Public water system · CA1700518
ActiveLoch Lomond Mutual Water Co
At a glance
Loch Lomond Mutual Water Co (PWSID CA1700518) is an active community water system in Lake County, California. It reports serving 693 people through 238 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, 2 are health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
693
Service connections
238
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Loch Lomond Mutual Water Co compare with other water systems in Lake County?
By EPA's size categories, Loch Lomond Mutual Water Co is a small system (501 to 3,300 people). Lake County has 81 active public water systems. Its population served is about 23% below the county average of 895 people per system, and accounts for 1% of the 72,454 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 Loch Lomond 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. 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 Loch Lomond Mutual Water Co?
EPA lists Loch Lomond 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. 60 of the 81 active systems in Lake County (74%) are also privately owned.
Does Loch Lomond Mutual Water Co have drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in October 2024. The violations listed here began between June 2002 and October 2024. By type: 8 monitoring and reporting, 1 required treatment not met, 1 reporting, 1 monitoring and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Lead and Copper Rule (5 of them). EPA lists 10 as resolved and 2 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2020-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2018-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2010-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2009-07-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2008-09-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2007-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2002-06-01 | Monitoring and reportingWater Quality Parameter M/R · code 53 | Lead and Copper Rulecode 5000 | No | Resolved |
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.
Loch Lomond Mutual Water Co: frequently asked questions
Who runs Loch Lomond Mutual Water Co?
Loch Lomond Mutual Water Co (PWSID CA1700518) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Loch Lomond Mutual Water Co serve?
Loch Lomond Mutual Water Co reports serving 693 people through 238 service connections in Lake County, California.
Where does Loch Lomond Mutual Water Co 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 Loch Lomond Mutual Water Co have any drinking water violations?
Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in October 2024. 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 Loch Lomond 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. Of the 12 most recent violations in EPA's records, 2 are health-based, and the most recent began in October 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Loch Lomond Mutual Water Co's water quality report?
As a community water system, Loch Lomond 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 Lake County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Highlands Mutual Water Company | Lake | 7,772 | Community | Surface water |
| Hidden Valley Lake Csd | Lake | 6,235 | Community | Groundwater |
| Konocti County Water District | Lake | 5,928 | Community | Surface water |
| Lakeport, City of | Lake | 4,762 | Community | Surface water |
| Golden State Water Co.-Clearlake System | Lake | 4,644 | Community | Surface water |
| Mt. Konocti Mutual Water Company | Lake | 4,360 | Community | 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, “Loch Lomond Mutual Water Co, PWSID CA1700518, California”, https://aquacensus.com/water-systems/california/loch-lomond-mutual-water-co-ca1700518 (data as of October 1, 2026).