Systems with a yearly average at or above an EPA-based study benchmark
5.1%7 of 136 active community water systems
All 136 systems had enough required samples to calculate a yearly average. 7 had at least one yearly average at or above a study benchmark; 129 did not.
EPA-based study benchmark: the unrounded cutoff this research uses to reproduce EPA’s January 2026 technical-assistance classification around the April 2024 federal levels. It is not a current standard or compliance finding and cannot determine household exposure or health risk.
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Find your water system
ZIP codes are used only to route visitors to public water systems that reported serving them. Confirm the actual provider using a water bill or utility record.
Compound summary
System counts in Oklahoma
Each count shows how many included water systems had a yearly average at or above the named study benchmark.
| Study benchmark | Systems at or above benchmark | Water systems included | Percent |
|---|---|---|---|
| PFOA: 4.05 ppt study benchmark (reproduces EPA classification around 4 ppt) | 0 | 136 | 0.0% |
| PFOS: 4.05 ppt study benchmark (reproduces EPA classification around 4 ppt) | 7 | 136 | 5.1% |
| PFHxS: 15 ppt study benchmark (reproduces EPA classification around 10 ppt) | 1 | 136 | 0.7% |
| PFNA: 15 ppt study benchmark (reproduces EPA classification around 10 ppt) | 0 | 136 | 0.0% |
| HFPO-DA: 15 ppt study benchmark (reproduces EPA classification around 10 ppt) | 0 | 136 | 0.0% |
| Hazard Index: 1.5 study benchmark with at least two detected components (reproduces EPA classification around 1) | 0 | 136 | 0.0% |
System directory
Community water systems with complete monitoring
“Complete monitoring” means at least one sampling location had all required samples needed for a yearly average. Each PWSID appears once, preventing double counting across ZIP associations.
| Public water system | PWSID | Population served | Primary source | Sampling locations | Study benchmark result |
|---|---|---|---|---|---|
| ALFALFA CO RWS & SWMD #1 NORTH | OK2000201 | 600 | Ground water | 2 | Below all study benchmarks |
| ALTUS | OK1011501 | 18,717 | Surface water | 1 | Below all study benchmarks |
| ALTUS AFB | OK3003303 | 4,617 | Surface water purchased | 1 | Below all study benchmarks |
| ALVA | OK2007603 | 5,208 | Ground water | 1 | Below all study benchmarks |
| ANADARKO PUBLIC WORKS AUTHORITY | OK1010806 | 6,804 | Surface water | 1 | Below all study benchmarks |
| ARDMORE | OK1010814 | 24,893 | Surface water | 1 | Below all study benchmarks |
| BARTLESVILLE | OK1021401 | 34,748 | Surface water | 1 | Below all study benchmarks |
| BETHANY | OK2005519 | 20,307 | Groundwater under influence of surface water | 1 | Below all study benchmarks |
| BIXBY PUBLIC WORKS AUTHORITY | OK3007243 | 18,750 | Surface water purchased | 1 | Below all study benchmarks |
| BLACKWELL MUNICIPAL AUTHORITY | OK1021101 | 7,668 | Surface water | 1 | Below all study benchmarks |
| BRISTOW MUNICIPAL AUTHORITY | OK2001910 | 3,700 | Ground water | 5 | Below all study benchmarks |
| BROKEN ARROW MUNICIPAL AUTHORITY | OK1021508 | 116,330 | Surface water | 1 | At or above a study benchmark |
| BROKEN BOW PWA | OK1010214 | 4,320 | Surface water | 1 | Below all study benchmarks |
| BRYAN CO. RW&SD #5 | OK3000704 | 8,325 | Surface water purchased | 2 | Below all study benchmarks |
| BRYAN CO. RWS & SWMD #2 | OK1010604 | 6,270 | Surface water | 2 | Below all study benchmarks |
| CADDO CO RWD #3 | OK2000816 | 3,900 | Ground water | 10 | Below all study benchmarks |
| CAMARGO RWD #2 | OK2002202 | 150 | Ground water | 1 | Below all study benchmarks |
| CHICKASAW WINSTAR | 062004336 | 8,376 | Ground water | 4 | Below all study benchmarks |
| CHICKASHA MUNICIPAL AUTHORITY | OK1010821 | 16,036 | Surface water | 1 | Below all study benchmarks |
