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Public water system · IL0312520

Active

Posen

Community water system in Cook County, Illinois, drawing primarily on purchased surface water.

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

Population served

5,331

Service connections

1,754

Primary source

SWP

Purchased surface water

System type

CWS

Community water system

System record

PWSIDIL0312520
System typeCommunity water system
Activity statusActive
Population served5,331
Service connections1,754
Primary water sourcePurchased surface water
Owner typeLocal government
Primacy agencyIL state drinking water program
City servedPosen
StateIllinois
ZIP—
CountyCook 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 7000NoUnaddressed
2020-12-30Monitoring and reportingLead Consumer Notice · code 66Lead and Copper Rulecode 5000NoResolved
2017-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2014-07-01Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72Consumer Confidence Rulecode 7000NoResolved
2014-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Haloacetic acids (HAA5)code 2456NoResolved
2014-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Total trihalomethanes (TTHM)code 2950NoResolved
2013-06-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2012-07-01Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71Consumer Confidence Rulecode 7000NoResolved
2007-07-01Monitoring and reportingWater Quality Parameter M/R · code 53Lead and Copper Rulecode 5000NoResolved
2004-07-01Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72Consumer Confidence Rulecode 7000NoResolved
2002-10-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoArchived

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.

Posen: frequently asked questions

Is Posen's water safe to drink?

Posen 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 Posen?

Posen (PWSID IL0312520) is a local government-owned community water system, regulated by the IL state drinking water program.

How many people does Posen serve?

Posen reports serving 5,331 people through 1,754 service connections in Cook County, Illinois.

Where does Posen get its water?

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

Other water systems in Cook County

Water systemCountyPopulation servedTypeSource
ChicagoCook2,721,308CommunitySurface water
CiceroCook83,000CommunityPurchased surface water
SchaumburgCook75,750CommunityPurchased surface water
EvanstonCook74,486CommunitySurface water
Arlington HeightsCook73,320CommunityPurchased surface water
PalatineCook70,875CommunityPurchased surface water

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