Public water system · CA1900764
ActiveHenninger Flats
At a glance
Henninger Flats (PWSID CA1900764) is an active transient non-community water system in Los Angeles County, California. It reports serving 50 people through 1 service connection. Its primary water source is surface water, and EPA lists it as owned by a local government. EPA's records list one violation for this system; it is not health-based, and the most recent began in August 1984.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
50
Service connections
1
Primary source
SW
Surface water
System type
TNCWS
Transient non-community water system
System record
How does Henninger Flats compare with other water systems in Los Angeles County?
By EPA's size categories, Henninger Flats is a very small system (500 people or fewer). Los Angeles County has 275 active public water systems. Its population served is well below the county average of 36,762 people per system, and accounts for less than 0.1% 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 transient non-community water system reports serving 144 people, so Henninger Flats is about 65% below that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. California has 3,016 active transient non-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 Henninger Flats?
EPA lists Henninger Flats 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 Henninger Flats have drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in August 1984. By type: 1 public notice, recordkeeping or other. EPA lists 1 as archived. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 1984-08-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
The one violation in EPA's records.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.
Henninger Flats: frequently asked questions
Who runs Henninger Flats?
Henninger Flats (PWSID CA1900764) is a transient non-community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Henninger Flats serve?
Henninger Flats reports serving 50 people through 1 service connection in Los Angeles County, California.
Where does Henninger Flats 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 Henninger Flats have any drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in August 1984. 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 Henninger Flats' 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 one violation for this system; it is not health-based, and the most recent began in August 1984. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Henninger Flats' water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Henninger Flats is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
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, “Henninger Flats, PWSID CA1900764, California”, https://aquacensus.com/water-systems/california/henninger-flats-ca1900764 (data as of October 1, 2026).