Zone 7 Water Agency
EPA ID: CA0110010 · 40 people served · 14 ZIP codes
ZipCheckup's reading of EPA records for Zone 7 Water Agency (CA0110010): no drinking-water violations recorded since 2021. Federal monitoring records show zero violations at Zone 7 Water Agency for the reporting cycles they cover, at a utility serving approximately 40 residents.
Data: EPA SDWIS
Service Area Map
Coverage area for Zone 7 Water Agency Source: EPA SDWIS service area boundaries.
Service area boundary
Demographics of ZIP Codes Served
The ZIP codes associated with Zone 7 Water Agency have a median household income of $187,145 and about 524,763 residents live in those ZIP codes (Census; not the number of people this system supplies). Approximately 45% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
🌊 Where Does Your Water Come From?
Zone 7 Water Agency's water is drawn from rivers, lakes, or reservoirs. Surface water sources are more exposed to agricultural runoff, stormwater, and upstream discharges, but they typically receive more intensive treatment before reaching your tap.
Infrastructure Risk
PFAS in ZIP Codes This System Serves
PFAS ("forever chemicals") have been reported in samples from water systems associated with the ZIP codes in this system's area. These results can come from other water systems serving the same ZIP codes; check the UCMR5 section for any results reported for this system. 33 detections recorded. 10 detections are above the level of a federal PFAS MCL (4 ppt for PFOA and PFOS), with compliance required from 2029.
Comparable Water Systems
Similar-sized systems in California
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
Zone 7 Water Agency (EPA ID: CA0110010) is a community water system in California that serves approximately 40 people from surface water sources.
This system provides water to 14 ZIP codes across 11 communities.
Violation History
Lead & Copper
EPA Lead and Copper Rule evidence attributed directly to this water system:
| Lead Level | Exceeds Action Level | Sample Date |
|---|---|---|
| 0.0067 mg/L | No | 2021-12-31 |
No copper action-level exceedance record appears for this PWSID in the accepted LCR snapshot. This does not establish a clean copper measurement.
Radon Risk in Service Area
13 of 14 ZIP records with known zones are in EPA Radon Zone 2. 1 of 14 ZIP records with known zones is in EPA Radon Zone 3.
The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.
ZIP Codes Served
Coverage: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by CA or modeled from parcel and building-footprint data.
- 94506 - Danville
- 94539 - Fremont
- 94542 - Hayward
- 94550 - Livermore
- 94551 - Livermore
- 94552 - Castro Valley
- 94566 - Pleasanton
- 94568 - Dublin
- 94582 - San Ramon
- 94586 - Sunol
- 94587 - Union City
- 94588 - Pleasanton
- 95377 - Tracy
- 95391 - Tracy
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for Zone 7 Water Agency (CA0110010) on EPA.gov.
Frequently Asked Questions
Is Zone 7 Water Agency water safe to drink?
The accepted 2026Q2 ECHO snapshot contains zero violation records for Zone 7 Water Agency in the inclusive 2021-2026 record-year window. This is a compliance-record finding, not a guarantee about water at a specific tap.
How many people does Zone 7 Water Agency serve?
Zone 7 Water Agency serves approximately 40 people across 14 ZIP codes in California.
Where does Zone 7 Water Agency get its water?
The primary water source is surface water.
Frequently Asked Questions
How to cite this page
ZipCheckup. (n.d.). Zone 7 Water Agency Water Quality Report, CA. https://zipcheckup.com/water-system/ca0110010/
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title = {{Zone 7 Water Agency Water Quality Report, CA}},
year = {n.d.},
url = {https://zipcheckup.com/water-system/ca0110010/}
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