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Transient Non-Community Water System · PWS VA6059523

Great Falls Park

McClean, Virginia 22101 - drinking water served from groundwater sources to 2,000 people, tracked in EPA SDWIS and UCMR5.

2,000
People served
59
EPA violations
7
Health-based
Untested
UCMR5 result

The verdict

EPA records 59 drinking-water violations at Great Falls Park, 12% of them health-based - above the Virginia per-system average.

59
Total EPA violations on record
12%
Health-based (MCL / treatment failure)
2,000
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Great Falls Park

Great Falls Park is a federal-owned transient non-community water system that delivers drinking water to 2,000 residents in McClean, Virginia (Fairfax County) through 3 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 59 total violations for this system , of which 7 (12%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 47 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is Revised Total Coliform Rule, recorded in 22 violations (MON). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Virginia, EPA tracks 2,821 public water systems serving 7,911,199 people, with 146,670 cumulative violations and 25,642 health-based violations on record. About 90% of systems in the state carry at least one violation, and state-wide the average per system is 52 violations. Statewide, 70 of 171 UCMR5-tested systems have reported PFAS detections (40.9%).

Great Falls Park's 59 violations sit above the Virginia 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
2,000
Total Violations
59
Health-Based Violations
7
Water Source
Groundwater

System Details

System Type
Transient Non-Community
Owner Type
Federal
Connections
3
County
Fairfax
School/Daycare
No
MCL Violations
7
Monitoring Violations
47
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Revised Total Coliform Rule MON 22 2024
Coliform (TCR) MR 17 2016
Coliform (TCR) MCL 7 2015
Public Notice Other 4 2024
E. COLI MR 3 2015
Nitrate MR 3 1999
Combined Radium (-226 and -228) MR 1 1977
Gross Alpha, Excl. Radon and U MR 1 1977

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 Great Falls Park.

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 VA6059523 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Virginia Drinking Water Authority

Virginia Department of Health, Office of Drinking Water is the primacy agency that licenses and inspects Great Falls Park under EPA-delegated authority.

Open VA regulator portal

Source: Virginia 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
2024 Revised Total Coliform Rule MON 22 SDWIS / VA6059523 / 8000
2024 Public Notice Other 4 SDWIS / VA6059523 / 7500
2016 Coliform (TCR) MR 17 SDWIS / VA6059523 / 3100
2015 Coliform (TCR) MCL 7 SDWIS / VA6059523 / 3100
2015 E. COLI MR 3 SDWIS / VA6059523 / 3014
1999 Nitrate MR 3 SDWIS / VA6059523 / 1040
1977 Combined Radium (-226 and -228) MR 1 SDWIS / VA6059523 / 4010
1977 Gross Alpha, Excl. Radon and U MR 1 SDWIS / VA6059523 / 4000

How Great Falls Park Compares

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

Metric Great Falls Park Virginia avg Federal benchmark
Total violations 59 52 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 7 9.1 Indicates a contaminant exceeded a federal MCL
PFAS detection None 40.9% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 2,000 2,804 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,821 regulated public water systems in Virginia.

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 Great Falls Park water safe to drink? ▼
Great Falls Park (PWS ID: VA6059523) has 59 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 2,000 people using Groundwater sources.
How many people does Great Falls Park serve? ▼
Great Falls Park serves 2,000 people in McClean, Virginia. It is a Federal-owned system using Groundwater water sources with 3 service connections.
What type of violations does Great Falls Park have? ▼
Great Falls Park has 59 total violations: 7 health-based violations (MCL exceedances or treatment failures), 47 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Great Falls Park water? ▼
No PFAS testing data is available for Great Falls Park under the EPA's UCMR5 monitoring program.
What water source does Great Falls Park use? ▼
Great Falls Park uses Groundwater as its primary water source. It is classified as a Transient Non-Community Water System, serving transient populations.
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.