Public water system · CA4100552
ActiveOptimists Volunteers for Youth
At a glance
Optimists Volunteers for Youth (PWSID CA4100552) is an active transient non-community water system in San Mateo County, California. It reports serving 207 people through 9 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 3 violations for this system; none is health-based, and the most recent began in January 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
207
Service connections
9
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Optimists Volunteers for Youth compare with other water systems in San Mateo County?
By EPA's size categories, Optimists Volunteers for Youth is a very small system (500 people or fewer). San Mateo County has 51 active public water systems. Its population served is well below the county average of 15,363 people per system, and accounts for less than 0.1% of the 783,522 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 Optimists Volunteers for Youth is about 44% above 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 Optimists Volunteers for Youth?
EPA lists Optimists Volunteers for Youth as privately owned. 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. 27 of the 51 active systems in San Mateo County (53%) are also privately owned.
Does Optimists Volunteers for Youth have drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in January 2024. The violations listed here began between June 1983 and January 2024. By type: 1 monitoring and reporting, 1 monitoring and 1 public notice, recordkeeping or other. The contaminants or rules involved are Nitrate and Revised Total Coliform Rule. EPA lists 2 as archived and 1 as resolved. 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. 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 |
|---|---|---|---|---|
| 2024-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Archived |
| 2020-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 1983-06-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
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.
Optimists Volunteers for Youth: frequently asked questions
Who runs Optimists Volunteers for Youth?
Optimists Volunteers for Youth (PWSID CA4100552) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Optimists Volunteers for Youth serve?
Optimists Volunteers for Youth reports serving 207 people through 9 service connections in San Mateo County, California.
Where does Optimists Volunteers for Youth 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 Optimists Volunteers for Youth have any drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in January 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 Optimists Volunteers for Youth'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; none is health-based, and the most recent began in January 2024. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Optimists Volunteers for Youth's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Optimists Volunteers for Youth 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 San Mateo County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| City of Daly City | San Mateo | 104,901 | Community | Purchased surface water |
| California Water Service - San Mateo | San Mateo | 102,348 | Community | Purchased surface water |
| City of Redwood City | San Mateo | 92,819 | Community | Purchased surface water |
| California Water Service-S San Francisco | San Mateo | 64,146 | Community | Purchased surface water |
| California Water Service - Bear Gulch | San Mateo | 61,431 | Community | Surface water |
| City of San Bruno | San Mateo | 42,631 | 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, “Optimists Volunteers for Youth, PWSID CA4100552, California”, https://aquacensus.com/water-systems/california/optimists-volunteers-for-youth-ca4100552 (data as of October 1, 2026).