Skip to content
AquaCensus

Public water system · CA1010030

Active

Tranquillity Irrigation District

At a glance

Tranquillity Irrigation District (PWSID CA1010030) is an active community water system in Fresno County, California. It reports serving 807 people through 340 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 8 are health-based, and the most recent began in October 2025.

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

Population served

807

Service connections

340

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDCA1010030
System typeCommunity water system
Activity statusActive
Population served807
Service connections340
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyCA state drinking water program
City served—
StateCalifornia
ZIP—
CountyFresno County

How does Tranquillity Irrigation District compare with other water systems in Fresno County?

By EPA's size categories, Tranquillity Irrigation District is a small system (501 to 3,300 people). Fresno County has 328 active public water systems. Its population served is well below the county average of 3,205 people per system, and accounts for less than 0.1% of the 1,051,276 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active community water system reports serving 6,703 people, so Tranquillity Irrigation District is well below that figure.

What does “community water system” mean?

A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. California has 2,997 active 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 Tranquillity Irrigation District?

EPA lists Tranquillity Irrigation District 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. 89 of the 328 active systems in Fresno County (27%) are also owned by a local government.

Does Tranquillity Irrigation District have drinking water violations?

Of the 12 most recent violations in EPA's records, 8 are health-based, and the most recent began in October 2025. The violations listed here began between October 2014 and October 2025. By type: 7 contaminant level above the legal limit, 2 monitoring and reporting, 1 required treatment not met, 1 reporting and 1 monitoring. The contaminant or rule involved most often is Arsenic (4 of them). EPA lists 6 as resolved, 4 as archived and 2 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.

BeganViolationContaminant or ruleHealth-basedStatus
2025-10-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Arseniccode 1005YesArchived
2025-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Arseniccode 1005YesArchived
2025-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Arseniccode 1005YesArchived
2025-01-31Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Arseniccode 1005YesArchived
2024-10-17Required treatment not metLSL Inventory · code 2ELead and Copper Rule Revisionscode 5200YesUnaddressed
2024-10-17ReportingLSL Reporting · code 4GLead and Copper Rule Revisionscode 5200NoUnaddressed
2024-10-01Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52Lead and Copper Rulecode 5000NoResolved
2017-11-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2015-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2015-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2014-12-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2014-10-01Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52Lead and Copper Rulecode 5000NoResolved

The 12 most recent 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.

Tranquillity Irrigation District: frequently asked questions

Who runs Tranquillity Irrigation District?

Tranquillity Irrigation District (PWSID CA1010030) is a community water system owned by a local government. It is regulated by the CA state drinking water program.

How many people does Tranquillity Irrigation District serve?

Tranquillity Irrigation District reports serving 807 people through 340 service connections in Fresno County, California.

Where does Tranquillity Irrigation District 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 Tranquillity Irrigation District have any drinking water violations?

Of the 12 most recent violations in EPA's records, 8 are health-based, and the most recent began in October 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 Tranquillity Irrigation District'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. Of the 12 most recent violations in EPA's records, 8 are health-based, and the most recent began in October 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the CA state drinking water program.

Where can I find Tranquillity Irrigation District's water quality report?

As a community water system, Tranquillity Irrigation District must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.

Other water systems in Fresno County

Water systemCountyPopulation servedTypeSource
City of FresnoFresno545,716CommunitySurface water
City of ClovisFresno130,130CommunitySurface water
California State University FresnoFresno41,000CommunityGroundwater
Cws - SelmaFresno26,517CommunityGroundwater
City of SangerFresno26,357CommunityGroundwater
Reedley, City ofFresno26,076CommunityGroundwater

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, “Tranquillity Irrigation District, PWSID CA1010030, California”, https://aquacensus.com/water-systems/california/tranquillity-irrigation-district-ca1010030 (data as of October 1, 2026).