Overview
EWG's drinking water quality report for Oklahoma shows results of tests conducted by the water utilities in Oklahoma and provided to EWG by the Oklahoma Department of Environmental Quality.
Large utilities in Oklahoma
Below are utilities in Oklahoma serving over 10,000 people, listed alphabetically.
| Utility | Location | People Served |
|---|
| Ada | Ada, OK | 22,600 |
| Altus | Altus, OK | 18,717 |
| Ardmore | Ardmore, OK | 24,893 |
| Bartlesville | Bartlesville, OK | 34,748 |
| Bethany | Bethany, OK | 20,307 |
| Bixby Public Works Authority | Bixby, OK | 18,750 |
| Broken Arrow Municipal Authority | Broken Arrow, OK | 116,330 |
| Chickasha Municipal Authority | Chickasha, OK | 16,036 |
| City of Edmond - Arcadia Lake | Edmond, OK | 79,408 |
| Claremore | Claremore, OK | 15,873 |
| Creek County RWD # 2 | Jenks, OK | 12,788 |
| Del City | Del City, OK | 22,128 |
| Duncan Public Utilities Authority | Duncan, OK | 23,000 |
| Durant | Durant, OK | 15,545 |
| El Reno | El Reno, OK | 16,212 |
| Elk City | Elk City, OK | 10,510 |
| Enid | Enid, OK | 49,347 |
| Fort Sill HQUSAFACFS | Fort Sill, OK | 23,000 |
| Glenpool Water | Glenpool, OK | 12,500 |
| Guymon | Guymon, OK | 11,442 |
| Jenks PWA | Jenks, OK | 16,924 |
| Lawton | Lawton, OK | 92,757 |
| Marshall County Water Corp | Madill, OK | 17,587 |
| McAlester PWA | Mcalester, OK | 18,206 |
| Miami | Miami, OK | 13,704 |
| Midwest City | Midwest City, OK | 55,935 |
| Moore | Moore, OK | 55,083 |
| Muskogee | Muskogee, OK | 38,310 |
| Mustang | Mustang, OK | 18,576 |
| Norman | Norman, OK | 100,939 |
| Oklahoma City | Oklahoma City, OK | 644,000 |
| Okmulgee | Okmulgee, OK | 13,495 |
| OSU Water Plant | Stillwater, OK | 13,000 |
| Owasso | Owasso, OK | 23,000 |
| Ponca City Mun Water | Ponca City, OK | 27,155 |
| Pvia | Wister, OK | 40,000 |
| Rogers County Rural Water District # 3 Lake Plant | Claremore, OK | 10,470 |
| Rogers County RWD # 3 Cot Sta | Claremore, OK | 10,750 |
| Rogers County RWD # 5 | Claremore, OK | 11,782 |
| Sand Springs | Sand Springs, OK | 28,774 |
| Sapulpa | Sapulpa, OK | 19,702 |
| Sequoyah County Water Association | Sallisaw, OK | 13,460 |
| Shawnee Municipal Authority | Shawnee, OK | 29,990 |
| Southern Okla Water Corp | Ardmore, OK | 11,250 |
| Stillwater Water Plant | Stillwater, OK | 53,000 |
| Tahlequah PWA | Tahlequah, OK | 14,458 |
| Tulsa | Tulsa, OK | 471,000 |
| Wagoner County Rwd #4 | Broken Arrow, OK | 25,792 |
| Washington County RWD #3 (new,#1) | Collinsville, OK | 25,375 |
| Weatherford | Weatherford, OK | 10,833 |
| Woodward | Woodward, OK | 15,000 |
| Yukon | Yukon, OK | 22,498 |
Utilities that accumulated/accrued the most violation points as of July 2021 to June 2024 in Oklahoma
The Environmental Protection Agency's Enforcement and Compliance History Online (ECHO) database collects compliance and enforcement-related information for drinking water utilities nationwide. ECHO water quality violation scores take into account federal health-based water quality standards, as well as monitoring, reporting and other drinking water quality requirements. Points are accrued based on specific problems at the utility - violations of health-based drinking water standards receive more points than monitoring and reporting violations - and the length of time until the violations were corrected.
| Utility | Location | People Served | Violation Points |
|---|
Large utilities that accumulated/accrued the most violation points as of July 2021 to June 2024 in Oklahoma
The Environmental Protection Agency's Enforcement and Compliance History Online (ECHO) database collects compliance and enforcement-related information for drinking water utilities nationwide. ECHO water quality violation scores take into account federal health-based water quality standards, as well as monitoring, reporting and other drinking water quality requirements. Points are accrued based on specific problems at the utility - violations of health-based drinking water standards receive more points than monitoring and reporting violations - and the length of time until the violations were corrected.
