American Bottoms Regional WWTP 
Argenta Sanitary District
Bloomington and Normal WRD 
City of Effingham 
City of Elmhurst 
City of Joliet
City of LaSalle  
City of Moline  
City of Naperville 
City of Rock Island
City of St. Charles
City of Sterling
City of Wood Dale
Clinton Sanitary District 
Danville Sanitary District 
Dekalb Sanitary District 
Downers Grove Sanitary District 
Du Page County - Dept. of Public Works
Flagg Creek Water Reclamation District
Fox Metro Water Recl. Dist  
Fox River Water Reclamation District
Glenbard Wastewater Authority 
Greater Peoria Sanitary District 
Illinois American Water Company
Kankakee River Metropolitan Agency 
LaGrange Highlands Sanitary District  
Lake County Public Works Department 
Lake in the Hills Sanitary District 
Lakes Region Sanitary District
Metro. Water Reclamation Dist/Chicago  
Mill Creek Water Reclamation District
Mission Brook Sanitary District 
Northern Moraine Wastewater Reclamation Dist.
Northwest Regional Treatment Plant (Fox Lake) 
Rock River Water Recl District 
Sanitary District of Decatur
Salt Creek Sanitary District  
South Lyons Township Sant Dist  
South Stickney Sanitary Dist  
Springfield Metro San Dist 
The Galesburg Sanitary District 
The North Shore Sanitary District
Thorn Creek Basin Sanitary District
Urbana & Champaign Sanitary District 
Village of Bartlett
Village of Bloomingdale
Village of Deerfield
Village of Hanover Park
Village of Itasca
Village of Lena
Village of Plainfield
Village of Roselle
Westville/Belgium Sanitary District
Wheaton Sanitary District
Yorkville-Bristol Sanitary District