Public water system · OK2002901
ActiveHollis
At a glance
Hollis (PWSID OK2002901) is an active community water system in Harmon County, Oklahoma. It reports serving 2,264 people through 957 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, 9 are health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,264
Service connections
957
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Hollis compare with other water systems in Harmon County?
By EPA's size categories, Hollis is a small system (501 to 3,300 people). Harmon County has 3 active public water systems, and Hollis is the largest of them by population served. Its population served is about 89% above the county average of 1,201 people per system, and accounts for 63% of the 3,602 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 Hollis is about 66% 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. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 701 Oklahoma systems (56%) list groundwater as their primary source.
Who owns and regulates Hollis?
EPA lists Hollis 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. 3 of the 3 active systems in Harmon County (100%) are also owned by a local government.
Does Hollis have drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024. The violations listed here began between April 2017 and October 2024. By type: 9 contaminant level above the legal limit and 3 monitoring and reporting. The contaminant or rule involved most often is Nitrate-Nitrite (9 of them). EPA lists 11 as resolved and 1 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 |
|---|---|---|---|---|
| 2024-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2024-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2022-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2022-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2020-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2018-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2018-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2018-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2018-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2017-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2017-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | Resolved |
| 2017-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitrate-Nitritecode 1038 | Yes | 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.
Hollis: frequently asked questions
Who runs Hollis?
Hollis (PWSID OK2002901) is a community water system owned by a local government. It is regulated by the OK state drinking water program.
How many people does Hollis serve?
Hollis reports serving 2,264 people through 957 service connections in Harmon County, Oklahoma.
Where does Hollis 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 Hollis have any drinking water violations?
Of the 12 most recent violations in EPA's records, 9 are health-based, and the most recent began in October 2024. 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 Hollis' 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, 9 are health-based, and the most recent began in October 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the OK state drinking water program.
Where can I find Hollis' water quality report?
As a community water system, Hollis 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 Harmon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Harmon Water Corp | Harmon | 1,132 | Community | Groundwater |
| Gould Pwa | Harmon | 206 | 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, “Hollis, PWSID OK2002901, Oklahoma”, https://aquacensus.com/water-systems/oklahoma/hollis-ok2002901 (data as of October 1, 2026).