Public water system · TX0660003
ActiveSan Diego MUD 1
At a glance
San Diego MUD 1 (PWSID TX0660003) is an active community water system in Duval County, Texas. It reports serving 6,291 people through 2,658 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in April 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
6,291
Service connections
2,658
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does San Diego MUD 1 compare with other water systems in Duval County?
By EPA's size categories, San Diego MUD 1 is a medium system (3,301 to 10,000 people). Duval County has 9 active public water systems, and San Diego MUD 1 is the largest of them by population served. Its population served is about 4.5 times the county average of 1,392 people per system, and accounts for 50% of the 12,532 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 San Diego MUD 1 is roughly in line with 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. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 5,215 Texas systems (74%) list groundwater as their primary source.
Who owns and regulates San Diego MUD 1?
EPA lists San Diego MUD 1 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. 7 of the 9 active systems in Duval County (78%) are also owned by a local government.
Does San Diego MUD 1 have drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in April 2026. The violations listed here began between July 2018 and April 2026. By type: 5 public notice, recordkeeping or other, 4 contaminant level above the legal limit, 1 required treatment not met, 1 reporting and 1 monitoring. The contaminant or rule involved most often is Arsenic (4 of them). EPA lists 7 as resolved and 5 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2026-04-02 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Unaddressed |
| 2025-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Unaddressed |
| 2025-06-30 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Unaddressed |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2024-04-15 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2024-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2024-02-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2024-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2023-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2018-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
The 12 most recent 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.
San Diego MUD 1: frequently asked questions
Who runs San Diego MUD 1?
San Diego MUD 1 (PWSID TX0660003) is a community water system owned by a local government. It is regulated by the TX state drinking water program.
How many people does San Diego MUD 1 serve?
San Diego MUD 1 reports serving 6,291 people through 2,658 service connections in Duval County, Texas.
Where does San Diego MUD 1 get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does San Diego MUD 1 have any drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in April 2026. 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 San Diego MUD 1'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. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in April 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the TX state drinking water program.
Where can I find San Diego MUD 1's water quality report?
As a community water system, San Diego MUD 1 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 Duval County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Freer Wcid | Duval | 2,923 | Community | Groundwater |
| Duval County Crd Benavides | Duval | 2,285 | Community | Groundwater |
| City of San Diego Glossbrenner Unit | Duval | 545 | Community | Purchased groundwater |
| Duval County Crd Realitos | Duval | 200 | Community | Groundwater |
| Duval County Crd Concepcion | Duval | 160 | Community | Groundwater |
| Us Border Patrol Station Freer | Duval | 50 | Transient non-community | Groundwater |
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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, “San Diego MUD 1, PWSID TX0660003, Texas”, https://aquacensus.com/water-systems/texas/san-diego-mud-1-tx0660003 (data as of October 1, 2026).