| Mount Union City Of (russ) | Mount Union | 0.0038 |
| City Of Spragueville STP | Spragueville | 0.0035 |
| Bevington City Of STP | Bevington | 0.0033 |
| Greenville, City Of STP | Greenville | 0.0031 |
| Watkins, Community Of | Watkins | 0.002 |
| City Of Rinard WTP | Rinard | 0.0018 |
| Ricketts City Of STP | Ricketts | 0.0015 |
| Mount Sterling, City Of STP | Mount Sterling | 0.0013 |
| Ainsworth City Of STP | Ainsworth | — |
| Alburnett WWTP | Alburnett | — |
| Allerton City Of STP North | Allerton | — |
| Alvord City Of STP | Alvord | — |
| Andover City Of STP | Andover | — |
| Andrew WWTP | Andrew | — |
| Anthon City Of STP | Anthon | — |
| Arcadia City Of STP | Arcadia | — |
| Arispe City Of STP | Arispe | — |
| Arlington City Of STP | Arlington | — |
| Arthur City Of STP | Arthur | — |
| Ashton City Of STP | Ashton | — |
| Auburn City Of STP | Auburn | — |
| Aurora City Of STP | Aurora | — |
| Avery City Of STP-Rathbun Rwa | Centerville | — |
| Ayrshire, City Of STP | Ayrshire | — |
| Badger City Of STP | Badger | — |
| Baldwin WWTP | Baldwin | — |
| Bancroft City Of STP | Bancroft | — |
| Barnes City, City Of STP | Barnes City | — |
| Barnum City Of STP | Barnum | — |
| Batavia City Of STP | Batavia | — |
| Battle Creek WWTP | Battle Creek | — |
| Beaman WWTP | Beaman | — |
| Bennett City Of STP | Bennett | — |
| Bernard WWTP | Bernard | — |
| Blairsburg City Of STP | Blairsburg | — |
| Blakesburg City Of STP | Blakesburg | — |
| Blockton City Of (southern Ia Rural Water Assn.) | Blockton | — |
| Bode City Of STP | Bode | — |
| Bonaparte City Of STP | Bonaparte | — |
| Boxholm WWTP | Boxholm | — |
| Braddyville City Of STP | Braddyville | — |
| Brayton City Of STP | Brayton | — |
| Breda WWTP | Breda | — |
| Bridgewater City Of STP | Bridgewater | — |
| Brunsville City Of STP | Brunsville | — |
| Burt City Of STP | Burt | — |
| Bussey City Of STP | Bussey | — |
| Calamus City Of STP | Calamus | — |
| Callender City Of STP | Callender | — |
| Calumet City Of STP | Calumet | — |
| Cambridge City Of STP | Cambridge | — |
| Cantril City Of STP | Cantril | — |
| Castalia City Of STP | Castalia | — |
| Center Junction, City Of STP | Center Junction | — |
| Charlotte City Of STP | Charlotte | — |
| Charter Oak City Of STP | Charter Oak | — |
| Cherokee WWTP | Cherokee | — |
| Chester City Of STP | Chester | — |
| Chillicothe,city Of-(wapello Rural Water Assn). | Chillicothe | — |
| Churdan City Of STP | Churdan | — |
| Clare City Of STP | Clare | — |
| Clarion, City Of STP | Clarion | — |
| Cleghorn WWTP | Cleghorn | — |
| Clemons City Of STP | Clemons | — |
| Clutier City Of STP | Clutier | — |
| Coin City Of STP | Coin | — |
| Collins City Of STP | Collins | — |
| Colo City Of STP | Colo | — |
| Conesville City Of STP | Conesville | — |
| Conroy, Iowa - Poweshiek Water Assoc | Marengo | — |
| Crawfordsville WWTP | Crawfordsville | — |
| Crescent WWTP | Crescent | — |
| Cromwell, City-STP -Sirwa | Creston | — |
| Crystal Lake WWTP | Crystal Lake | — |
| Cumberland WWTP | Cumberland | — |
| Cushing City Of STP | Cushing | — |
| Cylinder City Of STP | Cylinder | — |
| Danbury City Of STP | Danbury | — |
| Davenport, City Of-West Locust Lagoon | Davenport | — |
| Dayton City Of STP | Dayton | — |
| Decatur City Sewer Treatment Plant | Decatur | — |
| Dedham City Of STP | Dedham | — |
| Deep River, City Of STP | Deep River | — |
| Defiance City Of STP | Defiance | — |
| Delaware City Of STP | Delaware | — |
| Delhi City Of STP | Delhi | — |
| Delmar, City Of STP | Delmar | — |
| Denmark Sanitary District STP | Denmark | — |
| Derby City Of STP | Derby | — |
| Dewar Sanitary District STP | Dewar | — |
| Dexter City Of STP | Dexter | — |
| Diagonal City Of STP | Diagonal | — |
| Dixon City Of STP | Dixon | — |
| Donahue City Of STP | Donahue | — |
| Doon City Of STP | Doon | — |
| Douds/leando,city Of(rathbun Regional Water Assoc) | Douds | — |
| Dougherty City Of STP | Dougherty | — |
| Dow City, City Of STP | Dow City | — |
| Drakesville, City Of-(rathbun Regional Water Assoc.) | Drakesville | — |
| Duncombe City Of STP | Duncombe | — |
| Dundee City Of STP | Dundee | — |
| Early City Of STP | Early | — |
| East Peru City Of STP (warren Water District) | Peru | — |
| Eddyville, City Of STP | Eddyville | — |
| Elberon City Of STP | Elberon | — |
| Elliott City Of STP | Elliott | — |
| Elwood Community Sanitary District | Elwood | — |
| Emerson City Of STP | Emerson | — |
| Evansdale City Of STP | Evansdale | — |
| Exira City Of STP | Exira | — |
| Exline, City Of, STP | Exline | — |
| Fairview, Community Of | Anamosa | — |
| Farmington City Of STP | Farmington | — |
| Fenton City Of STP | Fenton | — |
| Fertile City Of STP | Fertile | — |
| Fort Atkinson City Of STP | Fort Atkinson | — |
| Fostoria WWTP | Fostoria | — |
| Frederika City Of STP | Frederika | — |
| Fremont City Of STP | Fremont | — |
| Garden Grove City Of STP | Garden Grove | — |
| Garrison WWTP | Garrison | — |
| Garwin City Of STP | Garwin | — |
| Goodell City Of STP | Goodell | — |
| Goose Lake City Of STP | Goose Lake | — |
| Graettinger City Of STP | Graettinger | — |
| Grafton City Of STP | Grafton | — |
| Grand Junction WWTP | Grand Junction | — |
| Grand River WWTP | Grand River | — |
| Granville City Of STP | Granville | — |
| Gravity, City Of-(southern Iowa Rural Water Association) | Gravity | — |
| Greeley City Of STP | Greeley | — |
| Green Mountain - Iowa Regional Utilities Assoc. | Garwin | — |
| Gruver City Of | Gruver | — |
| Halbur City Of (west Central Ia Rural Water Assn) | Halbur | — |
| Hancock City Of STP | Hancock | — |
| Harcourt, City Of STP | Harcourt | — |
| Harper, City Of STP | Harper | — |
| Harris City Of STP | Harris | — |
| Harvey City Of STP | Harvey | — |
| Hawkeye City Of STP | Hawkeye | — |
| Henderson City Of STP | Henderson | — |
| Hillsboro City Of STP | Hillsboro | — |
| Holland WWTP | Holland | — |
| Holy Cross City Of STP | Holy Cross | — |
| Hornick City Of STP | Hornick | — |
| Houghton City Of STP | Houghton | — |
| Hubbard City Of STP | Hubbard | — |
| Ionia WWTP | Ionia | — |
| Ireton City Of STP | Ireton | — |
| Irwin City Of STP | Irwin | — |
| Joice, City Of STP | Joice | — |
| Kamrar City Of STP | Kamrar | — |
| Kellerton City Of STP | Kellerton | — |
| Kellogg WWTP | Kellogg | — |
| Kensett, City Of-STP | Kensett | — |
| Keomah Village City Of STP | Oskaloosa | — |
| Keswick, City Of STP | Keswick | — |
| Kirkville, City Of | Ottumwa | — |
| La Motte City Of STP | La Motte | — |
| Lacona City Of STP | Lacona | — |
| Lake Cornelia Sanitary District | Clarion | — |
| Lamont WWTF | Lamont | — |
| Lanesboro City Of STP | Lanesboro | — |
| Larchwood City Of STP | Larchwood | — |
| Larrabee WWTP | Larrabee | — |
| Latimer-Coulter WWTP | Latimer | — |
| Lawler City Of STP | Lawler | — |
| Lawton City Of STP | Lawton | — |
| Le Mars City Of STP | Le Mars | — |
| Lehigh City Of STP | Lehigh | — |
| Leighton City Of STP | Leighton | — |
| Leland City Of STP | Leland | — |
| Letts City Of STP | Letts | — |
| Lewis WWTP | Lewis | — |
| Liberty Center City Of (warren Co. Board Of Supervisors) | Liberty Center | — |
| Libertyville WWTP | Libertyville | — |
| Lidderdale WWTP | Lidderdale | — |
| Linden City Of STP | Linden | — |
| Lineville City Of STP | Lineville | — |
| Linn Grove WWTP | Linn Grove | — |
| Liscomb City Of STP | Liscomb | — |
| Little Rock City Of STP | Little Rock | — |
| Little Sioux River Sioux STP | Little Sioux | — |
| Livermore WWTP | Livermore | — |
| Lockridge WWTP | Lockridge | — |
| Lone Rock, City Of STP | Lone Rock | — |
| Lorimor City Of STP | Lorimor | — |
| Lost Nation City Of STP | Lost Nation | — |
| Lu Verne, City Of STP | Lu Verne | — |
| Luana City Of STP | Luana | — |
| Lucas City Of STP (rathbun Regional Water Association) | Lucas | — |
| Luxemburg WWTP | Luxemburg | — |
| Lynnville City Of STP | Lynnville | — |
| Macedonia City Of STP | Macedonia | — |
| Macksburg, City Of STP | Macksburg | — |
| Malcom City Of STP | Malcom | — |
| Mallard City Of STP | Mallard | — |
| Manilla WWTP | Manilla | — |
| Marble Rock WWTP | Marble Rock | — |
| Marshalltown City Of STP | Marshalltown | — |
