Tapcensus

Illinois

Cook County drinking water quality

423 active public water systems serve 5,279,874 people in Cook County. 203 are compliant, 220 had at least one EPA violation in the past three years, 43 are designated serious violators, and 5 carry a health flag.

Active systems 423 163 community systems
People served 5.3M by public water systems
Systems with violations 220 52% of active systems, past 3 years
Serious violators 43 5 systems carry a health flag

Needs attention

Richton Park IL0312550 · Richton Park · Community water system · Serves 12,504 5 rules violated in the past three years. Unresolved: Lead and Copper Rule, Public Notice Rule and Revised PN Rule, and Consumer Confidence Rule.
Robbins IL0312700 · Robbins · Community water system · Serves 5,415 6 rules violated in the past three years. Unresolved: Lead and Copper Rule, Public Notice Rule and Revised PN Rule, and Consumer Confidence Rule.
Lutheran General Hospital IL3154633 · Non-Transient non-community system · Serves 3,400 6 rules violated in the past three years. Unresolved: Public Notice Rule and Revised PN Rule.
Dixmoor IL0310660 · Dixmoor · Community water system · Serves 2,973 5 rules violated in the past three years. Unresolved: Lead and Copper Rule, Lead and Copper Rule Revisions, Public Notice Rule and Revised PN Rule, and Consumer Confidence Rule.
Prospect Heights Plaza IL3161463 · Non-Transient non-community system · Serves 1,240 6 rules violated in the past three years. Unresolved: Lead and Copper Rule and Public Notice Rule and Revised PN Rule.
Swedish Covenant Hospital IL3162651 · Non-Transient non-community system · Serves 1,200 6 rules violated in the past three years. Unresolved: Public Notice Rule and Revised PN Rule.
JW Marriot Hotel IL3156836 · Non-Transient non-community system · Serves 700 4 rules violated in the past three years. Unresolved: Lead and Copper Rule and Public Notice Rule and Revised PN Rule.
Schiller Woods W 3072 IL3074484 · Transient non-community system · Serves 400 3 rules violated in the past three years. Unresolved: Public Notice Rule and Revised PN Rule.
Crabtree Nature Center IL3100354 · Transient non-community system · Serves 273 3 rules violated in the past three years. Unresolved: Public Notice Rule and Revised PN Rule.
Swallow Cliff Stairs Pavillion 5022 IL3101980 · Transient non-community system · Serves 200 3 rules violated in the past three years. Unresolved: Public Notice Rule and Revised PN Rule.

37 more systems with a serious violator or health flag designation are in the lists below.

Community water systems

163 systems, largest first
SystemServesStatusRules violated, 3 yrUnresolved
Weatherstone Lakes MHP
Sauk 		190 0 0
Aqua Illinois-Summerdale
Norridge 		145 2 0
IL American-Midwest Palos
 126 0 0
Sunrise Senior Living
Prospect Heights 		82 1 0
Edward Hines JR V a Hospital
 60 2 0
Mid-Mark Water Commission
 25 0 0
Broadview-Westchester Joint Water Agency
Broadview 		1 0 0
Brookfield-North Riverside Water Comm.
Brookfield 		1 0 0
Hillside Berkeley Water Commission
Bellwood 		1 0 0
Northwest Suburban Municipal Jawa
 1 0 0
Northwest Water Commission
Des Plaines 		1 0 0
IL American-Lake Water Company
 0 0 0
Morton Grove Niles Water Commission
Niles 		0 0 0
Non-community systems (260: schools, campgrounds, workplaces, restaurants)

These systems serve places people visit rather than homes.

