Public water system · TX1011746
ActiveNorthwest Harris County MUD 23
At a glance
Northwest Harris County MUD 23 (PWSID TX1011746) is an active community water system in Harris County, Texas. It reports serving 4,470 people through 1,490 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in January 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
4,470
Service connections
1,490
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Northwest Harris County MUD 23 compare with other water systems in Harris County?
By EPA's size categories, Northwest Harris County MUD 23 is a medium system (3,301 to 10,000 people). Harris County has 1,246 active public water systems. Its population served is roughly in line with the county average of 4,849 people per system, and accounts for less than 0.1% of the 6,041,784 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 Northwest Harris County MUD 23 is about 33% 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. 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 Northwest Harris County MUD 23?
EPA lists Northwest Harris County MUD 23 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. 508 of the 1,246 active systems in Harris County (41%) are also owned by a local government.
Does Northwest Harris County MUD 23 have drinking water violations?
EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in January 2023. The violations listed here began between September 2006 and January 2023. By type: 2 monitoring, 2 monitoring and reporting, 1 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 6 as resolved. 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2023-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2011-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2008-12-18 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2008-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2006-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 6 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.
Northwest Harris County MUD 23: frequently asked questions
Who runs Northwest Harris County MUD 23?
Northwest Harris County MUD 23 (PWSID TX1011746) is a community water system owned by a local government. It is regulated by the TX state drinking water program.
How many people does Northwest Harris County MUD 23 serve?
Northwest Harris County MUD 23 reports serving 4,470 people through 1,490 service connections in Harris County, Texas.
Where does Northwest Harris County MUD 23 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 Northwest Harris County MUD 23 have any drinking water violations?
EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in January 2023. 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 Northwest Harris County MUD 23'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 6 violations for this system; 1 is health-based, and the most recent began in January 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the TX state drinking water program.
Where can I find Northwest Harris County MUD 23's water quality report?
As a community water system, Northwest Harris County MUD 23 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 Harris County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Houston | Harris | 2,970,543 | Community | Surface water |
| City of Pasadena | Harris | 152,000 | Community | Purchased surface water |
| Clear Lake City Water Authority | Harris | 89,702 | Community | Purchased surface water |
| City of Baytown | Harris | 86,004 | Community | Purchased surface water |
| City of Houston Ud 5 - Kingwood | Harris | 80,073 | Community | Groundwater |
| Harris County MUD 165 | Harris | 40,503 | 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, “Northwest Harris County MUD 23, PWSID TX1011746, Texas”, https://aquacensus.com/water-systems/texas/northwest-harris-county-mud-23-tx1011746 (data as of October 1, 2026).