Public water system record
Three Valleys MWD
Serves Pomona, Diamond Bar, San Dimas and 9 more places, Los Angeles County, CA · Population served not reported
Federal records show no health-based violations and no monitoring or reporting issues for Three Valleys MWD 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
- Three Valleys MWD draws water from 4 wells and 1 surface water intake.
- Record on file since 1988, with 0 health-based violations before October 19, 2016.
Check whether Three Valleys MWD 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 1988
EPA's records for Three Valleys MWD go back to 1988. Before October 19, 2016 they list no health-based violations and 3 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1980s | 0 | 2 |
| 2000s | 0 | 1 |
Where the water comes from
Three Valleys MWD draws water from 4 wells and 1 surface water intake. 7 other community water systems buy water from Three Valleys MWD.
Community systems that buy water from it
- Covina-City, Water Dept. Covina, CA
- GSWC - Claremont San Dimas, CA
- GSWC-San Dimas San Dimas, CA
- La Verne, City WD La Verne, CA
- Pomona - City, Water Dept. Pomona, CA
- Rowland Water District Rowland Heights, CA
- Walnut Valley Water District Walnut, CA
Annual water quality report
Three Valleys MWD 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.
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 California.
Certified drinking water labs by state EPA guidance for private wells