SystemServesStatusRules violated, 3 yrUnresolved
Advocate Christ Medical Center
 10,000 5 1
Northshore University Evanston
 6,300 4 1
U of I Chicago Medical Center
 5,000 4 1
Lutheran General Hospital
 3,400 6 1
Northshore Univ Glenbrook
 3,200 4 1
Northshore University Skokie
 2,500 4 1
Prospect Heights Plaza
 1,240 6 2
Swedish Covenant Hospital
 1,200 6 1
Franciscan Health Olympia Fields
 1,050 2 0
Alexian Brothers Medical Center
 1,000 0 0
Alexian Brothers Medical Center & Rehab
 1,000 0 0
Aldi #92
 821 0 0
Lucky Monk
 736 0 0
JW Marriot Hotel
 700 4 2
Metro Prep School
 690 0 0
Cbre West Plaza
 600 1 0
Old Willow Complex
 520 0 0
Citgo Dunkin Donuts Prospect Heights
 507 2 0
Coghill Golf Courses #2&4
 400 0 0
Insight Hospital and Medical Center Chic
 400 1 0
Schiller Woods 3070
 400 3 1
Schiller Woods 3102
 400 3 1
Schiller Woods W 3072
 400 3 1
ST Mary's Slovenian Catholic Center
 400 0 0
Zen Leaf
 369 0 0
Marquette Building
 360 0 0
Central Galilee United Methodist Church
 350 2 0
Convenient Plaza Hot Bread
 350 0 0
Cog Hill Country Club
 340 3 1
The Forge: Lemont Quarries
 305 2 0
Crabtree Nature Center
 273 3 1
Bar Salotto
 265 3 1
Safari Life Before & After School Center
 250 2 1
Monte Carlo Plaza
 235 3 1
Countryside School
 225 3 0
Maranatha Bible Church
 213 3 0
Amc Theaters
 206 0 0
Chicago Hts Moose Lodge 828
 200 0 0
Decoma Day Camp
 200 2 1
Korner House Restaurant & Lounge
 200 0 0
South Barrington Park District
 200 0 0
ST Mary Coptic Church
 200 3 1
Swallow Cliff Stairs Pavillion 5022
 200 3 1
Lynwood Sports Center
 175 0 0
Prospect Heights Comm Church
 175 0 0
600 Waukegan Road
 170 4 1
Saps Temple
 166 1 0
Camp Shabbona Woods
 153 3 1
Barbara Rose Elementary School
 150 2 0
Brandt's of Palatine
 150 0 0
South Barrington Partners, LLC
 121 5 0
Grace Evang Lutheran Church
 115 0 0
Imtt Illinois LLC Lemont
 110 6 2
Willow Hill Golf Course
 106 2 0
Angelo Caputo's Fresh Markets
 100 0 0
Bunker Hill 2099
 100 3 1
Camp Palos Troop House Rbns Ldge
 100 2 0
Cosman Bike Trail 1249
 100 3 1
Deer Grove South HP 1138
 100 3 1
Deer Grove West HP 1014
 100 3 1
Donkey Inn Bar and Grill
 100 3 1
Harm Woods North
 100 3 1
Jewel 2363
 100 0 0
Jewel 86
 100 0 0
Lola's Pizza
 100 1 0
Marianos Park Ridge
 100 0 0
MC Donalds Rest 302
 100 1 0
Moms Organic Market #1607
 100 0 0
Nachos Pizza
 100 2 1
Rand/olive Condominium Building
 100 2 1
T's Bar and Grill
 100 0 0
Thorton's Gas Station
 100 4 0
Whole Foods Market #1006
 100 0 0
Whole Foods Market #1008
 100 0 0
Whole Foods Market #1029
 100 0 0
Whole Foods Market #410 Sauganash
 100 0 0
Whole Foods Market #413
 100 0 0
Whole Foods Market #425 Halsted
 100 0 0
Whole Foods Market #439 One Chicago
 100 0 0
Whole Foods Market 1077 Downtown Evans
 100 0 0
Joeys Pizza
 80 1 0
Sofia's Video Gaming
 80 0 0
Camp Bullfrog
 62 3 1
Jewel Food Store #3291
 60 0 0
Masjid AL Huda
 60 2 1
Cci Manufacturing
 57 5 0
Camp Palos Cluster Cabin WS Hse
 50 3 0
Camp Palos Ranch House
 50 2 0
Camp Palos Rustic Cabin Bnk HS
 50 2 0
Lemont HS Sports Complex
 50 2 0
Shalom Memorial Park
 50 3 1
The Crave Bar
 50 3 1
Wellbrand Properties, LLC
 50 3 1
Northbrook Montessori School
 48 3 0
Heritage Environmental
 45 2 0
Flower Garden Day Care 3rd Bld
 40 5 1
Flower Garden Annex
 38 6 2
1st Church of the Nazarene
 30 0 0
Assumption Cemetary
 30 3 0
Jewel 2508 W Howard
 30 0 0
All 260 in the systems table
Inactive systems (2,682, no longer operating or reporting)

Kept for the record and excluded from the county totals above. Browse inactive systems.

About this data

Totals cover active systems. Systems serving more than one county are counted in each county. EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several.

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.