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Public water system · IL1310450

Active

Viola

At a glance

Viola (PWSID IL1310450) is an active community water system in Mercer County, Illinois. It reports serving 970 people through 458 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 October 2025.

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

Population served

970

Service connections

458

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDIL1310450
System typeCommunity water system
Activity statusActive
Population served970
Service connections458
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyIL state drinking water program
City servedViola
StateIllinois
ZIP—
CountyMercer County

How does Viola compare with other water systems in Mercer County?

By EPA's size categories, Viola is a small system (501 to 3,300 people). Mercer County has 27 active public water systems, and Viola is the 2nd-largest of them by population served. Its population served is about 128% above the county average of 426 people per system, and accounts for 8.4% of the 11,499 people reported by systems filed under the county. Across Illinois, the 3,872 active systems average 3,204 people each. Nationally, the average active community water system reports serving 6,703 people, so Viola 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. Illinois has 1,773 active community water systems, 46% of the state's 3,872 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,808 Illinois systems (73%) list groundwater as their primary source.

Who owns and regulates Viola?

EPA lists Viola as owned by a local government. The IL state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 10 of the 27 active systems in Mercer County (37%) are also owned by a local government.

Does Viola have drinking water violations?

Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in October 2025. The violations listed here began between November 2006 and October 2025. By type: 9 public notice, recordkeeping or other and 3 monitoring and reporting. The contaminant or rule involved most often is Public Notice (5 of them). EPA lists 11 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
2025-10-12Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75Public Noticecode 7500NoResolved
2023-01-01Monitoring and reportingMonitoring, Regular · code 03Toxaphenecode 2020NoArchived
2012-11-15Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75Public Noticecode 7500NoResolved
2012-11-15Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75Public Noticecode 7500NoResolved
2011-10-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Chlorinecode 0999NoResolved
2011-10-01Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24Total coliform bacteria (TCR)code 3100NoResolved
2010-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2009-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2008-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2007-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2006-11-04Public notice, recordkeeping or otherPublic Notification Violation without NPDWR Violation · code 76Public Noticecode 7500NoResolved
2006-11-04Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75Public Noticecode 7500NoResolved

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.

Viola: frequently asked questions

Who runs Viola?

Viola (PWSID IL1310450) is a community water system owned by a local government. It is regulated by the IL state drinking water program.

How many people does Viola serve?

Viola reports serving 970 people through 458 service connections in Mercer County, Illinois.

Where does Viola 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 Viola 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 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 Viola'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 October 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.

Where can I find Viola's water quality report?

As a community water system, Viola 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 Mercer County

Water systemCountyPopulation servedTypeSource
AledoMercer3,470CommunityGroundwater
SherrardMercer785CommunityGroundwater
Fyre Lake Water CompanyMercer760CommunityGroundwater
KeithsburgMercer747CommunityGroundwater
New WindsorMercer740CommunityGroundwater
MathervilleMercer651CommunityGroundwater

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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, “Viola, PWSID IL1310450, Illinois”, https://aquacensus.com/water-systems/illinois/viola-il1310450 (data as of October 1, 2026).