TTHM (Total Trihalomethanes) violations in Missouri
107 active public water systems in Missouri had a TTHM (Total Trihalomethanes) violation in the past three years, 18 of them in the latest quarter of EPA's data. What TTHM (Total Trihalomethanes) is and why it matters.
Systems with a TTHM (Total Trihalomethanes) violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Woodland R IV Schools Bollinger County |
914 | 2 | 0 | |
|
Lilbourn PWS Lilbourn · New Madrid County |
902 | 8 | 0 | |
|
Oregon County Pwsd 1 Alton · Oregon County |
900 | 2 | 0 | |
|
Braymer PWS Braymer · Caldwell County |
878 | 6 | 1 | |
|
Lagrange PWS La Grange · Lewis County |
875 | 4 | 1 | |
|
Grant City PWS Grant City · Worth County |
850 | 3 | 1 | |
|
Ellington PWS Ellington · Reynolds County |
790 | 4 | 1 | |
|
Bevier PWS Bevier · Macon County |
762 | 2 | 0 | |
|
Perry County Pwsd 2 Perryville · Perry County |
750 | 2 | 0 | |
|
Roaring River State Park Barry County |
750 | 1 | 0 | |
|
S K & M Water and Sewer Company Perry County |
750 | 7 | 0 | |
|
Meadow Ridge Subdivision Taney County |
710 | 5 | 1 | |
|
Morley PWS Morley · Scott County |
699 | 5 | 2 | |
|
Cleveland PWS Cleveland · Cass County |
690 | 4 | 1 | |
|
ST Charles County Pwsd 2 North Oak DR Warren County |
660 | 1 | 0 | |
|
Matthews PWS Matthews · New Madrid County |
628 | 3 | 1 | |
|
Platte County Pwsd 3 Weston · Platte County |
615 | 2 | 0 | |
|
Andrew County Pwsd 4 Andrew County |
600 | 4 | 0 | |
|
Pilot Knob Rural WD 1 Doe Run Area St. Francois County |
507 | 3 | 1 | |
|
Hale PWS Hale · Carroll County |
480 | 3 | 1 | |
|
Farber PWS Farber · Audrain County |
450 | 3 | 1 | |
|
Parma PWS Parma · New Madrid County |
450 | 5 | 1 | |
|
Bull Creek Village Taney County |
400 | 2 | 0 | |
|
Daviess County Pwsd 3 Daviess County |
400 | 1 | 0 | |
|
Chamois PWS Chamois · Osage County |
396 | 5 | 0 | |
|
Starling MHP Jefferson County |
342 | 1 | 0 | |
|
Altenburg PWS Altenburg · Perry County |
341 | 6 | 2 | |
|
Hume PWS Hume · Bates County |
330 | 3 | 0 | |
|
Mercer PWS Mercer · Mercer County |
318 | 1 | 0 | |
|
Cainsville PWS Cainsville · Harrison County |
290 | 3 | 0 | |
|
Liberty Utilities Lakeland Hts Water CO Wappapello · Butler County |
290 | 1 | 0 | |
|
Bates County Pwsd 1 Bates County |
268 | 2 | 0 | |
|
Forest City PWS Forest City · Holt County |
260 | 1 | 0 | |
|
Keithley Beach Subd Warsaw · Benton County |
240 | 4 | 1 | |
|
Mayview PWS Mayview · Lafayette County |
211 | 1 | 0 | |
|
Mendon PWS Mendon · Chariton County |
207 | 2 | 1 | |
|
Curryville PWS Curryville · Pike County |
203 | 3 | 1 | |
|
Killarney Shores Subd Ironton · Iron County |
203 | 7 | 1 | |
|
Hunnewell PWS Hunnewell · Shelby County |
184 | 3 | 1 | |
|
Blackwater PWS Blackwater · Cooper County |
181 | 5 | 0 | |
|
Anniston PWS Anniston · Mississippi County |
175 | 6 | 1 | |
|
High Ridge Manor Subd Jefferson County |
175 | 3 | 1 | |
|
Vanduser PWS Vanduser · Scott County |
168 | 6 | 1 | |
|
Forest Park Deer Park Stone County |
150 | 3 | 0 | |
|
River Cement Company Jefferson County |
145 | 4 | 1 | |
|
Rosendale PWS Rosendale · Andrew County |
142 | 3 | 0 | |
|
Our Lady of the Snow School Eugene · Miller County |
100 | 3 | 2 | |
|
South Greenfield PWS S. Greenfield · Dade County |
100 | 3 | 1 | |
|
Mosby PWS Mosby · Clay County |
93 | 4 | 0 | |
|
Circle C MHP Franklin County |
75 | 3 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved TTHM (Total Trihalomethanes), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not TTHM (Total Trihalomethanes) 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 Missouri 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.