Public water system · OK2007103
ActiveGrandfield
At a glance
Grandfield (PWSID OK2007103) is an active community water system in Tillman County, Oklahoma. It reports serving 1,110 people through 595 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,110
Service connections
595
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Grandfield compare with other water systems in Tillman County?
By EPA's size categories, Grandfield is a small system (501 to 3,300 people). Tillman County has 7 active public water systems, and Grandfield is the 3rd-largest of them by population served. Its population served is roughly in line with the county average of 1,168 people per system, and accounts for 14% of the 8,179 people reported by systems filed under the county. Across Oklahoma, the 1,254 active systems average 2,907 people each. Nationally, the average active community water system reports serving 6,703 people, so Grandfield is well 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. Oklahoma has 864 active community water systems, 69% of the state's 1,254 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 299 Oklahoma systems (24%) list purchased surface water as their primary source.
Who owns and regulates Grandfield?
EPA lists Grandfield as owned by a local government. The OK 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 7 active systems in Tillman County (100%) are also owned by a local government.
Does Grandfield have drinking water violations?
Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in January 2026. The violations listed here began between September 2023 and January 2026. By type: 10 contaminant level above the legal limit and 2 monitoring and reporting. The contaminant or rule involved most often is Nitrate-Nitrite (8 of them). EPA lists 10 as archived and 2 as resolved. 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. 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 |
|---|---|---|---|---|
| 2026-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2025-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2025-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2025-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2025-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2024-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2024-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2024-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Archived |
| 2024-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2023-12-30 | Monitoring and reportingFailure Submit IDSE/Subpart V Plan Rpt · code 35 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2023-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Archived |
| 2023-09-29 | Monitoring and reportingFailure Submit IDSE/Subpart V Plan Rpt · code 35 | Total trihalomethanes (TTHM)code 2950 | 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.
Grandfield: frequently asked questions
Who runs Grandfield?
Grandfield (PWSID OK2007103) is a community water system owned by a local government. It is regulated by the OK state drinking water program.
How many people does Grandfield serve?
Grandfield reports serving 1,110 people through 595 service connections in Tillman County, Oklahoma.
Where does Grandfield 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 Grandfield have any drinking water violations?
Of the 12 most recent violations in EPA's records, 10 are health-based, and the most recent began in January 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 Grandfield'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, 10 are health-based, and the most recent began in January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the OK state drinking water program.
Where can I find Grandfield's water quality report?
As a community water system, Grandfield 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 Tillman County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Frederick | Tillman | 3,940 | Community | Surface water |
| Tillman Co Rwd #1 | Tillman | 1,500 | Community | Purchased surface water |
| Tipton | Tillman | 916 | Community | Purchased surface water |
| Davidson | Tillman | 375 | Community | Purchased surface water |
| Manitou | Tillman | 278 | Community | Purchased surface water |
| Hollister | Tillman | 60 | Community | Purchased groundwater |
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, “Grandfield, PWSID OK2007103, Oklahoma”, https://aquacensus.com/water-systems/oklahoma/grandfield-ok2007103 (data as of October 1, 2026).