Public water system record
Gwa Northern Water System
Serves Adacao, Dededo, Tamuning and 33 more places, Guam, GU · 139,207 people served
Federal records show no health-based violations and no monitoring or reporting issues for Gwa Northern Water System in the last ten years.
System profile
- Health-based violations, last 10 years
- 0
- Resolved
- 0
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 0
Key facts
- Gwa Northern Water System draws water from 117 wells.
- Record on file since 1979, with 3 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 38,633 unknown out of 38,813 service lines.
Check whether Gwa Northern Water System serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
None since October 2016, and no monitoring or reporting violations either.
Full record since 1979
EPA's records for Gwa Northern Water System go back to 1979. Before October 19, 2016 they list 3 health-based violations (3 archived by EPA without a recorded fix) and 12 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1970s | 0 | 2 |
| 1980s | 3 | 10 |
Most recent health-based violation before October 19, 2016: Mercury, began January 1985, Archived.
Show all 3 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Mercury
Contaminant limit exceeded
|
Jan 29, 1985 | Archived |
|
Mercury
Contaminant limit exceeded
|
Jan 10, 1985 | Archived |
|
Mercury
Contaminant limit exceeded
|
Jan 7, 1985 | Archived |
Where the water comes from
Gwa Northern Water System draws water from 117 wells. 1 smaller public system such as schools, businesses or campgrounds buys water from Gwa Northern Water System. 1 other public water system has an emergency connection to Gwa Northern Water System.
Annual water quality report
Gwa Northern Water System must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by Guam.
Certified drinking water labs by state EPA guidance for private wells