Public water system · TX0910003
ActiveCity of Denison
At a glance
City of Denison (PWSID TX0910003) is an active community water system in Grayson County, Texas. It reports serving 27,500 people through 17,626 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
27,500
Service connections
17,626
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does City of Denison compare with other water systems in Grayson County?
By EPA's size categories, City of Denison is a large system (10,001 to 100,000 people). Grayson County has 50 active public water systems, and City of Denison is the 2nd-largest of them by population served. Its population served is about 8.6 times the county average of 3,197 people per system, and accounts for 17% of the 159,854 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 City of Denison is about 4.1 times 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 328 Texas systems (4.6%) list surface water as their primary source.
Who owns and regulates City of Denison?
EPA lists City of Denison 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. 29 of the 50 active systems in Grayson County (58%) are also owned by a local government.
Does City of Denison have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2025. The violations listed here began between April 2013 and July 2025. By type: 4 public notice, recordkeeping or other, 3 monitoring and reporting, 2 monitoring, 1 reporting, 1 contaminant level above the legal limit and 1 required treatment not met. The contaminant or rule involved most often is Public Notice (4 of them). EPA lists 11 as resolved and 1 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 |
|---|---|---|---|---|
| 2025-07-02 | ReportingNotification, Known or Potential LSL · code 4H | Lead and Copper Rule Revisionscode 5200 | No | Resolved |
| 2023-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2021-02-19 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2019-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Archived |
| 2018-10-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-02-08 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2015-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2015-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2014-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2013-06-26 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2013-05-01 | Required treatment not metSingle Turbidity Exceed (Enhanced SWTR) · code 43 | Interim Enhanced Surface Water Treatment Rulecode 0300 | Yes | Resolved |
| 2013-04-10 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | 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.
City of Denison: frequently asked questions
Who runs City of Denison?
City of Denison (PWSID TX0910003) is a community water system owned by a local government. It is regulated by the TX state drinking water program.
How many people does City of Denison serve?
City of Denison reports serving 27,500 people through 17,626 service connections in Grayson County, Texas.
Where does City of Denison get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does City of Denison have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in July 2025. 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 City of Denison'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, 2 are health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the TX state drinking water program.
Where can I find City of Denison's water quality report?
As a community water system, City of Denison 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 Grayson County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Sherman | Grayson | 43,645 | Community | Surface water |
| City of Van Alstyne | Grayson | 7,000 | Community | Purchased surface water |
| Two Way Sud | Grayson | 6,804 | Community | Groundwater |
| South Grayson Sud | Grayson | 6,750 | Community | Groundwater |
| City of Howe | Grayson | 4,548 | Community | Purchased surface water |
| Tanglewood on Texoma | Grayson | 4,341 | Community | Purchased surface water |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “City of Denison, PWSID TX0910003, Texas”, https://aquacensus.com/water-systems/texas/city-of-denison-tx0910003 (data as of October 1, 2026).