Public water system · CA2600699
ActiveChalfant Valley West M.W.C.
At a glance
Chalfant Valley West M.W.C. (PWSID CA2600699) is an active community water system in Mono County, California. It reports serving 45 people through 15 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list one violation for this system; it is not health-based, and the most recent began in August 2019.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
45
Service connections
15
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Chalfant Valley West M.W.C. compare with other water systems in Mono County?
By EPA's size categories, Chalfant Valley West M.W.C. is a very small system (500 people or fewer). Mono County has 84 active public water systems. Its population served is well below the county average of 424 people per system, and accounts for 0.1% of the 35,602 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 Chalfant Valley West M.W.C. 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 Chalfant Valley West M.W.C.?
EPA lists Chalfant Valley West M.W.C. 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 84 active systems in Mono County (55%) are also privately owned.
Does Chalfant Valley West M.W.C. have drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in August 2019. By type: 1 monitoring. The contaminant or rule involved is Revised Total Coliform Rule. EPA lists 1 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 |
|---|---|---|---|---|
| 2019-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
The one violation in EPA's records. 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.
Chalfant Valley West M.W.C.: frequently asked questions
Who runs Chalfant Valley West M.W.C.?
Chalfant Valley West M.W.C. (PWSID CA2600699) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Chalfant Valley West M.W.C. serve?
Chalfant Valley West M.W.C. reports serving 45 people through 15 service connections in Mono County, California.
Where does Chalfant Valley West M.W.C. 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 Chalfant Valley West M.W.C. have any drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in August 2019. 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 Chalfant Valley West M.W.C.'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 one violation for this system; it is not health-based, and the most recent began in August 2019. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Chalfant Valley West M.W.C.'s water quality report?
As a community water system, Chalfant Valley West M.W.C. 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 Mono County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Mammoth Cwd | Mono | 8,234 | Community | Surface water |
| Mammoth Mountain Ski Area - Outpost 14 | Mono | 7,736 | Non-transient non-community | Groundwater |
| June Lake PUD - Down Canyon | Mono | 2,810 | Community | Surface water |
| June Lake PUD Village | Mono | 2,763 | Community | Surface water |
| Usmc/Mtn Warfare Trng Ctr - Bridgeport | Mono | 1,200 | Community | Groundwater |
| Mammoth Lakes Basin | Mono | 1,000 | Transient non-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, “Chalfant Valley West M.W.C., PWSID CA2600699, California”, https://aquacensus.com/water-systems/california/chalfant-valley-west-m-w-c-ca2600699 (data as of October 1, 2026).