Public water system · CA4300842
ActiveDeer Hill Mutual Water Co
At a glance
Deer Hill Mutual Water Co (PWSID CA4300842) is an active community water system in Santa Clara County, California. It reports serving 36 people through 14 service connections. Its primary water source is purchased groundwater, and EPA lists it as privately owned. EPA's records list one violation for this system; it is not health-based, and the most recent began in July 1993.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
36
Service connections
14
Primary source
GWP
Purchased groundwater
System type
CWS
Community water system
System record
How does Deer Hill Mutual Water Co compare with other water systems in Santa Clara County?
By EPA's size categories, Deer Hill Mutual Water Co is a very small system (500 people or fewer). Santa Clara County has 121 active public water systems. Its population served is well below the county average of 17,334 people per system, and accounts for less than 0.1% of the 2,097,447 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 Deer Hill Mutual Water Co 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. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own. 76 California systems (1%) list purchased groundwater as their primary source.
Who owns and regulates Deer Hill Mutual Water Co?
EPA lists Deer Hill Mutual Water Co as privately owned. 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. 82 of the 121 active systems in Santa Clara County (68%) are also privately owned.
Does Deer Hill Mutual Water Co have drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in July 1993. By type: 1 monitoring and reporting. The contaminant or rule involved is Lead and Copper Rule. EPA lists 1 as archived. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 1993-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Archived |
The one violation in EPA's records.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.
Deer Hill Mutual Water Co: frequently asked questions
Who runs Deer Hill Mutual Water Co?
Deer Hill Mutual Water Co (PWSID CA4300842) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Deer Hill Mutual Water Co serve?
Deer Hill Mutual Water Co reports serving 36 people through 14 service connections in Santa Clara County, California.
Where does Deer Hill Mutual Water Co get its water?
EPA SDWIS lists this system's primary water source as purchased groundwater. Purchased groundwater means the system buys groundwater from another public water system rather than drawing its own.
Does Deer Hill Mutual Water Co have any drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in July 1993. 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 Deer Hill Mutual Water Co'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 one violation for this system; it is not health-based, and the most recent began in July 1993. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Deer Hill Mutual Water Co's water quality report?
As a community water system, Deer Hill Mutual Water Co 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 Santa Clara County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| San Jose Water | Santa Clara | 1,039,920 | Community | Surface water |
| City of Sunnyvale | Santa Clara | 157,566 | Community | Purchased surface water |
| City of Santa Clara | Santa Clara | 130,746 | Community | Purchased surface water |
| Great Oaks Wc Inc. | Santa Clara | 110,088 | Community | Groundwater |
| City of San Jose - Evg/Edv/Coy | Santa Clara | 101,265 | Community | Purchased surface water |
| City of Milpitas | Santa Clara | 81,773 | Community | Purchased surface water |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Deer Hill Mutual Water Co, PWSID CA4300842, California”, https://aquacensus.com/water-systems/california/deer-hill-mutual-water-co-ca4300842 (data as of October 1, 2026).