Is RIO ALTO WATER DISTRICT's water safe to drink?
RIO ALTO WATER DISTRICT has a health-based violation on record, but none in the last five years - an older issue, not necessarily a current one. Population served: 3,329, over 1,433 connections.
How this compares nationally
RIO ALTO WATER DISTRICT has 5 violations on record in total, 2 of thems health-based - ranking it 6,885th of 12,903 systems by violation count, the 47th percentile nationally.
How RIO ALTO WATER DISTRICT compares within CA
RIO ALTO WATER DISTRICT's 2 health-based violations sit within the CA average of 5.8, across 803 systems statewide. The filter guide explains what a violation like this actually calls for.
Most recent violation on record
The last violation EPA has on record for RIO ALTO WATER DISTRICT is from 2015-01-04 (health-based: 2015-01-04). Last reported to EPA: 06/22/2026.
What kind of problem, specifically
RIO ALTO WATER DISTRICT'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: Coliform (TCR)
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 this data is and is not
RIO ALTO WATER DISTRICT'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 RIO ALTO WATER DISTRICT's customers' taps is household plumbing, invisible to a system-level record ranked 6,885th of 12,903 by violation count. The guide to what this data misses covers that gap.