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Tap water quality report

Gwa Central Water

EPA monitoring tested this supplier for 31 contaminants and detected 1. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

31
contaminants tested
1
detected
21,398
people served
63
health-based violations
GU rankingsLead in GUPFAS in GU
Water source
SWP
Ownership
State government
Counties served
Guam

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

63
health-based violations
105
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2022-04-01 → 2022-04-30
MCL Health-based Resolved 2022-04-01 → 2022-04-30
MCL Health-based Resolved 2022-04-01 → 2022-04-30
MCL Health-based Resolved 2022-04-01 → 2022-04-30
MCL Health-based Resolved 2012-01-01 → 2012-03-31
MCL Health-based Resolved 2012-01-01 → 2012-03-31
MCL Health-based Resolved 2012-01-01 → 2012-03-31
MCL Health-based Resolved 2012-01-01 → 2012-03-31
MCL Health-based Resolved 2012-01-01 → 2012-03-31
MCL Health-based Resolved 2012-01-01 → 2012-03-31

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Lead
0.00077 mg/L 5.1%
of the EPA limit 0.0150 mg/L
 7/7 LCR 2025
30 contaminants tested, none detected
11Cl-PF3OUdS4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaHfpo-DaNetfosaaNfdhaNmefosaaPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaLithium

Utility contact

Contact
BORDALLO, MIGUEL
Phone
671-300-6845
Email
mcbordallo@guamwaterworks.org

Frequently asked questions about Gwa Central Water

Is Gwa Central Water tap water safe to drink?

EPA monitoring detected 1 contaminant in Gwa Central Water's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Gwa Central Water's water?

EPA monitoring detected Lead. The full list with the level and data source for each is above.

How many people does Gwa Central Water serve?

Gwa Central Water reports serving 21,398 people in GU, per its EPA record.

Has Gwa Central Water had any water quality violations?

The EPA has 105 violations on file for Gwa Central Water, of which 63 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.