No health-based violations on EPA record since 2016.
Serves about 3,329 people (1,433 connections) with groundwater from its own wells.
From EPA's record for CA5210005. PurityMap is independent of Rio Alto Water District.
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No health-based violations in the last 10 years, from EPA's SDWIS compliance database.
No lab results for other contaminants (like PFAS) are on file for this system. EPA required that testing from systems serving more than 3,300 people, plus a sample of smaller ones.
Screening tells you if something is worth a closer look; a lab result is the number you can act on.
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Screening: quick check, not lab-grade
Safe Home (EnviroTestKits)
Lead, read as one of three ranges: 0–4, 5–15 or 15+ ppb
Turnaround: 5 minutes
What it can't tell you: It shows a lead range, not an exact level, and tests nothing else unless you pay extra for the optional lab test.
Lab-certified results
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
Environmental Testing and Research Laboratories (ETR Labs), Leominster, MA · ISO/IEC 17025:2017, ANAB certificate AT-2638 · 2–4 business days after the lab receives it
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
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Follow this water →Rio Alto Water District's phone number on EPA record is 530-347-3835. Its mailing address is 22099 River View Drive, COTTONWOOD, CA 96022.
According to EPA's record, Rio Alto Water District uses groundwater from its own wells.
No health-based violations on EPA record since 2016. The record comes from EPA's SDWIS compliance database.
Lead was not detected at the 90th percentile of tap samples in Rio Alto Water District's latest lead and copper round, which ended in December 2025. The federal action level is 15 µg/L.
PurityMap has no verified website for Rio Alto Water District. Its phone number on EPA record is 530-347-3835. Its mailing address on EPA record is 22099 River View Drive, COTTONWOOD, CA 96022. Your water bill lists the ways to contact your supplier and pay. PurityMap does not take payments.