Diquat violations in Oklahoma
105 active public water systems in Oklahoma had a Diquat violation in the past three years. What Diquat is and why it matters.
Health effects: Chronic exposure to diquat is associated with cataracts and kidney damage in animal studies. Acute high-level exposure causes gastrointestinal distress. EPA has not classified diquat as a human carcinogen. Individuals with kidney conditions may be at elevated risk from chronic exposure.
Systems with a Diquat violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Tinker Air Force Base Oklahoma County |
24,645 | 4 | 1 | |
|
Logan CO Rwd #1 Logan County |
8,907 | 2 | 0 | |
|
Kingfisher Kingfisher County |
5,073 | 3 | 0 | |
|
Nichols Hills Oklahoma County |
4,020 | 5 | 0 | |
|
Grady CO Rwd #6 Grady County |
3,930 | 11 | 0 | |
|
Choctaw UA Oklahoma County |
3,926 | 3 | 1 | |
|
Elgin Pwa Comanche County |
3,300 | 9 | 1 | |
|
Joseph Harp Corr Inst Cleveland County |
3,000 | 4 | 0 | |
|
Commerce Ottawa County |
2,645 | 7 | 1 | |
|
Davis Murray County |
2,610 | 6 | 0 | |
|
Oklahoma City Zoo Oklahoma County |
2,500 | 5 | 0 | |
|
Prague Lincoln County |
2,395 | 7 | 1 | |
|
Pawnee Pawnee County |
2,230 | 9 | 1 | |
|
Okla Christian University Oklahoma County |
1,800 | 2 | 0 | |
|
Oilton Creek County |
1,435 | 14 | 5 | |
|
Medford Grant County |
1,172 | 3 | 0 | |
|
Laverne Harper County |
1,097 | 4 | 0 | |
|
Frontier City Oklahoma County |
1,040 | 6 | 1 | |
|
Woodward CO Rwd #2 Woodward County |
920 | 5 | 0 | |
|
Tipton Tillman County |
916 | 7 | 3 | |
|
Bryan Co. Rwd #9 Bryan County |
820 | 3 | 0 | |
|
Bridge Creek School Grady County |
800 | 3 | 0 | |
|
Welch Pwa Craig County |
800 | 5 | 0 | |
|
Ottawa CO Rwd #5 Ottawa County |
750 | 7 | 0 | |
|
Alex Grady County |
635 | 8 | 2 | |
|
Calumet Pwa Canadian County |
600 | 4 | 0 | |
|
Washington McClain County |
600 | 2 | 0 | |
|
Washington Elementary School Cleveland County |
600 | 1 | 0 | |
|
Arnett Ellis County |
496 | 3 | 0 | |
|
Grady CO Rwd #2 Grady County |
455 | 5 | 0 | |
|
Jennings Pawnee County |
400 | 5 | 1 | |
|
Seneca-Cayuga Nation Delaware County |
400 | 10 | 3 | |
|
Carmen Public Works Authority Alfalfa County |
355 | 11 | 3 | |
|
Blue Quail Estates Canadian County |
350 | 2 | 0 | |
|
Ralston Pawnee County |
335 | 3 | 0 | |
|
Robin Hill School Cleveland County |
330 | 4 | 0 | |
|
Nicoma Park Oklahoma County |
318 | 4 | 0 | |
|
Woodward CO Rwd #1 Woodward County |
315 | 4 | 0 | |
|
Grady CO Rwd #1 Grady County |
300 | 7 | 3 | |
|
Lakewood Village Delaware County |
293 | 7 | 2 | |
|
Wildfire Estates Homeowners Cleveland County |
285 | 8 | 3 | |
|
Jones State Central Middle School Oklahoma County |
280 | 5 | 2 | |
|
Roosevelt Pwa Kiowa County |
280 | 4 | 0 | |
|
Eakly Development Corp Caddo County |
277 | 4 | 0 | |
|
Lakeview Elementary School Cleveland County |
250 | 1 | 0 | |
|
Lookeba Sickles School Caddo County |
250 | 8 | 2 | |
|
Breckinridge Pwa Garfield County |
239 | 6 | 1 | |
|
Spring Cove RV Park&marina Onlake Hudson Mayes County |
225 | 10 | 2 | |
|
Summit Ridge Retirement Center, Inc. Oklahoma County |
200 | 1 | 0 | |
|
Meno Major County |
195 | 3 | 1 |
About this data
A system is counted once if any of its violations in the past three years involved Diquat, including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not Diquat 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.