Public water system · CA3500510
ActiveMcmahon Road Mutual Water Company
At a glance
Mcmahon Road Mutual Water Company (PWSID CA3500510) is an active community water system in San Benito County, California. It reports serving 102 people through 32 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, one is health-based, and the most recent began in July 2006.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
102
Service connections
32
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Mcmahon Road Mutual Water Company compare with other water systems in San Benito County?
By EPA's size categories, Mcmahon Road Mutual Water Company is a very small system (500 people or fewer). San Benito County has 63 active public water systems. Its population served is well below the county average of 1,312 people per system, and accounts for 0.1% of the 82,670 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 Mcmahon Road Mutual Water Company 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 Mcmahon Road Mutual Water Company?
EPA lists Mcmahon Road Mutual Water Company 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. 46 of the 63 active systems in San Benito County (73%) are also privately owned.
Does Mcmahon Road Mutual Water Company have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in July 2006. The violations listed here began between November 2000 and July 2006. By type: 10 monitoring and reporting, 1 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Chlorine (5 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 |
|---|---|---|---|---|
| 2006-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2006-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2006-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2005-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2004-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2004-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2004-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2004-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2000-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | 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.
Mcmahon Road Mutual Water Company: frequently asked questions
Who runs Mcmahon Road Mutual Water Company?
Mcmahon Road Mutual Water Company (PWSID CA3500510) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Mcmahon Road Mutual Water Company serve?
Mcmahon Road Mutual Water Company reports serving 102 people through 32 service connections in San Benito County, California.
Where does Mcmahon Road Mutual Water Company 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 Mcmahon Road Mutual Water Company have any drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in July 2006. 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 Mcmahon Road Mutual Water Company'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, one is health-based, and the most recent began in July 2006. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Mcmahon Road Mutual Water Company's water quality report?
As a community water system, Mcmahon Road Mutual Water Company 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 Benito County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Hollister, City of | San Benito | 26,017 | Community | Purchased surface water |
| Sunnyslope County Water Dist | San Benito | 24,954 | Community | Purchased surface water |
| 33rd District Agricultural Association | San Benito | 9,000 | Transient non-community | Groundwater |
| San Benito High School | San Benito | 3,310 | Non-transient non-community | Groundwater |
| Aromas Water District | San Benito | 2,988 | Community | Groundwater |
| San Juan Bautista, City of | San Benito | 2,335 | Community | Groundwater |
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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, “Mcmahon Road Mutual Water Company, PWSID CA3500510, California”, https://aquacensus.com/water-systems/california/mcmahon-road-mutual-water-company-ca3500510 (data as of October 1, 2026).