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Public water system · IL0990550

Active

Mendota

Community water system in LaSalle County, Illinois, drawing primarily on groundwater.

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

Population served

7,100

Service connections

2,818

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDIL0990550
System typeCommunity water system
Activity statusActive
Population served7,100
Service connections2,818
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyIL state drinking water program
City servedMendota
StateIllinois
ZIP—
CountyLaSalle County

Violations & enforcement

BeganViolationContaminant or ruleHealth-basedStatus
2025-07-02ReportingNotification, Known or Potential LSL · code 4HLead and Copper Rule Revisionscode 5200NoResolved
2025-07-01Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72Consumer Confidence Rulecode 7000NoResolved
2025-07-01Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52Lead and Copper Rulecode 5000NoResolved
2021-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Haloacetic acids (HAA5)code 2456YesResolved
2020-10-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Haloacetic acids (HAA5)code 2456YesResolved
2020-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Haloacetic acids (HAA5)code 2456YesResolved
2008-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Combined Radium (-226 and -228)code 4010YesResolved
2007-10-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Combined Radium (-226 and -228)code 4010YesResolved
2007-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Combined Radium (-226 and -228)code 4010YesResolved
2007-04-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Combined Radium (-226 and -228)code 4010YesResolved
2007-01-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Combined Radium (-226 and -228)code 4010YesResolved
2006-10-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02Combined Radium (-226 and -228)code 4010YesResolved

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.

Mendota: frequently asked questions

Is Mendota's water safe to drink?

Mendota is an active community water system regulated under the Safe Drinking Water Act, overseen by the IL state drinking water program. EPA's SDWA data records violations for this system — the most recent are listed on this page, including health-based violations; consult EPA ECHO or your annual Consumer Confidence Report for its current compliance status.

Who runs Mendota?

Mendota (PWSID IL0990550) is a local government-owned community water system, regulated by the IL state drinking water program.

How many people does Mendota serve?

Mendota reports serving 7,100 people through 2,818 service connections in LaSalle County, Illinois.

Where does Mendota get its water?

EPA SDWIS lists this system's primary water source as groundwater.

Other water systems in LaSalle County

Water systemCountyPopulation servedTypeSource
Il American-StreatorLaSalle19,000CommunitySurface water
OttawaLaSalle18,097CommunityGroundwater
PeruLaSalle10,300CommunityGroundwater
La SalleLaSalle9,700CommunityGroundwater
MarseillesLaSalle5,061CommunityGroundwater
Prairie Path Water Company-Lake HolidayLaSalle4,750CommunityGroundwater

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