TTHM (Total Trihalomethanes) violations in Oklahoma
349 active public water systems in Oklahoma had a TTHM (Total Trihalomethanes) violation in the past three years, 123 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 |
|---|---|---|---|---|
|
Roger Mills Rws & Swmd #1 Roger Mills County |
200 | 10 | 2 | |
|
Harper CO Rwd #1 Harper County |
198 | 10 | 1 | |
|
Roger Mills Rws & Swmd #3 (reydon) Roger Mills County |
177 | 5 | 1 | |
|
Rogers CO Rwd #12 Rogers County |
176 | 5 | 0 | |
|
Sharon Utilities Woodward County |
175 | 10 | 2 | |
|
Kenefic Bryan County |
165 | 5 | 0 | |
|
North Vinita Water Coop INC Craig County |
162 | 2 | 0 | |
|
Hickory Meadows Delaware County |
157 | 8 | 5 | |
|
Coal CO Rw&swmg #6 Coal County |
150 | 2 | 0 | |
|
Devol Cotton County |
150 | 3 | 0 | |
|
Garvin McCurtain County |
150 | 5 | 1 | |
|
Dacoma Pwa Woods County |
148 | 6 | 1 | |
|
Fairmont Garfield County |
147 | 5 | 0 | |
|
Ottawa CO Rwd # 3 Ottawa County |
140 | 10 | 4 | |
|
Golden Oaks Home Owners Assn Carter County |
135 | 8 | 4 | |
|
Greenfield Pwa Blaine County |
123 | 5 | 1 | |
|
Hillsdale Pwa Garfield County |
110 | 4 | 0 | |
|
Felt School Cimarron County |
100 | 5 | 0 | |
|
Pine Country Living MHP Pottawatomie County |
100 | 8 | 0 | |
|
Ozark Rural Water INC Cherokee County |
99 | 4 | 2 | |
|
4t Investors LLC Beaver County |
98 | 5 | 1 | |
|
Country East MHP Custer County |
97 | 5 | 1 | |
|
Sooner Utilities-Crutcho Oklahoma County |
93 | 6 | 2 | |
|
Brooksville Pottawatomie County |
90 | 10 | 4 | |
|
Pettit Mountain Water Cherokee County |
90 | 7 | 1 | |
|
Surrey Hills Texas County |
87 | 14 | 4 | |
|
Turkey Ford Public School Dist C010 Ottawa County |
85 | 2 | 0 | |
|
Headrick Jackson County |
84 | 2 | 0 | |
|
Loyal Kingfisher County |
81 | 5 | 0 | |
|
Grady CO Rwd #3 Grady County |
80 | 10 | 4 | |
|
Chisholm Creek Housing Addition Garfield County |
75 | 4 | 0 | |
|
Nowata CO Rwd #5 Nowata County |
70 | 1 | 0 | |
|
Sugar Mountain Retreat Cherokee County |
65 | 4 | 0 | |
|
Oak Ridge Estates I & II Water Assoc. Delaware County |
62 | 11 | 4 | |
|
Hollister Tillman County |
60 | 3 | 1 | |
|
Okla Natl Stockyards Oklahoma County |
60 | 6 | 1 | |
|
Straight School Texas County |
56 | 5 | 0 | |
|
Colbert Boat Club Bryan County |
54 | 4 | 0 | |
|
Hwy 7 East Water Assn Comanche County |
50 | 4 | 1 | |
|
Winter Creek Water Company, LLC Grady County |
46 | 7 | 4 | |
|
Western Farmers Plant Woodward County |
45 | 2 | 0 | |
|
Highway 69 Water Dist. (greer's Sausage) Mayes County |
43 | 7 | 3 | |
|
Walnut Park Estates Osage County |
42 | 11 | 4 | |
|
Woods CO Rwd #2 Woods County |
42 | 4 | 0 | |
|
North Latta Park, LLC Oklahoma County |
39 | 7 | 0 | |
|
Douglas Garfield County |
32 | 4 | 0 | |
|
Gordon's Hollow HOA Canadian County |
25 | 5 | 0 | |
|
Valley View Water Association Comanche County |
25 | 4 | 0 | |
|
Skyview Mobile Home Park Grady County |
24 | 12 | 5 |
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 Oklahoma 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.