| Utility | Location | People Served | Violation Points |
|---|
| Southern Okla Water Corp | Ardmore, OK | 11,250 | 105 |
| Okmulgee | Okmulgee, OK | 13,495 | 70 |
| McAlester PWA | Mcalester, OK | 18,206 | 55 |
| Wagoner County Rwd #4 | Broken Arrow, OK | 25,792 | 45 |
| Chickasha Municipal Authority | Chickasha, OK | 16,036 | 40 |
| Rogers County Rural Water District # 3 Lake Plant | Claremore, OK | 10,470 | 31 |
| Marshall County Water Corp | Madill, OK | 17,587 | 30 |
| Duncan Public Utilities Authority | Duncan, OK | 23,000 | 30 |
| Pvia | Wister, OK | 40,000 | 14 |
| Durant | Durant, OK | 15,545 | 10 |
| Altus | Altus, OK | 18,717 | 10 |
| Ardmore | Ardmore, OK | 24,893 | 10 |
| Muskogee | Muskogee, OK | 38,310 | 5 |
| Weatherford | Weatherford, OK | 10,833 | 3 |
| Woodward | Woodward, OK | 15,000 | 3 |
| Enid | Enid, OK | 49,347 | 2 |
| Midwest City | Midwest City, OK | 55,935 | 2 |
| Creek County RWD # 2 | Jenks, OK | 12,788 | 2 |
| Tulsa | Tulsa, OK | 471,000 | 1 |
| Mustang | Mustang, OK | 18,576 | 1 |
| Moore | Moore, OK | 55,083 | 1 |
| Bethany | Bethany, OK | 20,307 | 1 |
| Rogers County RWD # 3 Cot Sta | Claremore, OK | 10,750 | 1 |
Contaminants found in Oklahoma above health guidelines
| Found above health guidelines | Found | |||
|---|---|---|---|---|
| Contaminant | # of Utilities | People Served | # of Utilities | People Served |
| Total trihalomethanes (TTHMs) | 758 | 3,596,874 | 758 | 3,596,874 | ||
| Dibromochloromethane | 713 | 3,548,263 | 726 | 3,556,034 | ||
| Bromodichloromethane | 690 | 3,536,469 | 691 | 3,536,564 | ||
| Haloacetic acids (HAA5) | 652 | 3,443,735 | 652 | 3,443,735 | ||
| Chloroform | 576 | 3,366,032 | 627 | 3,458,819 | ||
| Dichloroacetic acid | 549 | 3,299,131 | 566 | 3,338,629 | ||
| Dibromoacetic acid | 490 | 3,049,924 | 516 | 3,141,219 | ||
| Trichloroacetic acid | 478 | 2,939,736 | 491 | 3,066,739 | ||
| Haloacetic acids (HAA9) | 169 | 2,666,507 | 169 | 2,666,507 | ||
| Radium, combined (-226 & -228) | 479 | 2,409,507 | 499 | 2,461,039 | ||
| Chromium (hexavalent) | 97 | 1,698,086 | 157 | 2,599,339 | ||
| Nitrate & nitrite | 462 | 1,645,363 | 677 | 3,275,361 | ||
| Bromate | 27 | 1,115,689 | 27 | 1,115,689 | ||
| Bromoform | 367 | 1,114,211 | 567 | 3,065,489 | ||
| Chlorite | 75 | 796,086 | 111 | 1,057,592 | ||
| Atrazine | 39 | 754,792 | 46 | 779,950 | ||
| Uranium, combined (pCi/L) | 207 | 715,334 | 274 | 920,290 | ||
| Arsenic | 94 | 483,923 | 94 | 483,923 | ||
| Perfluorohexane sulfonate (PFHXS) | 38 | 389,965 | 38 | 389,965 | ||
| Nitrate | 64 | 319,955 | 87 | 1,211,689 | ||
| Perfluorooctane sulfonate (PFOS) | 30 | 292,898 | 32 | 372,606 | ||
| Bromochloroacetic acid | 139 | 282,523 | 139 | 282,523 | ||
| Chlorate | 18 | 182,075 | 112 | 1,584,689 | ||
| Tetrachloroethylene (perchloroethylene) | 6 | 29,496 | 6 | 29,496 | ||
| Vanadium | 1 | 22,498 | 152 | 2,597,658 | ||
| Perfluorooctanoic acid (PFOA) | 1 | 20,307 | 1 | 20,307 | ||
| Cadmium | 2 | 4,072 | 2 | 4,072 | ||
| Carbon tetrachloride | 3 | 2,951 | 3 | 2,951 | ||
| Trichloroethylene | 1 | 2,086 | 1 | 2,086 | ||
| Thallium | 1 | 200 | 1 | 200 | ||
| Benzene | 1 | 200 | 1 | 200 |
Contaminants found in Oklahoma above legal limits
| Contaminant | # of Utilities | People Served |
|---|
Total trihalomethanes (TTHMs) | 79 | 103,093 | |
Haloacetic acids (HAA5) | 17 | 26,177 | |
Nitrate and nitrite | 15 | 9,112 | |
Nitrate | 2 | 2,940 | |
Radium, combined (-226 and -228) | 1 | 800 | |
Arsenic | 3 | 722 | |
Uranium | 1 | 22 |
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