Public water system · IL0971450

Active

Riverwoods

At a glance

Riverwoods (PWSID IL0971450) is an active community water system in Lake County, Illinois. It reports serving 3,618 people through 906 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in January 2026.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

3,618

Service connections

906

Primary source

SWP

Purchased surface water

System type

CWS

Community water system

System record

PWSIDIL0971450

System typeCommunity water system

Activity statusActive

Population served3,618

Service connections906

Primary water sourcePurchased surface water

Owner typeLocal government

Primacy agencyIL state drinking water program

City servedRiverwoods

StateIllinois

ZIP—

CountyLake County

How does Riverwoods compare with other water systems in Lake County?

By EPA's size categories, Riverwoods is a medium system (3,301 to 10,000 people). Lake County has 266 active public water systems. Its population served is about 48% above the county average of 2,442 people per system, and accounts for 0.6% of the 649,474 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 Riverwoods is about half of 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 619 Illinois systems (16%) list purchased surface water as their primary source.

Who owns and regulates Riverwoods?

EPA lists Riverwoods 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. 60 of the 266 active systems in Lake County (23%) are also owned by a local government.

Does Riverwoods have drinking water violations?

EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in January 2026. The violations listed here began between May 2003 and January 2026. By type: 6 monitoring and reporting, 1 monitoring and 1 required treatment not met. The contaminant or rule involved most often is Haloacetic acids (HAA5) (2 of them). EPA lists 6 as resolved and 2 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.

Began	Violation	Contaminant or rule	Health-based	Status
2026-01-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Haloacetic acids (HAA5)code 2456	No	Archived
2024-07-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Total trihalomethanes (TTHM)code 2950	No	Resolved
2019-11-01	MonitoringMonitoring, Routine (RTCR) · code 3A	Revised Total Coliform Rulecode 8000	No	Resolved
2019-10-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Chlorinecode 0999	No	Resolved
2016-06-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Haloacetic acids (HAA5)code 2456	No	Resolved
2016-06-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Total trihalomethanes (TTHM)code 2950	No	Resolved
2005-04-01	Required treatment not metSingle Turbidity Exceed (Enhanced SWTR) · code 43	Interim Enhanced Surface Water Treatment Rulecode 0300	Yes	Resolved
2003-05-01	Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24	Total coliform bacteria (TCR)code 3100	No	Archived

All 8 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.

Riverwoods: frequently asked questions

Who runs Riverwoods?

Riverwoods (PWSID IL0971450) is a community water system owned by a local government. It is regulated by the IL state drinking water program.

How many people does Riverwoods serve?

Riverwoods reports serving 3,618 people through 906 service connections in Lake County, Illinois.

Where does Riverwoods get its water?

EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.

Does Riverwoods have any drinking water violations?

EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in January 2026. 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 Riverwoods' 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. EPA's records list 8 violations for this system; 1 is health-based, and the most recent began in January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.

Where can I find Riverwoods' water quality report?

As a community water system, Riverwoods 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 Lake County

Water system	County	Population served	Type	Source
Waukegan	Lake	87,149	Community	Surface water
Vernon Hills - Lake Co Pw	Lake	33,207	Community	Purchased surface water
Mundelein	Lake	31,500	Community	Purchased surface water
Gurnee	Lake	30,193	Community	Purchased surface water
Highland Park	Lake	30,176	Community	Surface water
Round Lake Beach	Lake	27,200	Community	Purchased surface water

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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, “Riverwoods, PWSID IL0971450, Illinois”, https://aquacensus.com/water-systems/illinois/riverwoods-il0971450 (data as of October 1, 2026).