Public water system · CA0110010
ActiveZone 7 Water Agency
At a glance
Zone 7 Water Agency (PWSID CA0110010) is an active community water system in Alameda County, California. It reports serving 40 people through 12 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. EPA's records list 2 violations for this system; none is health-based, and the most recent began in June 1995.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
40
Service connections
12
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Zone 7 Water Agency compare with other water systems in Alameda County?
By EPA's size categories, Zone 7 Water Agency is a very small system (500 people or fewer). Alameda County has 27 active public water systems. Its population served is well below the county average of 83,320 people per system, and accounts for less than 0.1% of the 2,249,634 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active community water system reports serving 6,703 people, so Zone 7 Water Agency is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. California has 2,997 active community water systems, 40% of the state's 7,479 active systems. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 609 California systems (8.1%) list surface water as their primary source.
Who owns and regulates Zone 7 Water Agency?
EPA lists Zone 7 Water Agency as owned by a local government. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 15 of the 27 active systems in Alameda County (56%) are also owned by a local government.
Does Zone 7 Water Agency have drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in June 1995. The violations listed here began between June 1995 and June 1995. By type: 2 monitoring and reporting. The contaminants or rules involved are Total coliform bacteria (TCR) and Surface Water Treatment Rule. EPA lists 2 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 1995-06-01 | Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1995-06-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
All 2 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Zone 7 Water Agency: frequently asked questions
Who runs Zone 7 Water Agency?
Zone 7 Water Agency (PWSID CA0110010) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Zone 7 Water Agency serve?
Zone 7 Water Agency reports serving 40 people through 12 service connections in Alameda County, California.
Where does Zone 7 Water Agency get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Zone 7 Water Agency have any drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in June 1995. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Zone 7 Water Agency's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 2 violations for this system; none is health-based, and the most recent began in June 1995. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Zone 7 Water Agency's water quality report?
As a community water system, Zone 7 Water Agency must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Alameda County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| East Bay MUD | Alameda | 1,442,800 | Community | Surface water |
| Alameda County Water District | Alameda | 344,000 | Community | Surface water |
| City of Hayward | Alameda | 162,954 | Community | Purchased surface water |
| Dublin San Ramon Services District | Alameda | 98,776 | Community | Purchased surface water |
| City of Pleasanton | Alameda | 76,689 | Community | Purchased surface water |
| California Water Service - Livermore | Alameda | 60,414 | Community | Purchased surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Zone 7 Water Agency, PWSID CA0110010, California”, https://aquacensus.com/water-systems/california/zone-7-water-agency-ca0110010 (data as of October 1, 2026).