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Public water system · WA5385400

Active

Sunnyside City of

At a glance

City of Sunnyside (PWSID WA5385400) is an active community water system in Yakima County, Washington. It reports serving 17,194 people through 5,456 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, none is health-based, and the most recent began in July 2025.

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

Population served

17,194

Service connections

5,456

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDWA5385400
System typeCommunity water system
Activity statusActive
Population served17,194
Service connections5,456
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyWA state drinking water program
City served—
StateWashington
ZIP—
CountyYakima County

How does City of Sunnyside compare with other water systems in Yakima County?

By EPA's size categories, City of Sunnyside is a large system (10,001 to 100,000 people). Yakima County has 217 active public water systems, and City of Sunnyside is the 3rd-largest of them by population served. Its population served is about 14 times the county average of 1,230 people per system, and accounts for 6.4% of the 266,832 people reported by systems filed under the county. Across Washington, the 4,705 active systems average 2,172 people each. Nationally, the average active community water system reports serving 6,703 people, so City of Sunnyside is about 157% above 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. Washington has 2,392 active community water systems, 51% of the state's 4,705 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 4,370 Washington systems (93%) list groundwater as their primary source.

Who owns and regulates City of Sunnyside?

EPA lists City of Sunnyside as owned by a local government. The WA 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 217 active systems in Yakima County (9.7%) are also owned by a local government.

Does City of Sunnyside have drinking water violations?

Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 2025. The violations listed here began between April 2014 and July 2025. By type: 10 monitoring and reporting, 1 public notice, recordkeeping or other and 1 monitoring. The contaminant or rule involved most often is Total trihalomethanes (TTHM) (5 of them). EPA lists 9 as resolved, 2 as archived and 1 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
2025-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2025-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Haloacetic acids (HAA5)code 2456NoArchived
2025-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Total trihalomethanes (TTHM)code 2950NoArchived
2024-02-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2023-01-01Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52Lead and Copper Rulecode 5000NoUnaddressed
2017-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Haloacetic acids (HAA5)code 2456NoResolved
2017-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Total trihalomethanes (TTHM)code 2950NoResolved
2014-10-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Total trihalomethanes (TTHM)code 2950NoResolved
2014-10-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Haloacetic acids (HAA5)code 2456NoResolved
2014-07-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Total trihalomethanes (TTHM)code 2950NoResolved
2014-07-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Haloacetic acids (HAA5)code 2456NoResolved
2014-04-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Total trihalomethanes (TTHM)code 2950NoResolved

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.

City of Sunnyside: frequently asked questions

Who runs City of Sunnyside?

City of Sunnyside (PWSID WA5385400) is a community water system owned by a local government. It is regulated by the WA state drinking water program.

How many people does City of Sunnyside serve?

City of Sunnyside reports serving 17,194 people through 5,456 service connections in Yakima County, Washington.

Where does City of Sunnyside 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 City of Sunnyside have any drinking water violations?

Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in July 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 City of Sunnyside'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, none is health-based, and the most recent began in July 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the WA state drinking water program.

Where can I find City of Sunnyside's water quality report?

As a community water system, City of Sunnyside 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 Yakima County

Water systemCountyPopulation servedTypeSource
Yakima Water Division City ofYakima112,858CommunitySurface water
Nob Hill Water AssociationYakima38,050CommunityGroundwater
Grandview City ofYakima11,010CommunityGroundwater
Selah City ofYakima9,331CommunityGroundwater
Toppenish Water DepartmentYakima8,950CommunityGroundwater
Yak Co - Terrace HeightsYakima8,410CommunityGroundwater

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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, “Sunnyside City of, PWSID WA5385400, Washington”, https://aquacensus.com/water-systems/washington/sunnyside-city-of-wa5385400 (data as of October 1, 2026).