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Public water system · IL0990300

Active

La Salle

At a glance

La Salle (PWSID IL0990300) is an active community water system in LaSalle County, Illinois. It reports serving 9,700 people through 3,967 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, 6 are health-based, and the most recent began in October 2025.

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

Population served

9,700

Service connections

3,967

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDIL0990300
System typeCommunity water system
Activity statusActive
Population served9,700
Service connections3,967
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyIL state drinking water program
City servedLa Salle
StateIllinois
ZIP—
CountyLaSalle County

How does La Salle compare with other water systems in LaSalle County?

By EPA's size categories, La Salle is a medium system (3,301 to 10,000 people). LaSalle County has 129 active public water systems, and La Salle is the 4th-largest of them by population served. Its population served is about 12 times the county average of 816 people per system, and accounts for 9.2% of the 105,319 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 La Salle is about 45% 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. 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 La Salle?

EPA lists La Salle 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. 20 of the 129 active systems in LaSalle County (16%) are also owned by a local government.

Does La Salle have drinking water violations?

Of the 12 most recent violations in EPA's records, 6 are health-based, and the most recent began in October 2025. The violations listed here began between July 2007 and October 2025. By type: 6 contaminant level above the legal limit, 5 monitoring and reporting and 1 monitoring. The contaminant or rule involved most often is Total trihalomethanes (TTHM) (6 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
2025-10-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Haloacetic acids (HAA5)code 2456NoArchived
2024-06-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2024-04-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Chlorinecode 0999NoResolved
2023-10-01Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52Lead and Copper Rulecode 5000NoResolved
2022-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Total trihalomethanes (TTHM)code 2950YesResolved
2022-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Total trihalomethanes (TTHM)code 2950YesResolved
2022-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Total trihalomethanes (TTHM)code 2950YesResolved
2017-10-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Total trihalomethanes (TTHM)code 2950YesResolved
2017-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Total trihalomethanes (TTHM)code 2950YesResolved
2017-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Total trihalomethanes (TTHM)code 2950YesResolved
2013-04-01Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26Total coliform bacteria (TCR)code 3100NoResolved
2007-07-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Bromatecode 1011NoResolved

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.

La Salle: frequently asked questions

Who runs La Salle?

La Salle (PWSID IL0990300) is a community water system owned by a local government. It is regulated by the IL state drinking water program.

How many people does La Salle serve?

La Salle reports serving 9,700 people through 3,967 service connections in LaSalle County, Illinois.

Where does La Salle 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 La Salle have any drinking water violations?

Of the 12 most recent violations in EPA's records, 6 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 La Salle'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, 6 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 IL state drinking water program.

Where can I find La Salle's water quality report?

As a community water system, La Salle 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 LaSalle County

Water systemCountyPopulation servedTypeSource
Il American-StreatorLaSalle19,000CommunitySurface water
OttawaLaSalle18,097CommunityGroundwater
PeruLaSalle10,300CommunityGroundwater
MendotaLaSalle7,100CommunityGroundwater
MarseillesLaSalle5,061CommunityGroundwater
Prairie Path Water Company-Lake HolidayLaSalle4,750CommunityGroundwater

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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, “La Salle, PWSID IL0990300, Illinois”, https://aquacensus.com/water-systems/illinois/la-salle-il0990300 (data as of October 1, 2026).