Public water system · CA3310022
ActiveLake Hemet Mwd
At a glance
Lake Hemet Mwd (PWSID CA3310022) is an active community water system in Riverside County, California. It reports serving 52,913 people through 14,439 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in July 2022.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
52,913
Service connections
14,439
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Lake Hemet Mwd compare with other water systems in Riverside County?
By EPA's size categories, Lake Hemet Mwd is a large system (10,001 to 100,000 people). Riverside County has 197 active public water systems. Its population served is about 3.7 times the county average of 14,435 people per system, and accounts for 1.9% of the 2,843,721 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 Lake Hemet Mwd is about 7.9 times 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 Lake Hemet Mwd?
EPA lists Lake Hemet Mwd 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. 50 of the 197 active systems in Riverside County (25%) are also owned by a local government.
Does Lake Hemet Mwd have drinking water violations?
EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in July 2022. The violations listed here began between October 2002 and July 2022. By type: 2 monitoring and reporting and 2 contaminant level above the legal limit. The contaminants or rules involved are E. coli, Revised Total Coliform Rule, Nitrite and Total coliform bacteria (TCR). 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 |
|---|---|---|---|---|
| 2022-07-01 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2022-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2009-04-01 | Monitoring and reportingMonitoring, Check/Repeat/Confirmation · code 04 | Nitritecode 1041 | No | Resolved |
| 2002-10-01 | 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.
Lake Hemet Mwd: frequently asked questions
Who runs Lake Hemet Mwd?
Lake Hemet Mwd (PWSID CA3310022) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Lake Hemet Mwd serve?
Lake Hemet Mwd reports serving 52,913 people through 14,439 service connections in Riverside County, California.
Where does Lake Hemet Mwd 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 Lake Hemet Mwd have any drinking water violations?
EPA's records list 4 violations for this system; 2 are health-based, and the most recent began in July 2022. 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 Lake Hemet Mwd'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; 2 are health-based, and the most recent began in July 2022. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.
Where can I find Lake Hemet Mwd's water quality report?
As a community water system, Lake Hemet Mwd 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 Riverside County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Eastern Municipal Wd | Riverside | 666,581 | Community | Purchased surface water |
| Riverside, City of | Riverside | 298,398 | Community | Groundwater under influence of surface water |
| Coachella Vwd: Cove Community | Riverside | 270,000 | Community | Groundwater |
| Elsinore Valley Mwd | Riverside | 169,455 | Community | Surface water |
| Corona, City of | Riverside | 168,575 | Community | Purchased surface water |
| Rancho California Water District | Riverside | 146,147 | Community | Purchased 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, “Lake Hemet Mwd, PWSID CA3310022, California”, https://aquacensus.com/water-systems/california/lake-hemet-mwd-ca3310022 (data as of October 1, 2026).