest county overlap. A ZIP area can cross county lines and contain several water suppliers or private wells. Place labels reflect Census geography, not verified postal city names or utility service boundaries.

Records for these areas are currently presented in this county overview rather than individual ZIP reports. An unpublished report does not mean there are no water records. Confirm your supplier on your water bill; if you use a private well, testing your own well is the relevant next step.

Beyond this county page

Keep reading. Compare nearby.

PFASChoosing a PFAS filterPFAS was found in 14 of the 17 systems EPA surveyed here. See how to check a filter’s certified PFAS reduction.LeadLead in drinking waterHow EPA’s lead records work and what the action level means for a water system.Your utilityFind your annual water reportConfirm the supplier on your bill, then read its Consumer Confidence Report for local results.

Counties near Williamson County

All Texas counties

Sources and scope

EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Database prepared 2026-09-03.

Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.

Compiled by Tap Water Lookup from the sources identified on this page. Read the methodology and review process.

Keep exploring

Every record tells
part of the story.

Find a place. Read the measurements.
Understand the context.

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