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Community Water System · PWS IL0970800

Lake Forest

Operator location Lake Forest, Illinois - larger served population (> 3,309) at 19,642 people served; 33 SDWIS violations on record from surface water sources.

19,642
People served (this PWS)
33
EPA violations (this PWS)
2
Health-based (this PWS)
No PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Lake Forest standing, mid SDWIS violation third

19,642 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 6% is middle-third health share (≤ 23%). UCMR5: UCMR5 tested, none detected. Population rank #2,757 of 29,740 among systems serving 500+.

The verdict

Lake Forest lands in the middle third by violation volume (33), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is large (19,642; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 6% (middle-third health share (≤ 23%)). UCMR5 tested this system and reported no PFAS above the minimum reporting level.

#2,757 of 29,740
Population · /systems
#128 of 1,310
Population · IL
33
Total EPA violations on record
6%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

System Details

System Type
Community
Owner Type
Local
Connections
6,925
County
Lake
School/Daycare
No
MCL Violations
0
Monitoring Violations
17
Treatment Tech Violations
2

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
CARBON, TOTAL MR 4 2004
TTHM MR 4 2019
Total Haloacetic Acids (HAA5) MR 4 2019
Lead and Copper Rule MR 4 2023
Consumer Confidence Rule Other 2 2017
Lead and Copper Rule TT 2 1994
Gross Alpha, Excl. Radon and U MR 1 1977

Violation Count vs. the National Corpus

Lake Forest has 33 recorded EPA violations, 45% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 54% carry more. 6% of this system's own violations are health-based (2 of 33), and it ranks #2,757 of 29,740 by population served among that same cohort.

EPA violations vs. the national water-system corpus

Public water systems serving 500+ people (EPA SDWIS)

33 Lower than most fewer violations than 54% of 29,740 water systems

the national water-system corpus, bucketed by value

Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.

Source EPA SDWIS · 2026-05-15

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
4:2 FTS 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
NFDHA 8/21/2023 <20.00 ppt 20.00 ppt Not Detected
8:2 FTS 8/21/2023 <5.00 ppt 5.00 ppt Not Detected
PFMPA 8/21/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFEESA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeS 8/21/2023 <4.00 ppt 4.00 ppt Not Detected
PFHpS 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 8/21/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 8/21/2023 <7.00 ppt 7.00 ppt Not Detected
NMeFOSAA 8/21/2023 <6.00 ppt 6.00 ppt Not Detected
6:2 FTS 8/21/2023 <5.00 ppt 5.00 ppt Not Detected
NEtFOSAA 8/21/2023 <5.00 ppt 5.00 ppt Not Detected
PFHxS 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFBA 8/21/2023 <5.00 ppt 5.00 ppt Not Detected
PFBS 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 8/21/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 8/21/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 8/21/2023 <4.00 ppt 4.00 ppt Not Detected
PFDA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 8/21/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 8/21/2023 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 8/21/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 8/21/2023 <2.00 ppt 2.00 ppt Not Detected
PFDoA 8/21/2023 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 5/6/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 5/6/2024 <6.00 ppt 6.00 ppt Not Detected
9Cl-PF3ONS 5/6/2024 <2.00 ppt 2.00 ppt Not Detected
PFTA 5/6/2024 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 5/6/2024 <7.00 ppt 7.00 ppt Not Detected
HFPO-DA 5/6/2024 <5.00 ppt 5.00 ppt Not Detected
PFEESA 5/6/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 5/6/2024 <3.00 ppt 3.00 ppt Not Detected
NFDHA 5/6/2024 <20.00 ppt 20.00 ppt Not Detected
PFPeS 5/6/2024 <4.00 ppt 4.00 ppt Not Detected
PFHpS 5/6/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeA 5/6/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 5/6/2024 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 5/6/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 5/6/2024 <3.00 ppt 3.00 ppt Not Detected
PFUnA 5/6/2024 <2.00 ppt 2.00 ppt Not Detected
PFBA 5/6/2024 <5.00 ppt 5.00 ppt Not Detected
ADONA 5/6/2024 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 5/6/2024 <5.00 ppt 5.00 ppt Not Detected
PFHxA 5/6/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 5/6/2024 <3.00 ppt 3.00 ppt Not Detected

Population served record for Lake Forest

EPA SDWIS lists 19,642 people served and 6,925 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS · Illinois EPA, Bureau of Water

Nationwide peers

33 violations · 19,642 served: nearest cross-state SDWIS matches.

What to do with Lake Forest

Use this system's EPA-reported record as a starting filter, not a final verdict.

  • See how every tracked system in Illinois compares on the same EPA violation measures. Illinois systems
  • Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
  • Find and compare another public water system by name or PWSID. Search systems

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater