Public water system · TX2460139

Active

Vista Oaks MUD

At a glance

Vista Oaks MUD (PWSID TX2460139) is an active community water system in Williamson County, Texas. It reports serving 2,724 people through 909 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 10 violations for this system; 1 is health-based, and the most recent began in October 2011.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

2,724

Service connections

909

Primary source

SWP

Purchased surface water

System type

CWS

Community water system

System record

PWSIDTX2460139

System typeCommunity water system

Activity statusActive

Population served2,724

Service connections909

Primary water sourcePurchased surface water

Owner typeLocal government

Primacy agencyTX state drinking water program

City served—

StateTexas

ZIP—

CountyWilliamson County

How does Vista Oaks MUD compare with other water systems in Williamson County?

By EPA's size categories, Vista Oaks MUD is a small system (501 to 3,300 people). Williamson County has 51 active public water systems. Its population served is well below the county average of 13,777 people per system, and accounts for 0.4% of the 702,636 people reported by systems filed under the county. Across Texas, the 7,078 active systems average 4,789 people each. Nationally, the average active community water system reports serving 6,703 people, so Vista Oaks MUD is about 59% below that figure.

What does “community water system” mean?

A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Texas has 4,594 active community water systems, 65% of the state's 7,078 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 1,192 Texas systems (17%) list purchased surface water as their primary source.

Who owns and regulates Vista Oaks MUD?

EPA lists Vista Oaks MUD as owned by a local government. The TX state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 33 of the 51 active systems in Williamson County (65%) are also owned by a local government.

Does Vista Oaks MUD have drinking water violations?

EPA's records list 10 violations for this system; 1 is health-based, and the most recent began in October 2011. The violations listed here began between August 1993 and October 2011. By type: 5 public notice, recordkeeping or other, 4 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (6 of them). EPA lists 8 as resolved and 2 as archived. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.

Began	Violation	Contaminant or rule	Health-based	Status
2011-10-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
2011-10-01	Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75	Public Noticecode 7500	No	Resolved
2007-01-01	Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75	Public Noticecode 7500	No	Resolved
2006-09-01	Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24	Total coliform bacteria (TCR)code 3100	No	Resolved
2006-01-01	Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75	Public Noticecode 7500	No	Resolved
2005-09-01	Monitoring and reportingMonitoring, Routine Major (TCR) · code 23	Total coliform bacteria (TCR)code 3100	No	Resolved
2003-09-01	Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75	Public Noticecode 7500	No	Resolved
2003-05-01	Monitoring and reportingMonitoring, Routine Major (TCR) · code 23	Total coliform bacteria (TCR)code 3100	No	Resolved
1993-08-01	Public notice, recordkeeping or otherNotification, Public · code 06	Total coliform bacteria (TCR)code 3100	No	Archived
1993-08-01	Monitoring and reportingMonitoring, Routine Major (TCR) · code 23	Total coliform bacteria (TCR)code 3100	No	Archived

All 10 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.

Vista Oaks MUD: frequently asked questions

Who runs Vista Oaks MUD?

Vista Oaks MUD (PWSID TX2460139) is a community water system owned by a local government. It is regulated by the TX state drinking water program.

How many people does Vista Oaks MUD serve?

Vista Oaks MUD reports serving 2,724 people through 909 service connections in Williamson County, Texas.

Where does Vista Oaks MUD get its water?

EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.

Does Vista Oaks MUD have any drinking water violations?

EPA's records list 10 violations for this system; 1 is health-based, and the most recent began in October 2011. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.

Is Vista Oaks MUD's water safe to drink?

AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 10 violations for this system; 1 is health-based, and the most recent began in October 2011. For current results, consult the system's annual water quality report, EPA ECHO, or the TX state drinking water program.

Where can I find Vista Oaks MUD's water quality report?

As a community water system, Vista Oaks MUD must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.

Other water systems in Williamson County

Water system	County	Population served	Type	Source
City of Georgetown	Williamson	191,639	Community	Surface water
City of Round Rock	Williamson	130,662	Community	Surface water
City of Leander	Williamson	98,330	Community	Surface water
City of Cedar Park	Williamson	86,939	Community	Surface water
Jonah Water Sud	Williamson	29,861	Community	Purchased surface water
City of Hutto	Williamson	29,580	Community	Purchased surface water

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About this data

Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.

Cite as: AquaCensus, “Vista Oaks MUD, PWSID TX2460139, Texas”, https://aquacensus.com/water-systems/texas/vista-oaks-mud-tx2460139 (data as of October 1, 2026).