Public water system · CA3010030
ActiveSanta Margarita Water District-Id9
At a glance
Santa Margarita Water District-Id9 (PWSID CA3010030) is an active community water system in Orange County, California. It reports serving 39,684 people through 11,013 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 11 violations for this system; 1 is health-based, and the most recent began in October 2022.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
39,684
Service connections
11,013
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Santa Margarita Water District-Id9 compare with other water systems in Orange County?
By EPA's size categories, Santa Margarita Water District-Id9 is a large system (10,001 to 100,000 people). Orange County has 46 active public water systems. Its population served is about 43% below the county average of 69,606 people per system, and accounts for 1.2% of the 3,201,893 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 Santa Margarita Water District-Id9 is about 5.9 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 506 California systems (6.8%) list purchased surface water as their primary source.
Who owns and regulates Santa Margarita Water District-Id9?
EPA lists Santa Margarita Water District-Id9 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. 34 of the 46 active systems in Orange County (74%) are also owned by a local government.
Does Santa Margarita Water District-Id9 have drinking water violations?
EPA's records list 11 violations for this system; 1 is health-based, and the most recent began in October 2022. The violations listed here began between October 1995 and October 2022. By type: 10 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total trihalomethanes (TTHM) (4 of them). EPA lists 11 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 |
|---|---|---|---|---|
| 2022-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2020-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2013-01-01 | Monitoring and reportingMonitoring, Routine (IDSE) · code 30 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2013-01-01 | Monitoring and reportingMonitoring, Routine (IDSE) · code 30 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2012-10-01 | Monitoring and reportingMonitoring, Routine (IDSE) · code 30 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2012-10-01 | Monitoring and reportingMonitoring, Routine (IDSE) · code 30 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2012-07-01 | Monitoring and reportingMonitoring, Routine (IDSE) · code 30 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2012-07-01 | Monitoring and reportingMonitoring, Routine (IDSE) · code 30 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2011-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Xylenes, Totalcode 2955 | No | Resolved |
| 2011-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1995-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 11 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.
Santa Margarita Water District-Id9: frequently asked questions
Who runs Santa Margarita Water District-Id9?
Santa Margarita Water District-Id9 (PWSID CA3010030) is a community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Santa Margarita Water District-Id9 serve?
Santa Margarita Water District-Id9 reports serving 39,684 people through 11,013 service connections in Orange County, California.
Where does Santa Margarita Water District-Id9 get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Santa Margarita Water District-Id9 have any drinking water violations?
EPA's records list 11 violations for this system; 1 is health-based, and the most recent began in October 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 Santa Margarita Water District-Id9'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 11 violations for this system; 1 is health-based, and the most recent began in October 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 Santa Margarita Water District-Id9's water quality report?
As a community water system, Santa Margarita Water District-Id9 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 Orange County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Irvine Ranch Water District | Orange | 444,800 | Community | Surface water |
| City of Anaheim | Orange | 348,593 | Community | Surface water |
| City of Santa Ana | Orange | 310,539 | Community | Purchased surface water |
| City of Huntington Beach | Orange | 201,000 | Community | Purchased surface water |
| City of Garden Grove | Orange | 174,226 | Community | Purchased surface water |
| Moulton Niguel Water District | Orange | 170,236 | 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, “Santa Margarita Water District-Id9, PWSID CA3010030, California”, https://aquacensus.com/water-systems/california/santa-margarita-water-district-id9-ca3010030 (data as of October 1, 2026).