Public water system · CA3100538

Active

Rosecrest Mutual

At a glance

Rosecrest Mutual (PWSID CA3100538) is an active community water system in Placer County, California. It reports serving 31 people through 15 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 10 violations for this system; 1 is health-based, and the most recent began in March 2016.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

Service connections

Primary source

Groundwater

System type

CWS

Community water system

System record

PWSIDCA3100538

System typeCommunity water system

Activity statusActive

Population served31

Service connections15

Primary water sourceGroundwater

Owner typePrivate

Primacy agencyCA state drinking water program

City served—

StateCalifornia

ZIP—

CountyPlacer County

How does Rosecrest Mutual compare with other water systems in Placer County?

By EPA's size categories, Rosecrest Mutual is a very small system (500 people or fewer). Placer County has 116 active public water systems. Its population served is well below the county average of 3,692 people per system, and accounts for less than 0.1% of the 428,242 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 Rosecrest Mutual 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. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,179 California systems (83%) list groundwater as their primary source.

Who owns and regulates Rosecrest Mutual?

EPA lists Rosecrest Mutual 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. 78 of the 116 active systems in Placer County (67%) are also privately owned.

Does Rosecrest Mutual have drinking water violations?

EPA's records list 10 violations for this system; 1 is health-based, and the most recent began in March 2016. The violations listed here began between October 1980 and March 2016. By type: 6 monitoring and reporting, 3 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 6 as resolved and 4 as archived. 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. 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
2016-03-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
2016-03-01	Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26	Total coliform bacteria (TCR)code 3100	No	Resolved
2007-07-01	Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71	Consumer Confidence Rulecode 7000	No	Resolved
2007-01-01	Monitoring and reportingMonitoring, Regular · code 03	Radium-228code 4030	No	Resolved
2000-01-01	Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51	Lead and Copper Rulecode 5000	No	Resolved
1993-07-01	Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51	Lead and Copper Rulecode 5000	No	Resolved
1983-08-01	Public notice, recordkeeping or otherNotification, Public · code 06	Not reported	No	Archived
1983-07-01	Public notice, recordkeeping or otherNotification, Public · code 06	Not reported	No	Archived
1981-10-01	Monitoring and reportingMonitoring, Regular · code 03	Gross alpha (excluding radon and uranium)code 4000	No	Archived
1980-10-30	Monitoring and reportingMonitoring, Regular · code 03	Gross alpha (excluding radon and uranium)code 4000	No	Archived

All 10 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.

Rosecrest Mutual: frequently asked questions

Who runs Rosecrest Mutual?

Rosecrest Mutual (PWSID CA3100538) is a community water system privately owned. It is regulated by the CA state drinking water program.

How many people does Rosecrest Mutual serve?

Rosecrest Mutual reports serving 31 people through 15 service connections in Placer County, California.

Where does Rosecrest Mutual get its water?

EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.

Does Rosecrest Mutual have any drinking water violations?

EPA's records list 10 violations for this system; 1 is health-based, and the most recent began in March 2016. 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 Rosecrest Mutual'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 10 violations for this system; 1 is health-based, and the most recent began in March 2016. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.

Where can I find Rosecrest Mutual's water quality report?

As a community water system, Rosecrest Mutual 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 Placer County

Water system	County	Population served	Type	Source
City of Roseville	Placer	155,612	Community	Surface water
Placer Cwa - Foothill	Placer	89,544	Community	Surface water
City of Lincoln	Placer	54,538	Community	Purchased surface water
Placer Cwa - Auburn/Bowman	Placer	27,294	Community	Surface water
Northstar C.S.D.	Placer	15,452	Community	Surface water
Cal Am - West Placer	Placer	8,861	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, “Rosecrest Mutual, PWSID CA3100538, California”, https://aquacensus.com/water-systems/california/rosecrest-mutual-ca3100538 (data as of October 1, 2026).