Public water system · CA1907019
ActiveUsfs-Los Alamos S-15
At a glance
Usfs-Los Alamos S-15 (PWSID CA1907019) is an active transient non-community water system in Los Angeles County, California. It reports serving 25 people through 7 service connections. Its primary water source is groundwater, and EPA lists it as owned by the federal government. EPA's records list 5 violations for this system; none is health-based, and the most recent began in July 2015.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
25
Service connections
7
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Usfs-Los Alamos S-15 compare with other water systems in Los Angeles County?
By EPA's size categories, Usfs-Los Alamos S-15 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 Usfs-Los Alamos S-15 is well 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. 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 Usfs-Los Alamos S-15?
EPA lists Usfs-Los Alamos S-15 as owned by the federal 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. 19 of the 275 active systems in Los Angeles County (6.9%) are also owned by the federal government.
Does Usfs-Los Alamos S-15 have drinking water violations?
EPA's records list 5 violations for this system; none is health-based, and the most recent began in July 2015. The violations listed here began between July 2010 and July 2015. By type: 5 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 5 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 |
|---|---|---|---|---|
| 2015-07-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2011-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2011-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 5 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.
Usfs-Los Alamos S-15: frequently asked questions
Who runs Usfs-Los Alamos S-15?
Usfs-Los Alamos S-15 (PWSID CA1907019) is a transient non-community water system owned by the federal government. It is regulated by the CA state drinking water program.
How many people does Usfs-Los Alamos S-15 serve?
Usfs-Los Alamos S-15 reports serving 25 people through 7 service connections in Los Angeles County, California.
Where does Usfs-Los Alamos S-15 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 Usfs-Los Alamos S-15 have any drinking water violations?
EPA's records list 5 violations for this system; none is health-based, and the most recent began in July 2015. 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 Usfs-Los Alamos S-15'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 5 violations for this system; none is health-based, and the most recent began in July 2015. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Usfs-Los Alamos S-15's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Usfs-Los Alamos S-15 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, “Usfs-Los Alamos S-15, PWSID CA1907019, California”, https://aquacensus.com/water-systems/california/usfs-los-alamos-s-15-ca1907019 (data as of October 1, 2026).