Public water system · CA1210012
ActiveRio Dell, City of
At a glance
City of Rio Dell (PWSID CA1210012) is an active community water system in Humboldt County, California. It reports serving 3,300 people through 1,360 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in October 1996.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
3,300
Service connections
1,360
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does City of Rio Dell compare with other water systems in Humboldt County?
By EPA's size categories, City of Rio Dell is a small system (501 to 3,300 people). Humboldt County has 90 active public water systems, and City of Rio Dell is the 6th-largest of them by population served. Its population served is about 122% above the county average of 1,486 people per system, and accounts for 2.5% 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 City of Rio Dell is about half of 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 609 California systems (8.1%) list surface water as their primary source.
Who owns and regulates City of Rio Dell?
EPA lists City of Rio Dell as owned by a local government. 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. 33 of the 90 active systems in Humboldt County (37%) are also owned by a local government.
Does City of Rio Dell have drinking water violations?
EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in October 1996. The violations listed here began between November 1992 and October 1996. By type: 3 contaminant level above the legal limit and 1 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (3 of them). EPA lists 4 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 |
|---|---|---|---|---|
| 1996-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1994-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1993-06-30 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1992-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 4 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.
City of Rio Dell: frequently asked questions
Who runs City of Rio Dell?
City of Rio Dell (PWSID CA1210012) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does City of Rio Dell serve?
City of Rio Dell reports serving 3,300 people through 1,360 service connections in Humboldt County, California.
Where does City of Rio Dell get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does City of Rio Dell have any drinking water violations?
EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in October 1996. 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 City of Rio Dell'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 4 violations for this system; 3 are health-based, and the most recent began in October 1996. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find City of Rio Dell's water quality report?
As a community water system, City of Rio Dell 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 |
| Garberville Sanitary District | Humboldt | 2,041 | 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, “Rio Dell, City of, PWSID CA1210012, California”, https://aquacensus.com/water-systems/california/rio-dell-city-of-ca1210012 (data as of October 1, 2026).