Public water system · CA1910092
ActiveMonterey Park-City, Water Dept.
At a glance
Monterey Park-City, Water Dept. (PWSID CA1910092) is an active community water system in Los Angeles County, California. It reports serving 62,183 people through 13,321 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 3 violations for this system; 1 is health-based, and the most recent began in October 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
62,183
Service connections
13,321
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Monterey Park-City, Water Dept. compare with other water systems in Los Angeles County?
By EPA's size categories, Monterey Park-City, Water Dept. is a large system (10,001 to 100,000 people). Los Angeles County has 275 active public water systems. Its population served is about 69% above the county average of 36,762 people per system, and accounts for 0.6% of the 10,109,668 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 Monterey Park-City, Water Dept. is about 9.3 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 Monterey Park-City, Water Dept.?
EPA lists Monterey Park-City, Water Dept. 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. 100 of the 275 active systems in Los Angeles County (36%) are also owned by a local government.
Does Monterey Park-City, Water Dept. have drinking water violations?
EPA's records list 3 violations for this system; 1 is health-based, and the most recent began in October 2024. The violations listed here began between April 2005 and October 2024. By type: 1 required treatment not met, 1 reporting and 1 monitoring and reporting. The contaminant or rule involved most often is Lead and Copper Rule Revisions (2 of them). EPA lists 2 as unaddressed and 1 as resolved. Unaddressed means the violation is not resolved or archived and is not yet 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 |
|---|---|---|---|---|
| 2024-10-17 | Required treatment not metLSL Inventory · code 2E | Lead and Copper Rule Revisionscode 5200 | Yes | Unaddressed |
| 2024-10-17 | ReportingLSL Reporting · code 4G | Lead and Copper Rule Revisionscode 5200 | No | Unaddressed |
| 2005-04-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | 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.
Monterey Park-City, Water Dept.: frequently asked questions
Who runs Monterey Park-City, Water Dept.?
Monterey Park-City, Water Dept. (PWSID CA1910092) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Monterey Park-City, Water Dept. serve?
Monterey Park-City, Water Dept. reports serving 62,183 people through 13,321 service connections in Los Angeles County, California.
Where does Monterey Park-City, Water Dept. 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 Monterey Park-City, Water Dept. have any drinking water violations?
EPA's records list 3 violations for this system; 1 is 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 Monterey Park-City, Water Dept.'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; 1 is 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 Monterey Park-City, Water Dept.'s water quality report?
As a community water system, Monterey Park-City, Water Dept. 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 Los Angeles County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Los Angeles-City, Dept. of Water & Power | Los Angeles | 3,875,566 | Community | Surface water |
| Long Beach Utilities Department | Los Angeles | 466,772 | Community | Purchased surface water |
| Santa Clarita Valley Water Agency | Los Angeles | 294,090 | Community | Surface water |
| Gswc - Southwest | Los Angeles | 277,740 | Community | Purchased surface water |
| San Gabriel Valley Water Co.-El Monte | Los Angeles | 248,000 | Community | Groundwater |
| Los Angeles Cwwd 40 Reg 4 & 34 Lancaster | Los Angeles | 208,129 | 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, “Monterey Park-City, Water Dept., PWSID CA1910092, California”, https://aquacensus.com/water-systems/california/monterey-park-city-water-dept-ca1910092 (data as of October 1, 2026).