Public water system · CA1810003
ActiveLassen County Water Works District #1
At a glance
Lassen County Water Works District #1 (PWSID CA1810003) is an active community water system in Lassen County, California. It reports serving 450 people through 147 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in October 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
450
Service connections
147
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Lassen County Water Works District #1 compare with other water systems in Lassen County?
By EPA's size categories, Lassen County Water Works District #1 is a very small system (500 people or fewer). Lassen County has 51 active public water systems. Its population served is roughly in line with the county average of 476 people per system, and accounts for 1.9% of the 24,257 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 Lassen County Water Works District #1 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 Lassen County Water Works District #1?
EPA lists Lassen County Water Works District #1 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. 15 of the 51 active systems in Lassen County (29%) are also owned by a local government.
Does Lassen County Water Works District #1 have drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in October 2025. The violations listed here began between October 2001 and October 2025. By type: 1 monitoring and reporting and 1 contaminant level above the legal limit. The contaminants or rules involved are Lead and Copper Rule and Total coliform bacteria (TCR). EPA lists 1 as addressed and 1 as resolved. Addressed means the violation is not resolved or archived and is covered by formal enforcement. 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 |
|---|---|---|---|---|
| 2025-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Addressed |
| 2001-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 2 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.
Lassen County Water Works District #1: frequently asked questions
Who runs Lassen County Water Works District #1?
Lassen County Water Works District #1 (PWSID CA1810003) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Lassen County Water Works District #1 serve?
Lassen County Water Works District #1 reports serving 450 people through 147 service connections in Lassen County, California.
Where does Lassen County Water Works District #1 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 Lassen County Water Works District #1 have any drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in October 2025. 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 Lassen County Water Works District #1'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 2 violations for this system; 1 is health-based, and the most recent began in October 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Lassen County Water Works District #1's water quality report?
As a community water system, Lassen County Water Works District #1 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 Lassen County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Susanville | Lassen | 7,811 | Community | Groundwater |
| Cdcr-High Desert State Prison | Lassen | 3,857 | Community | Groundwater |
| Herlong Public Utility District | Lassen | 2,114 | Community | Groundwater |
| Westwood C.S.D. | Lassen | 1,662 | Community | Groundwater |
| Lassen Community College Dist. | Lassen | 1,380 | Non-transient non-community | Groundwater |
| Sierra Army Depot | Lassen | 1,200 | Non-transient non-community | Groundwater |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Lassen County Water Works District #1, PWSID CA1810003, California”, https://aquacensus.com/water-systems/california/lassen-county-water-works-district-1-ca1810003 (data as of October 1, 2026).