Public water system · CA0400013
ActiveMerry Mountain Mutual
At a glance
Merry Mountain Mutual (PWSID CA0400013) is an active community water system in Butte County, California. It reports serving 90 people through 97 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 October 2022.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
90
Service connections
97
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Merry Mountain Mutual compare with other water systems in Butte County?
By EPA's size categories, Merry Mountain Mutual is a very small system (500 people or fewer). Butte County has 86 active public water systems. Its population served is well below the county average of 2,697 people per system, and accounts for less than 0.1% of the 231,911 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 Merry Mountain 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 Merry Mountain Mutual?
EPA lists Merry Mountain 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. 58 of the 86 active systems in Butte County (67%) are also privately owned.
Does Merry Mountain Mutual have drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in October 2022. The violations listed here began between January 2007 and October 2022. 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 Total coliform bacteria (TCR) (6 of them). EPA lists 12 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 |
|---|---|---|---|---|
| 2022-10-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2022-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2015-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2014-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2014-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2011-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2010-05-01 | 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, Regular · code 03 | Benzenecode 2990 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Carbon tetrachloridecode 2982 | No | Resolved |
| 2009-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2009-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | 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.
Merry Mountain Mutual: frequently asked questions
Who runs Merry Mountain Mutual?
Merry Mountain Mutual (PWSID CA0400013) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Merry Mountain Mutual serve?
Merry Mountain Mutual reports serving 90 people through 97 service connections in Butte County, California.
Where does Merry Mountain 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 Merry Mountain Mutual 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 October 2022. 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 Merry Mountain 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. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in October 2022. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Merry Mountain Mutual's water quality report?
As a community water system, Merry Mountain 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 Butte County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Cal-Water Service Co.-Chico | Butte | 114,925 | Community | Groundwater |
| South Feather W&P - Miners Ranch | Butte | 22,664 | Community | Surface water |
| Butte-Glenn Community College Dist | Butte | 18,000 | Non-transient non-community | Groundwater |
| Thermalito Water & Sewer Dist | Butte | 12,136 | Community | Surface water |
| Cal-Water Service Co.-Oroville | Butte | 11,106 | Community | Surface water |
| Del Oro Water Co.-Paradise Pines | Butte | 10,940 | 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, “Merry Mountain Mutual, PWSID CA0400013, California”, https://aquacensus.com/water-systems/california/merry-mountain-mutual-ca0400013 (data as of October 1, 2026).