Public water system · CA4010900
ActiveCaltrans - Shandon Rest Stop
At a glance
Caltrans - Shandon Rest Stop (PWSID CA4010900) is an active transient non-community water system in San Luis Obispo County, California. It reports serving 1,300 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as owned by a state government. EPA's records list 5 violations for this system; 2 are health-based, and the most recent began in November 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
1,300
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Caltrans - Shandon Rest Stop compare with other water systems in San Luis Obispo County?
By EPA's size categories, Caltrans - Shandon Rest Stop is a small system (501 to 3,300 people). San Luis Obispo County has 171 active public water systems. Its population served is about 36% below the county average of 2,038 people per system, and accounts for 0.4% of the 348,510 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 Caltrans - Shandon Rest Stop is about 9 times 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 Caltrans - Shandon Rest Stop?
EPA lists Caltrans - Shandon Rest Stop as owned by a state 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. 6 of the 171 active systems in San Luis Obispo County (3.5%) are also owned by a state government.
Does Caltrans - Shandon Rest Stop have drinking water violations?
EPA's records list 5 violations for this system; 2 are health-based, and the most recent began in November 2024. The violations listed here began between January 1994 and November 2024. By type: 3 monitoring and reporting and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 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 |
|---|---|---|---|---|
| 2024-11-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2014-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2012-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1994-02-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1994-01-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | 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.
Caltrans - Shandon Rest Stop: frequently asked questions
Who runs Caltrans - Shandon Rest Stop?
Caltrans - Shandon Rest Stop (PWSID CA4010900) is a transient non-community water system owned by a state government. It is regulated by the CA state drinking water program.
How many people does Caltrans - Shandon Rest Stop serve?
Caltrans - Shandon Rest Stop reports serving 1,300 people through 1 service connection in San Luis Obispo County, California.
Where does Caltrans - Shandon Rest Stop 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 Caltrans - Shandon Rest Stop have any drinking water violations?
EPA's records list 5 violations for this system; 2 are health-based, and the most recent began in November 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 Caltrans - Shandon Rest Stop'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; 2 are health-based, and the most recent began in November 2024. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Caltrans - Shandon Rest Stop's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Caltrans - Shandon Rest Stop 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 Luis Obispo County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Santa Margarita Recreation Area | San Luis Obispo | 50,001 | Transient non-community | Groundwater |
| San Luis Obispo Water Department | San Luis Obispo | 47,788 | Community | Surface water |
| City of Paso Robles Water Division | San Luis Obispo | 31,176 | Community | Surface water |
| Atascadero Mutual Water Co | San Luis Obispo | 30,618 | Community | Groundwater |
| City of Arroyo Grande Utilities Division | San Luis Obispo | 17,963 | Community | Purchased surface water |
| California Mens Colony | San Luis Obispo | 15,000 | Community | Surface water |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Caltrans - Shandon Rest Stop, PWSID CA4010900, California”, https://aquacensus.com/water-systems/california/caltrans-shandon-rest-stop-ca4010900 (data as of October 1, 2026).