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Public water system · CA2201070

Active

Mariposa District Fairground

At a glance

Mariposa District Fairground (PWSID CA2201070) is an active transient non-community water system in Mariposa County, California. It reports serving 200 people through 91 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 3 violations for this system; none is health-based, and the most recent began in April 2025.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

200

Service connections

91

Primary source

GW

Groundwater

System type

TNCWS

Transient non-community water system

System record

PWSIDCA2201070
System typeTransient non-community water system
Activity statusActive
Population served200
Service connections91
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyCA state drinking water program
City served—
StateCalifornia
ZIP—
CountyMariposa County

How does Mariposa District Fairground compare with other water systems in Mariposa County?

By EPA's size categories, Mariposa District Fairground is a very small system (500 people or fewer). Mariposa County has 67 active public water systems. Its population served is about half of the county average of 381 people per system, and accounts for 0.8% of the 25,508 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 Mariposa District Fairground is about 39% 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 Mariposa District Fairground?

EPA lists Mariposa District Fairground 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. 21 of the 67 active systems in Mariposa County (31%) are also owned by a local government.

Does Mariposa District Fairground have drinking water violations?

EPA's records list 3 violations for this system; none is health-based, and the most recent began in April 2025. The violations listed here began between January 2002 and April 2025. By type: 2 monitoring and reporting and 1 monitoring. The contaminant or rule involved most often is Nitrate (2 of them). EPA lists 2 as resolved and 1 as archived. 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. 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.

BeganViolationContaminant or ruleHealth-basedStatus
2025-04-01MonitoringMonitoring, Lab Certification/Method Error (RTCR) · code 3DRevised Total Coliform Rulecode 8000NoResolved
2025-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoArchived
2002-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved

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.

Mariposa District Fairground: frequently asked questions

Who runs Mariposa District Fairground?

Mariposa District Fairground (PWSID CA2201070) 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 Mariposa District Fairground serve?

Mariposa District Fairground reports serving 200 people through 91 service connections in Mariposa County, California.

Where does Mariposa District Fairground 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 Mariposa District Fairground have any drinking water violations?

EPA's records list 3 violations for this system; none is health-based, and the most recent began in April 2025. 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 Mariposa District Fairground'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 April 2025. For current results, consult EPA ECHO, or the CA state drinking water program.

Where can I find Mariposa District Fairground's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. Mariposa District Fairground 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 Mariposa County

Water systemCountyPopulation servedTypeSource
Yosemite Nps-Glacier PointMariposa4,000Transient non-communitySurface water
Blm-Briceburg Water SystemMariposa3,196Transient non-communityGroundwater
Mariposa Public Utility DistMariposa2,000CommunitySurface water
Yosemite Nps-Bridalveil FallMariposa1,163Transient non-communityGroundwater
Mid - Mc Swain Rec AreaMariposa1,119Transient non-communitySurface water
Yosemite Nps-Yosemite ValleyMariposa1,000CommunityGroundwater

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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, “Mariposa District Fairground, PWSID CA2201070, California”, https://aquacensus.com/water-systems/california/mariposa-district-fairground-ca2201070 (data as of October 1, 2026).