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Water system · PWSID GU0000006

GWA NORTHERN WATER SYSTEM

MANGILAO, GU · ~139,207 people served

Check your exact address → MANGILAO overview
40
Action needed
PurityRadar safety score

PWSID

GU0000006

State

Guam

City

MANGILAO

Population served

139,207

Primary source

Groundwater

Score history

▼ 60 points — the score moved from 100 to 40 on Jun 18, 2026, as newly published EPA data was incorporated.

Jun 18, 2026 · score 100 Jun 18, 2026 · score 40

2 score updates logged since tracking began Jun 18, 2026. Each future EPA re-score adds a point.

PFAS & contaminant readings

Latest detections from EPA’s UCMR5 monitoring (through Nov 2024). Levels in parts per trillion (ppt).

PFOA

Perfluorooctanoic acid

11 ppt

limit 4 ppt

Above EPA limit · 2.6×

PFOS

Perfluorooctanesulfonic acid

7 ppt

limit 4 ppt

Above EPA limit · 1.8×

PFHxS

Perfluorohexanesulfonic acid

3.2 ppt

limit 10 ppt

Below EPA limit

PFBA

12 ppt

limit —

No federal limit

8:2 FTS

7.5 ppt

limit —

No federal limit

6:2 FTS

6.8 ppt

limit —

No federal limit

PFPeS

5.6 ppt

limit —

No federal limit

PFPeA

5.4 ppt

limit —

No federal limit

PFBS

4.7 ppt

limit —

No federal limit

PFHxA

4.4 ppt

limit —

No federal limit

PFHpA

4 ppt

limit —

No federal limit

Violations & enforcement

No violations are on record for this system in EPA’s SDWIS/ECHO data.

This profile is built from EPA public records for system GU0000006 — SDWIS violations and UCMR5 PFAS sampling. The score is system-level and can’t account for your home’s plumbing (older pipes can add lead at the tap). For health decisions, check your exact address, read the utility’s Consumer Confidence Report, and confirm with your provider.