Public water system · CA4010003
ActiveSan Miguelito Mwc
At a glance
San Miguelito Mwc (PWSID CA4010003) is an active community water system in San Luis Obispo County, California. It reports serving 1,600 people through 690 service connections. Its primary water source is purchased surface water, and EPA lists it as privately owned. EPA's records list 3 violations for this system; 2 are health-based, and the most recent began in October 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,600
Service connections
690
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does San Miguelito Mwc compare with other water systems in San Luis Obispo County?
By EPA's size categories, San Miguelito Mwc is a small system (501 to 3,300 people). San Luis Obispo County has 171 active public water systems. Its population served is about 21% below the county average of 2,038 people per system, and accounts for 0.5% of the 348,510 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 San Miguelito Mwc 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 506 California systems (6.8%) list purchased surface water as their primary source.
Who owns and regulates San Miguelito Mwc?
EPA lists San Miguelito Mwc 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. 130 of the 171 active systems in San Luis Obispo County (76%) are also privately owned.
Does San Miguelito Mwc have drinking water violations?
EPA's records list 3 violations for this system; 2 are health-based, and the most recent began in October 2023. The violations listed here began between July 1993 and October 2023. By type: 2 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Total trihalomethanes (TTHM) (2 of them). EPA lists 3 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 |
|---|---|---|---|---|
| 2023-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 2017-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | Yes | Resolved |
| 1993-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
All 3 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.
San Miguelito Mwc: frequently asked questions
Who runs San Miguelito Mwc?
San Miguelito Mwc (PWSID CA4010003) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does San Miguelito Mwc serve?
San Miguelito Mwc reports serving 1,600 people through 690 service connections in San Luis Obispo County, California.
Where does San Miguelito Mwc get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does San Miguelito Mwc have any drinking water violations?
EPA's records list 3 violations for this system; 2 are health-based, and the most recent began in October 2023. 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 San Miguelito Mwc'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 3 violations for this system; 2 are health-based, and the most recent began in October 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find San Miguelito Mwc's water quality report?
As a community water system, San Miguelito Mwc 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 Luis Obispo County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Santa Margarita Recreation Area | San Luis Obispo | 50,001 | Transient non-community | Groundwater |
| San Luis Obispo Water Department | San Luis Obispo | 47,788 | Community | Surface water |
| City of Paso Robles Water Division | San Luis Obispo | 31,176 | Community | Surface water |
| Atascadero Mutual Water Co | San Luis Obispo | 30,618 | Community | Groundwater |
| City of Arroyo Grande Utilities Division | San Luis Obispo | 17,963 | Community | Purchased surface water |
| California Mens Colony | San Luis Obispo | 15,000 | 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, “San Miguelito Mwc, PWSID CA4010003, California”, https://aquacensus.com/water-systems/california/san-miguelito-mwc-ca4010003 (data as of October 1, 2026).