Public water system · CA5510500
ActiveYosemite Nps-Tuolumne Meadows
At a glance
Yosemite Nps-Tuolumne Meadows (PWSID CA5510500) is an active transient non-community water system in Tuolumne County, California. It reports serving 2,500 people through 6 service connections. Its primary water source is surface water, and EPA lists it as owned by the federal government. EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in June 2010.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
2,500
Service connections
6
Primary source
SW
Surface water
System type
TNCWS
Transient non-community water system
System record
How does Yosemite Nps-Tuolumne Meadows compare with other water systems in Tuolumne County?
By EPA's size categories, Yosemite Nps-Tuolumne Meadows is a small system (501 to 3,300 people). Tuolumne County has 117 active public water systems. Its population served is about 3.5 times the county average of 706 people per system, and accounts for 3% of the 82,611 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 Yosemite Nps-Tuolumne Meadows is about 17 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. 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 Yosemite Nps-Tuolumne Meadows?
EPA lists Yosemite Nps-Tuolumne Meadows 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. 22 of the 117 active systems in Tuolumne County (19%) are also owned by the federal government.
Does Yosemite Nps-Tuolumne Meadows have drinking water violations?
EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in June 2010. The violations listed here began between July 2005 and June 2010. By type: 3 required treatment not met and 1 monitoring and reporting. The contaminant or rule involved most often is Interim Enhanced Surface Water Treatment Rule (3 of them). EPA lists 4 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 |
|---|---|---|---|---|
| 2010-06-01 | Required treatment not metMonthly Turbidity Exceed (Enhanced SWTR) · code 44 | Interim Enhanced Surface Water Treatment Rulecode 0300 | Yes | Resolved |
| 2009-05-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-07-01 | Required treatment not metMonthly Turbidity Exceed (Enhanced SWTR) · code 44 | Interim Enhanced Surface Water Treatment Rulecode 0300 | Yes | Resolved |
| 2005-07-01 | Required treatment not metMonthly Turbidity Exceed (Enhanced SWTR) · code 44 | Interim Enhanced Surface Water Treatment Rulecode 0300 | Yes | Resolved |
All 4 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.
Yosemite Nps-Tuolumne Meadows: frequently asked questions
Who runs Yosemite Nps-Tuolumne Meadows?
Yosemite Nps-Tuolumne Meadows (PWSID CA5510500) 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 Yosemite Nps-Tuolumne Meadows serve?
Yosemite Nps-Tuolumne Meadows reports serving 2,500 people through 6 service connections in Tuolumne County, California.
Where does Yosemite Nps-Tuolumne Meadows 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 Yosemite Nps-Tuolumne Meadows have any drinking water violations?
EPA's records list 4 violations for this system; 3 are health-based, and the most recent began in June 2010. 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 Yosemite Nps-Tuolumne Meadows' 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 4 violations for this system; 3 are health-based, and the most recent began in June 2010. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Yosemite Nps-Tuolumne Meadows' water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Yosemite Nps-Tuolumne Meadows 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 Tuolumne County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Tud - Upper Basin Water System | Tuolumne | 13,280 | Community | Surface water |
| Tud - Sonora/Jamestown Water System | Tuolumne | 11,054 | Community | Surface water |
| Tud - Columbia Water System | Tuolumne | 5,463 | Community | Surface water |
| Peppery Bar and Grill, the | Tuolumne | 4,500 | Transient non-community | Groundwater |
| Cdcr - Sierra Conservation Center | Tuolumne | 3,571 | Community | Surface water |
| Groveland Community Serv Dist | Tuolumne | 3,400 | Community | 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, “Yosemite Nps-Tuolumne Meadows, PWSID CA5510500, California”, https://aquacensus.com/water-systems/california/yosemite-nps-tuolumne-meadows-ca5510500 (data as of October 1, 2026).