Public water system · CA1200547
ActiveMill Creek M.W.C.
At a glance
Mill Creek M.W.C. (PWSID CA1200547) is an active community water system in Humboldt County, California. It reports serving 85 people through 36 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, 4 are health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
85
Service connections
36
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Mill Creek M.W.C. compare with other water systems in Humboldt County?
By EPA's size categories, Mill Creek M.W.C. is a very small system (500 people or fewer). Humboldt County has 90 active public water systems. Its population served is well below the county average of 1,486 people per system, and accounts for less than 0.1% of the 133,779 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 Mill Creek 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 Mill Creek M.W.C.?
EPA lists Mill Creek 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. 41 of the 90 active systems in Humboldt County (46%) are also privately owned.
Does Mill Creek M.W.C. have drinking water violations?
Of the 12 most recent violations in EPA's records, 4 are health-based, and the most recent began in October 2024. The violations listed here began between August 1993 and October 2024. By type: 7 monitoring and reporting, 3 contaminant level above the legal limit, 1 reporting and 1 required treatment not met. The contaminant or rule involved most often is Total coliform bacteria (TCR) (9 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 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2023-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2009-12-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2003-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2003-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1994-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1993-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1993-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | 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.
Mill Creek M.W.C.: frequently asked questions
Who runs Mill Creek M.W.C.?
Mill Creek M.W.C. (PWSID CA1200547) is a community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Mill Creek M.W.C. serve?
Mill Creek M.W.C. reports serving 85 people through 36 service connections in Humboldt County, California.
Where does Mill Creek 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 Mill Creek M.W.C. have any drinking water violations?
Of the 12 most recent violations in EPA's records, 4 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 Mill Creek 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. Of the 12 most recent violations in EPA's records, 4 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 Mill Creek M.W.C.'s water quality report?
As a community water system, Mill Creek 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 Humboldt County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Eureka, City of | Humboldt | 27,078 | Community | Purchased groundwater |
| Arcata, City of | Humboldt | 20,875 | Community | Purchased groundwater |
| Humboldt C.S.D. | Humboldt | 19,807 | Community | Groundwater |
| Mckinleyville C.S.D. | Humboldt | 16,900 | Community | Purchased groundwater |
| Fortuna, City of | Humboldt | 12,133 | Community | Groundwater |
| Rio Dell, City of | Humboldt | 3,300 | 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, “Mill Creek M.W.C., PWSID CA1200547, California”, https://aquacensus.com/water-systems/california/mill-creek-m-w-c-ca1200547 (data as of October 1, 2026).