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Public water system · CA3710012

Active

Rancho Pauma Mutual Wc

At a glance

Rancho Pauma Mutual Wc (PWSID CA3710012) is an active community water system in San Diego County, California. It reports serving 899 people through 387 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in January 2004.

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

Population served

899

Service connections

387

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDCA3710012
System typeCommunity water system
Activity statusActive
Population served899
Service connections387
Primary water sourceGroundwater
Owner typePrivate
Primacy agencyCA state drinking water program
City served—
StateCalifornia
ZIP—
CountySan Diego County

How does Rancho Pauma Mutual Wc compare with other water systems in San Diego County?

By EPA's size categories, Rancho Pauma Mutual Wc is a small system (501 to 3,300 people). San Diego County has 191 active public water systems. Its population served is well below the county average of 19,427 people per system, and accounts for less than 0.1% of the 3,710,459 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 Rancho Pauma Mutual Wc 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 Rancho Pauma Mutual Wc?

EPA lists Rancho Pauma Mutual Wc 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. 101 of the 191 active systems in San Diego County (53%) are also privately owned.

Does Rancho Pauma Mutual Wc have drinking water violations?

Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in January 2004. The violations listed here began between October 1989 and January 2004. By type: 5 monitoring and reporting, 5 contaminant level above the legal limit and 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Nitrate (6 of them). EPA lists 11 as resolved and 1 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.

BeganViolationContaminant or ruleHealth-basedStatus
2004-01-01Monitoring and reportingMonitoring, Check/Repeat/Confirmation · code 04Nitratecode 1040NoResolved
2003-11-01Monitoring and reportingMonitoring, Check/Repeat/Confirmation · code 04Nitratecode 1040NoResolved
2002-11-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Nitratecode 1040YesResolved
2002-11-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01Nitratecode 1040YesResolved
2002-09-01Public notice, recordkeeping or otherOperations Report · code 10Not reportedNoResolved
2002-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Nitratecode 1040YesResolved
2000-01-01Monitoring and reportingMonitoring, Regular · code 03Nitritecode 1041NoResolved
2000-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
1995-12-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
1994-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
1993-07-01Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51Lead and Copper Rulecode 5000NoResolved
1989-10-01Public notice, recordkeeping or otherNotification, Public · code 06Not reportedNoArchived

The 12 most recent 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.

Rancho Pauma Mutual Wc: frequently asked questions

Who runs Rancho Pauma Mutual Wc?

Rancho Pauma Mutual Wc (PWSID CA3710012) is a community water system privately owned. It is regulated by the CA state drinking water program.

How many people does Rancho Pauma Mutual Wc serve?

Rancho Pauma Mutual Wc reports serving 899 people through 387 service connections in San Diego County, California.

Where does Rancho Pauma Mutual Wc 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 Rancho Pauma Mutual Wc have any drinking water violations?

Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in January 2004. 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 Rancho Pauma Mutual Wc'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. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in January 2004. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.

Where can I find Rancho Pauma Mutual Wc's water quality report?

As a community water system, Rancho Pauma Mutual Wc 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 San Diego County

Water systemCountyPopulation servedTypeSource
San Diego, City ofSan Diego1,385,379CommunitySurface water
Helix Water DistrictSan Diego277,668CommunitySurface water
Otay Water DistrictSan Diego238,008CommunityPurchased surface water
Sweetwater AuthoritySan Diego191,282CommunitySurface water
Oceanside, City ofSan Diego171,483CommunityPurchased surface water
Escondido, City ofSan Diego137,044CommunitySurface 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, “Rancho Pauma Mutual Wc, PWSID CA3710012, California”, https://aquacensus.com/water-systems/california/rancho-pauma-mutual-wc-ca3710012 (data as of October 1, 2026).