GSWC-SAN DIMAS: EPA violation history, explained
GSWC-SAN DIMAS has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. 56,538 people get their water from it, across 16,163 connections.
Ranked against every other system in this dataset
2 total violations and 2 health-based ones put GSWC-SAN DIMAS at the 45th percentile nationally for violation burden, rank 7,049 of 12,903.
How GSWC-SAN DIMAS compares within CA
GSWC-SAN DIMAS's 2 health-based violations sit within the CA average of 5.8, across 803 systems statewide. The clean-record guide covers what a comparison like this can hide.
Most recent violation on record
The last violation EPA has on record for GSWC-SAN DIMAS is from 1997-01-09 (health-based: 1997-01-09). Last reported to EPA: 06/22/2026.
What kind of problem, specifically
GSWC-SAN DIMAS's flagged contaminants and rule violations, grouped by what they actually mean for a filter choice rather than left as EPA's raw code list:
- Nitrate / nitrite - flagged from: Nitrate
The most severe category on record is nitrate / nitrite, which points toward a reverse osmosis-class filter if you want to address it directly.
What this data is and is not
GSWC-SAN DIMAS's numbers here come from its own required reporting to EPA under the Safe Drinking Water Act, not from an independent test of your glass of water. Water quality can still change between the meter and the faucet - household plumbing sits outside what a record of 2 logged violations can see. The guide to what this data misses covers that gap.