IL / Lake Forest
IL · Tap water records
Lake Forest tap water, in plain English
Here is what the EPA's own data shows about tap water in Lake Forest. According to EPA SDWIS data retrieved June 2026, Lake Forest is served by 3 active community water systems, together reported to serve about 19,762 people.
As of June 2026, EPA records show 52 violations across the community water system(s) serving Lake Forest, going back to the earliest EPA record. 10 of these are classified by the EPA as health-based (a contaminant recorded above the limit the EPA tracks); the rest are monitoring or reporting violations. Each is listed by system below, with its status.
What the EPA has on record, by system
Lake Forest
19,642 served · surface water · PWSID IL0970800 - Health-based CARBON, TOTAL: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times in July 2024. The EPA record for these does not include a measured level. EPA records do not show all of these as returned to compliance.
- Health-based Lead and Copper Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between December 1992 and January 1994. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
- Monitoring Orthophosphate: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in July 2025. EPA records do not show all of these as returned to compliance.
- Monitoring pH: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in July 2025. EPA records do not show all of these as returned to compliance.
- Monitoring Alkalinity, Total: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in July 2025. EPA records do not show all of these as returned to compliance.
- Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 4 times in October 2023. All have since returned to compliance, per EPA records.
- Monitoring TTHM: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in February 2019. All have since returned to compliance, per EPA records.
- Monitoring Total Haloacetic Acids (HAA5): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in February 2019. All have since returned to compliance, per EPA records.
- Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 2 times in July 2017. All have since returned to compliance, per EPA records.
Ottawa Estates Mhp (Formerly Dattis Mhp)
70 served · groundwater · PWSID IL0995225 - Health-based Lead and Copper Rule: a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 3 times between January 1995 and January 1998. The EPA record for these does not include a measured level. All have since returned to compliance, per EPA records.
- Monitoring Lead and Copper Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in December 2017. All have since returned to compliance, per EPA records.
- Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in December 2008. All have since returned to compliance, per EPA records.
Elm Oak Mutual Water System
50 served · groundwater · PWSID IL0975736 - Health-based Combined Radium (-226 and -228): a health-based violation (a contaminant recorded above the limit the EPA tracks), recorded 2 times between July 2019 and October 2019. The EPA record lists a level of 8 PCI/L; the limit (MCL) is 5 PCI/L. All have since returned to compliance, per EPA records.
- Monitoring Public Notice: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 8 times between July 2006 and February 2024. All have since returned to compliance, per EPA records.
- Monitoring Combined Radium (-226 and -228): a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 6 times between January 2019 and January 2020. EPA records do not show all of these as returned to compliance.
- Monitoring Gross Alpha Particle Activity: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded 6 times between January 2019 and January 2020. EPA records do not show all of these as returned to compliance.
- Monitoring Combined Uranium: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2019. All have since returned to compliance, per EPA records.
- Monitoring Revised Total Coliform Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in June 2018. All have since returned to compliance, per EPA records.
- Monitoring Chlorine: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in April 2018. All have since returned to compliance, per EPA records.
- Monitoring Consumer Confidence Rule: a monitoring or reporting violation (a required test or report was late or missed — not a measured exceedance), recorded once in July 2012. All have since returned to compliance, per EPA records.
What this means
A health-based violation means a contaminant was recorded above the limit the EPA tracks for it. A monitoring or reporting violation means a required test or report was late or missed — not that a contaminant was measured above a limit. “Returned to compliance” means the EPA recorded the issue as resolved.
This page summarizes the EPA's own records and does not assess whether your water is safe to drink. For the most current details, you can verify every record directly with the EPA, and contact your water system with questions.
Source: U.S. EPA Envirofacts SDWIS, retrieved June 2026. Records cover the EPA's full reporting history for these systems. Verify at EPA ECHO.