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Community Water System · PWS WA5374000

Rolling Hills-Glencairn

Oak Harbor, Washington 98277 - drinking water served from groundwater sources to 872 people, tracked in EPA SDWIS and UCMR5.

872
People served
46
EPA violations
6
Health-based
Untested
UCMR5 result

The verdict

EPA records 46 drinking-water violations at Rolling Hills-Glencairn, 13% of them health-based - below the Washington per-system average.

46
Total EPA violations on record
13%
Health-based (MCL / treatment failure)
872
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Rolling Hills-Glencairn

Rolling Hills-Glencairn is a private-owned community water system that delivers drinking water to 872 residents in Oak Harbor, Washington (Island County) through 451 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 46 total violations for this system , of which 6 (13%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 40 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Nitrate, recorded in 8 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Washington, EPA tracks 4,557 public water systems serving 9,736,844 people, with 314,648 cumulative violations and 20,590 health-based violations on record. About 92% of systems in the state carry at least one violation, and state-wide the average per system is 69 violations. Statewide, 98 of 247 UCMR5-tested systems have reported PFAS detections (39.7%).

Rolling Hills-Glencairn's 46 violations sit below the Washington average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
872
Total Violations
46
Health-Based Violations
6
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
451
County
Island
School/Daycare
No
MCL Violations
6
Monitoring Violations
40
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Nitrate MR 8 2023
Diquat MR 7 2007
TTHM MCL 6 2025
1,2-DIBROMO-3-CHLOROPROPANE MR 4 2007
ETHYLENE DIBROMIDE MR 4 2007
Total Haloacetic Acids (HAA5) MR 3 2024
TTHM MR 3 2024
Revised Total Coliform Rule MON 2 2024
Barium MR 1 1979
Gross Alpha, Excl. Radon and U MR 1 1979
Arsenic MR 1 1979
Mercury MR 1 1979
Selenium MR 1 1979
Cadmium MR 1 1979
Chromium MR 1 1979
Lead and Copper Rule MR 1 2021
Fluoride MR 1 1979

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Rolling Hills-Glencairn.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID WA5374000 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Washington Drinking Water Authority

Washington State Department of Health, Office of Drinking Water is the primacy agency that licenses and inspects Rolling Hills-Glencairn under EPA-delegated authority.

Open WA regulator portal

Source: Washington State Department of Health, Office of Drinking Water

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2025 TTHM MCL 6 SDWIS / WA5374000 / 2950
2024 Total Haloacetic Acids (HAA5) MR 3 SDWIS / WA5374000 / 2456
2024 TTHM MR 3 SDWIS / WA5374000 / 2950
2024 Revised Total Coliform Rule MON 2 SDWIS / WA5374000 / 8000
2023 Nitrate MR 8 SDWIS / WA5374000 / 1040
2021 Lead and Copper Rule MR 1 SDWIS / WA5374000 / 5000
2007 Diquat MR 7 SDWIS / WA5374000 / 2032
2007 1,2-DIBROMO-3-CHLOROPROPANE MR 4 SDWIS / WA5374000 / 2931
2007 ETHYLENE DIBROMIDE MR 4 SDWIS / WA5374000 / 2946
1979 Barium MR 1 SDWIS / WA5374000 / 1010
1979 Gross Alpha, Excl. Radon and U MR 1 SDWIS / WA5374000 / 4000
1979 Arsenic MR 1 SDWIS / WA5374000 / 1005
1979 Mercury MR 1 SDWIS / WA5374000 / 1035
1979 Selenium MR 1 SDWIS / WA5374000 / 1045
1979 Cadmium MR 1 SDWIS / WA5374000 / 1015

How Rolling Hills-Glencairn Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Rolling Hills-Glencairn Washington avg Federal benchmark
Total violations 46 69 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 6 4.5 Indicates a contaminant exceeded a federal MCL
PFAS detection None 39.7% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 872 2,137 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 4,557 regulated public water systems in Washington.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Rolling Hills-Glencairn water safe to drink? ▼
Rolling Hills-Glencairn (PWS ID: WA5374000) has 46 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 872 people using Groundwater sources.
How many people does Rolling Hills-Glencairn serve? ▼
Rolling Hills-Glencairn serves 872 people in Oak Harbor, Washington. It is a Private-owned system using Groundwater water sources with 451 service connections.
What type of violations does Rolling Hills-Glencairn have? ▼
Rolling Hills-Glencairn has 46 total violations: 6 health-based violations (MCL exceedances or treatment failures), 40 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Rolling Hills-Glencairn water? ▼
No PFAS testing data is available for Rolling Hills-Glencairn under the EPA's UCMR5 monitoring program.
What water source does Rolling Hills-Glencairn use? ▼
Rolling Hills-Glencairn uses Groundwater as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.