Public water system · OK1021691
ActiveGrand Lake Pwa
At a glance
Grand Lake Pwa (PWSID OK1021691) is an active community water system in Delaware County, Oklahoma. It reports serving 2,800 people through 1,327 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, 3 are health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,800
Service connections
1,327
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Grand Lake Pwa compare with other water systems in Delaware County?
By EPA's size categories, Grand Lake Pwa is a small system (501 to 3,300 people). Delaware County has 35 active public water systems, and Grand Lake Pwa is the 2nd-largest of them by population served. Its population served is about 3.9 times the county average of 714 people per system, and accounts for 11% of the 24,973 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 Grand Lake Pwa is about 58% 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 Grand Lake Pwa?
EPA lists Grand Lake Pwa 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. 13 of the 35 active systems in Delaware County (37%) are also owned by a local government.
Does Grand Lake Pwa have drinking water violations?
Of the 12 most recent violations in EPA's records, 3 are health-based, and the most recent began in July 2025. The violations listed here began between January 2022 and July 2025. By type: 8 monitoring and reporting, 3 contaminant level above the legal limit and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Combined Radium (-226 and -228) (5 of them). EPA lists 10 as resolved and 2 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 |
|---|---|---|---|---|
| 2025-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Archived |
| 2024-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2024-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Resolved |
| 2023-10-02 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2023-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Combined Radium (-226 and -228)code 4010 | Yes | Archived |
| 2022-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross Beta Particle Activitycode 4100 | No | Resolved |
| 2022-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | No | Resolved |
| 2022-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 2022-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Uraniumcode 4006 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross Beta Particle Activitycode 4100 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | No | Resolved |
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Combined Radium (-226 and -228)code 4010 | 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.
Grand Lake Pwa: frequently asked questions
Who runs Grand Lake Pwa?
Grand Lake Pwa (PWSID OK1021691) is a community water system owned by a local government. It is regulated by the OK state drinking water program.
How many people does Grand Lake Pwa serve?
Grand Lake Pwa reports serving 2,800 people through 1,327 service connections in Delaware County, Oklahoma.
Where does Grand Lake Pwa 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 Grand Lake Pwa have any drinking water violations?
Of the 12 most recent violations in EPA's records, 3 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 Grand Lake Pwa'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, 3 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 OK state drinking water program.
Where can I find Grand Lake Pwa's water quality report?
As a community water system, Grand Lake Pwa 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 Delaware County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Grove Municipal Services Auth. | Delaware | 7,311 | Community | Surface water |
| Jay | Delaware | 2,482 | Community | Surface water |
| Ketchum Pwa Delaware Co System | Delaware | 1,805 | Community | Surface water |
| South Delaware Co Regional Water Auth. | Delaware | 1,500 | Community | Surface water |
| Delaware Co Rwd #10 | Delaware | 1,295 | Community | Groundwater |
| West Siloam Springs | Delaware | 877 | 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, “Grand Lake Pwa, PWSID OK1021691, Oklahoma”, https://aquacensus.com/water-systems/oklahoma/grand-lake-pwa-ok1021691 (data as of October 1, 2026).