Skip to content
AquaCensus

Public water system · IL1110950

Active

Woodstock

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

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

Population served

25,630

Service connections

8,995

Primary source

GW

Groundwater

System type

CWS

Community water system

System record

PWSIDIL1110950
System typeCommunity water system
Activity statusActive
Population served25,630
Service connections8,995
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyIL state drinking water program
City servedWoodstock
StateIllinois
ZIP—
CountyMcHenry County

Violations & enforcement

BeganViolationContaminant or ruleHealth-basedStatus
2025-03-05Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75Public Noticecode 7500NoResolved
2025-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Haloacetic acids (HAA5)code 2456NoResolved
2025-01-01Monitoring and reportingMonitoring and Reporting (DBP) · code 27Total trihalomethanes (TTHM)code 2950NoResolved
2024-04-02Required treatment not metOCCT/SOWT Study/Recommendation · code 57Lead and Copper Rulecode 5000YesResolved
1997-01-01Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52Lead and Copper Rulecode 5000NoResolved
1996-08-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesArchived
1996-08-01Monitoring and reportingMonitoring, Repeat Major (TCR) · code 25Total coliform bacteria (TCR)code 3100NoArchived
1992-12-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21Total coliform bacteria (TCR)code 3100YesArchived
1991-02-01Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24Total coliform bacteria (TCR)code 3100NoArchived
1977-06-30Monitoring and reportingMonitoring, Regular · code 03Gross alpha (excluding radon and uranium)code 4000NoArchived

All 10 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.

Woodstock: frequently asked questions

Is Woodstock's water safe to drink?

Woodstock 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 Woodstock?

Woodstock (PWSID IL1110950) is a local government-owned community water system, regulated by the IL state drinking water program.

How many people does Woodstock serve?

Woodstock reports serving 25,630 people through 8,995 service connections in McHenry County, Illinois.

Where does Woodstock get its water?

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

Other water systems in McHenry County

Water systemCountyPopulation servedTypeSource
Crystal LakeMcHenry40,661CommunityGroundwater
AlgonquinMcHenry30,700CommunityGroundwater
Lake in the HillsMcHenry28,661CommunityGroundwater
HuntleyMcHenry28,495CommunityGroundwater
MchenryMcHenry22,335CommunityGroundwater
CaryMcHenry17,826CommunityGroundwater

Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.