Total Haloacetic Acids (HAA5) violations in Illinois
382 active public water systems in Illinois had a Total Haloacetic Acids (HAA5) violation in the past three years, 48 of them in the latest quarter of EPA's data. What Total Haloacetic Acids (HAA5) is and why it matters.
Systems with a Total Haloacetic Acids (HAA5) violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Waukegan Waukegan · Lake County |
87,149 | 3 | 1 | |
|
O Fallon O Fallon · St. Clair County |
46,603 | 1 | 0 | |
|
Buffalo Grove Buffalo Grove · Cook County |
43,212 | 2 | 0 | |
|
Rock Island Rock Island · Rock Island County |
39,018 | 3 | 1 | |
|
Addison Addison · DuPage County |
38,017 | 1 | 0 | |
|
Northbrook Northbrook · Cook County |
34,200 | 2 | 0 | |
|
Glendale Heights Glendale Heights · DuPage County |
33,176 | 1 | 0 | |
|
Mundelein Mundelein · Lake County |
31,500 | 1 | 0 | |
|
Lansing Lansing · Cook County |
29,076 | 4 | 3 | |
|
Lake in the Hills Lake In The Hills · McHenry County |
28,661 | 1 | 0 | |
|
Wilmette Wilmette · Cook County |
27,650 | 2 | 1 | |
|
Chicago Heights Chicago Heights · Cook County |
26,184 | 2 | 0 | |
|
Woodstock Woodstock · McHenry County |
25,630 | 3 | 0 | |
|
Morton Grove Morton Grove · Cook County |
25,297 | 3 | 2 | |
|
Maywood Maywood · Cook County |
24,090 | 4 | 2 | |
|
Roselle Roselle · DuPage County |
22,897 | 2 | 0 | |
|
Crest Hill Crest Hill · Will County |
20,223 | 10 | 2 | |
|
Mokena Mokena · Will County |
19,887 | 1 | 0 | |
|
Deerfield Deerfield · Lake County |
19,196 | 3 | 1 | |
|
Shorewood Shorewood · Will County |
18,645 | 3 | 0 | |
|
Sycamore Sycamore · DeKalb County |
18,500 | 2 | 0 | |
|
Franklin Park Franklin Park · Cook County |
18,467 | 4 | 1 | |
|
Matteson Matteson · Cook County |
18,293 | 5 | 2 | |
|
Ottawa Ottawa · LaSalle County |
18,097 | 3 | 0 | |
|
Morton Morton · Tazewell County |
17,117 | 2 | 0 | |
|
Mount Vernon Mount Vernon · Jefferson County |
15,793 | 2 | 0 | |
|
Jersey Rwc Jersey County |
12,750 | 1 | 0 | |
|
Richton Park Richton Park · Cook County |
12,504 | 5 | 3 | |
|
Captain James a Lovell Fhcc Lake County |
12,100 | 6 | 2 | |
|
Robinson-Palestine Water Commission Crawford County |
11,331 | 3 | 0 | |
|
Burr Ridge Burr Ridge · DuPage County |
11,192 | 1 | 0 | |
|
Crestwood Crestwood · Cook County |
10,826 | 2 | 1 | |
|
Highland Highland · Madison County |
10,674 | 3 | 0 | |
|
Pingree Grove Hampshire · Kane County |
10,365 | 4 | 1 | |
|
Murphysboro Murphysboro · Jackson County |
10,241 | 3 | 1 | |
|
Waterloo Waterloo · Monroe County |
10,190 | 7 | 0 | |
|
Advocate Christ Medical Center Cook County |
10,000 | 5 | 1 | |
|
Sauk Village Sauk · Cook County |
9,921 | 4 | 0 | |
|
LA Salle La Salle · LaSalle County |
9,700 | 4 | 0 | |
|
Oak Brook Oak Brook · DuPage County |
9,400 | 3 | 0 | |
|
Riverside Riverside · Cook County |
9,298 | 1 | 0 | |
|
Willowbrook Willowbrook · DuPage County |
9,000 | 3 | 2 | |
|
Clear Water Service Corp Coles County |
8,900 | 2 | 0 | |
|
Lake Villa Lake Villa · Lake County |
8,829 | 1 | 0 | |
|
Calumet Park Calumet Park · Cook County |
8,442 | 3 | 2 | |
|
Benton Benton · Franklin County |
8,104 | 5 | 1 | |
|
Western Illinois University McDonough County |
8,000 | 1 | 0 | |
|
Fosterburg Pwd Madison County |
7,940 | 2 | 0 | |
|
Broadview Broadview · Cook County |
7,847 | 4 | 3 | |
|
Rock Island Arsenal, US Army Rock Island County |
7,800 | 2 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved Total Haloacetic Acids (HAA5), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Total Haloacetic Acids (HAA5) alone.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Illinois records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet.