What's in ATASCADERO MUTUAL WATER CO's water?
ATASCADERO MUTUAL WATER CO has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. 30,618 people get their water from it, across 11,032 connections.
ATASCADERO MUTUAL WATER CO's record against the rest of the country
Out of 12,903 systems in this dataset, ATASCADERO MUTUAL WATER CO ranks 9,092th by violation burden (30th percentile) - 2 violations total, 1 health-based.
Against the CA average
CA's 803 covered systems average 5.8 health-based violations each; ATASCADERO MUTUAL WATER CO carries 1, not more than typical for the state. The filter guide explains what a violation like this actually calls for.
Most recent violation on record
ATASCADERO MUTUAL WATER CO's most recent violation on record is dated 1993-01-06, with the most recent health-based one dated 1993-01-06. Last reported to EPA: 06/22/2026.
The concern categories on record
ATASCADERO MUTUAL WATER CO'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:
- Microbial contamination / treatment technique - flagged from: Surface Water Treatment Rule
The most severe category on record is microbial contamination / treatment technique, which points toward a microbial-class filter if you want to address it directly.
What ATASCADERO MUTUAL WATER CO's record does not cover
ATASCADERO MUTUAL WATER CO'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. Between the utility's meter and ATASCADERO MUTUAL WATER CO's customers' taps is household plumbing, invisible to a system-level record ranked 9,092th of 12,903 by violation count. The guide to what this data misses covers that gap.