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Tap water quality report

Gwa Southern 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
5,801
people served
7
health-based violations
GU rankingsLead in GUPFAS in GU
Water source
Surface water
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.

7
health-based violations
15
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2018-01-01 → 2018-01-31
MCL Health-based Resolved 2018-01-01 → 2018-01-31
MCL Health-based Resolved 2018-01-01 → 2018-01-31
MCL Health-based Resolved 2018-01-01 → 2018-01-31
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 Monitoring Archived 1981-06-10 → 1981-07-09
Other Monitoring Archived 1981-02-10 → 1981-03-09
Other Monitoring Archived 1981-01-10 → 1981-02-09

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 single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Lead
0.00089 mg/L 5.9%
of the EPA limit 0.0150 mg/L
 6/6 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 Southern Water

Is Gwa Southern Water tap water safe to drink?

EPA monitoring detected 1 contaminant in Gwa Southern 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 Southern 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 Southern Water serve?

Gwa Southern Water reports serving 5,801 people in GU, per its EPA record.

Has Gwa Southern Water had any water quality violations?

The EPA has 15 violations on file for Gwa Southern Water, of which 7 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.