How many public water systems are in Indiana?

Indiana has 3,975 active public water systems in EPA SDWIS records, including 774 community water systems. Together they report serving 5.8M people.

What is the largest water system in Indiana?

Citizens Water - Indianapolis is the largest active public water system in Indiana, serving a reported 880,345 people.

Does Indiana rely more on groundwater or surface water?

97.2% of Indiana's active public water systems draw primarily on groundwater and 2.8% on surface water (including purchased supplies).

Indiana public water systems

3,975 active systems regulated under the Safe Drinking Water Act, serving a reported 5.8M people across 109 counties.

Dataset updated July 2026 . Source: EPA SDWIS/ECHO, refreshed quarterly.

Active systems

3,975

Population served

5.8M

Community systems

774

Groundwater share

97.2%

System types in Indiana

774

Community water system

601

Non-transient non-community water system

2,600

Transient non-community water system

Largest water systems in Indiana

The largest active public water systems in Indiana by population served
#	Water system	County	Population served	Type	Source
1	Citizens Water - Indianapolis	Marion	880,345	Community	Surface water
2	Fort Wayne - 3 Rivers Filtration Plant	Allen	269,994	Community	Surface water
3	Indiana American Water - Northwest	Lake	210,510	Community	Surface water
4	Evansville Water Utility	Vanderburgh	182,444	Community	Surface water
5	South Bend Water Works	St. Joseph	115,000	Community	Groundwater
6	Indiana American Water - S. Indiana	Clark	104,445	Community	Groundwater
7	Carmel Water Department	Hamilton	99,927	Community	Groundwater under influence of surface water
8	Indiana American Water - Johnson County	Johnson	86,813	Community	Groundwater
9	City of Bloomington Utilities	Monroe	83,000	Community	Surface water
10	Hammond Water Works Department	Lake	78,384	Community	Surface water
11	Indiana American Water - Muncie	Delaware	74,030	Community	Surface water
12	Lafayette Water Works	Tippecanoe	70,835	Community	Groundwater
13	Indiana American Water - Terre Haute	Vigo	67,765	Community	Groundwater
14	Citizens Water of Westfield, LLC	Hamilton	61,493	Community	Groundwater
15	Indiana American Water - Kokomo	Howard	59,313	Community	Surface water
16	Anderson Water Department	Madison	55,212	Community	Groundwater under influence of surface water
17	Columbus Municipal Utility	Bartholomew	51,122	Community	Groundwater
18	Purdue Univ. Water Works	Tippecanoe	50,000	Community	Groundwater
19	Mishawaka Utilities	St. Joseph	49,675	Community	Groundwater
20	City of Lawrence Utilities	Marion	49,000	Community	Groundwater
21	Elkhart Public Works and Utilities	Elkhart	46,455	Community	Groundwater
22	Indiana American Water - Noblesville	Hamilton	45,575	Community	Groundwater
23	Indiana American Water - Richmond	Wayne	41,485	Community	Surface water
24	Valparaiso Department of Water Works	Porter	36,000	Community	Groundwater
25	Indiana American Water - West Lafayette	Tippecanoe	35,533	Community	Groundwater

By county

Kosciusko297 systems Elkhart285 systems St. Joseph222 systems LaGrange211 systems Steuben145 systems LaPorte126 systems Lake108 systems Noble102 systems Allen91 systems Tippecanoe89 systems Marshall85 systems Porter81 systems White78 systems Adams74 systems Hamilton67 systems Jasper65 systems Miami65 systems Delaware63 systems Hancock60 systems Wayne59 systems Henry58 systems Marion56 systems Hendricks54 systems Wabash50 systems Cass48 systems DeKalb48 systems Madison48 systems Montgomery48 systems Grant47 systems Starke46 systems Howard44 systems Randolph44 systems Carroll40 systems Whitley40 systems Newton39 systems Shelby38 systems Fulton33 systems Johnson33 systems Parke33 systems Clinton32 systems Huntington32 systems Pulaski32 systems Jay31 systems Boone30 systems Vigo29 systems Rush27 systems Putnam25 systems Wells25 systems Morgan23 systems Warren23 systems Owen20 systems Fountain18 systems Knox18 systems Decatur17 systems Tipton16 systems Vermillion16 systems Bartholomew15 systems Clay15 systems Spencer15 systems Union14 systems Sullivan13 systems Gibson12 systems Clark11 systems Franklin11 systems Jefferson11 systems Monroe11 systems Dubois11 systems Dearborn10 systems Fayette10 systems Jackson10 systems Jennings10 systems Ripley10 systems Warrick10 systems Posey9 systems Benton8 systems Blackford8 systems Daviess8 systems Greene8 systems Harrison8 systems Washington8 systems Brown6 systems Orange6 systems Switzerland6 systems Vanderburgh6 systems Crawford6 systems Lawrence6 systems Perry6 systems Pike6 systems Martin5 systems Floyd4 systems Will3 systems Ohio3 systems Darke3 systems

Scott2 systems

Berrien2 systems

Branch2 systems

Boise1 systems

Iroquois1 systems

Arenac1 systems

Wexford1 systems

Washtenaw1 systems

Kalamazoo1 systems

Allegan1 systems

Beltrami1 systems

Churchill1 systems

Paulding1 systems

Portage1 systems

Mercer1 systems

Bailey1 systems