Public water system · IL0970800
ActiveLake Forest
At a glance
Lake Forest (PWSID IL0970800) is an active community water system in Lake County, Illinois. It reports serving 19,642 people through 6,925 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. EPA's records list 8 violations for this system; 2 are health-based, and the most recent began in October 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
19,642
Service connections
6,925
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Lake Forest compare with other water systems in Lake County?
By EPA's size categories, Lake Forest is a large system (10,001 to 100,000 people). Lake County has 266 active public water systems. Its population served is about 8 times the county average of 2,442 people per system, and accounts for 3% 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 Lake Forest is about 193% 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. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 89 Illinois systems (2.3%) list surface water as their primary source.
Who owns and regulates Lake Forest?
EPA lists Lake Forest 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 Lake Forest have drinking water violations?
EPA's records list 8 violations for this system; 2 are health-based, and the most recent began in October 2023. The violations listed here began between June 1977 and October 2023. By type: 5 monitoring and reporting, 2 required treatment not met and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Lead and Copper Rule (3 of them). EPA lists 7 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.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2023-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2019-02-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2019-02-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2017-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Inadequate Reporting · code 72 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2004-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Resolved |
| 1994-01-01 | Required treatment not metPublic Education · code 65 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 1992-12-07 | Required treatment not metOCCT/SOWT Study/Recommendation · code 57 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 1977-06-30 | Monitoring and reportingMonitoring, Regular · code 03 | Gross alpha (excluding radon and uranium)code 4000 | 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.
Lake Forest: frequently asked questions
Who runs Lake Forest?
Lake Forest (PWSID IL0970800) is a community water system owned by a local government. It is regulated by the IL state drinking water program.
How many people does Lake Forest serve?
Lake Forest reports serving 19,642 people through 6,925 service connections in Lake County, Illinois.
Where does Lake Forest get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Lake Forest have any drinking water violations?
EPA's records list 8 violations for this system; 2 are health-based, and the most recent began in October 2023. 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 Lake Forest'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. EPA's records list 8 violations for this system; 2 are health-based, and the most recent began in October 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the IL state drinking water program.
Where can I find Lake Forest's water quality report?
As a community water system, Lake Forest 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 |
Related pages
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.
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, “Lake Forest, PWSID IL0970800, Illinois”, https://aquacensus.com/water-systems/illinois/lake-forest-il0970800 (data as of October 1, 2026).