| CHOCTAW | OK2005510 | 3,926 | Ground water | 5 | Below all study benchmarks |
| CLAREMORE | OK1021512 | 15,873 | Surface water | 1 | Below all study benchmarks |
| CLINTON | OK1010828 | 8,883 | Surface water | 2 | Below all study benchmarks |
| COLLINSVILLE | OK1021505 | 5,400 | Surface water | 1 | Below all study benchmarks |
| COWETA | OK1021509 | 9,450 | Surface water | 1 | Below all study benchmarks |
| CRAIG CO RWD #2 | OK3001802 | 4,250 | Surface water purchased | 2 | Below all study benchmarks |
| CREEK CO RWD # 1 | OK1020419 | 5,675 | Surface water | 1 | Below all study benchmarks |
| CREEK CO RWD # 2 | OK3001902 | 12,788 | Surface water purchased | 3 | Below all study benchmarks |
| CUSHING | OK2006061 | 8,371 | Ground water | 1 | Below all study benchmarks |
| DEL CITY | OK1020805 | 22,128 | Surface water | 9 | Below all study benchmarks |
| DEWEY PUBLIC WORKS AUTHORITY | OK3007402 | 3,490 | Surface water purchased | 2 | Below all study benchmarks |
| DUNCAN PUBLIC UTILITIES AUTHORITY | OK1010809 | 23,000 | Surface water | 2 | Below all study benchmarks |
| DURANT UTILITIES AUTHORITY | OK1010601 | 15,545 | Surface water | 1 | Below all study benchmarks |
| EASTERN SHAWNEE | 061000101 | 796 | Ground water | 1 | Below all study benchmarks |
| EDMOND PWA - ARCADIA | OK1020723 | 79,408 | Surface water | 18 | Below all study benchmarks |
| EL RENO | OK2000902 | 16,212 | Surface water purchased | 1 | Below all study benchmarks |
| ELK CITY | OK2000501 | 10,510 | Ground water | 1 | Below all study benchmarks |
| ENID | OK2002412 | 49,347 | Surface water | 5 | Below all study benchmarks |
| EUFAULA PWA | OK1020514 | 2,766 | Surface water | 1 | Below all study benchmarks |
| FORT SILL HQUSAFACFS | OK3001601 | 23,000 | Surface water purchased | 1 | Below all study benchmarks |
| GARVIN CO RWD #4 | OK3002503 | 1,340 | Surface water purchased | 2 | Below all study benchmarks |
| GLENPOOL WATER | OK3007223 | 12,500 | Surface water purchased | 1 | Below all study benchmarks |
| GRADY CO RWD #6 | OK3002603 | 3,930 | Ground water | 1 | Below all study benchmarks |
| GROVE MUNICIPAL SERVICES AUTH. | OK1021614 | 7,311 | Surface water | 1 | Below all study benchmarks |
| GUYMON | OK2007003 | 11,442 | Ground water | 6 | Below all study benchmarks |
| HALLETT PUBLIC WORKS AUTHORITY | OK2005905 | 168 | Ground water | 1 | Below all study benchmarks |
| HARRAH | OK2005506 | 4,190 | Ground water | 6 | Below all study benchmarks |
| HEAVENER UTILITY AUTH - PSG | OK1020101 | 3,000 | Surface water purchased | 2 | Below all study benchmarks |
| HENRYETTA | OK1020709 | 6,096 | Surface water | 1 | Below all study benchmarks |
| HOBART | OK1011502 | 3,746 | Surface water purchased | 1 | Below all study benchmarks |
| HUGO MUNICIPAL AUTHORITY | OK1010314 | 5,536 | Surface water | 1 | Below all study benchmarks |
| HYDRO PWA | OK2000812 | 1,060 | Ground water | 1 | Below all study benchmarks |
| IDABEL PWA | OK1010203 | 6,952 | Surface water | 1 | Below all study benchmarks |
| JEFFERSON CO CONS RWD #1 | OK3003401 | 8,398 | Surface water purchased | 2 | Below all study benchmarks |
| JENKS PWA | OK3007201 | 16,924 | Surface water purchased | 1 | Below all study benchmarks |
| KETCHUM PWA | OK1021612 | 4,025 | Surface water | 1 | Below all study benchmarks |
| LAWTON | OK1011303 | 92,757 | Surface water | 2 | Below all study benchmarks |
| LEFLORE CO. RWD #2 | OK3004007 | 4,700 | Surface water purchased | 1 | Below all study benchmarks |
| LOGAN CO RWD #1 | OK2004207 | 8,907 | Surface water purchased | 11 | Below all study benchmarks |
| LONE GROVE | OK2001007 | 4,863 | Ground water | 5 | Below all study benchmarks |
| MANNFORD | OK1020909 | 3,935 | Surface water | 1 | Below all study benchmarks |
| MARLOW PWA | OK2006907 | 4,600 | Ground water | 2 | Below all study benchmarks |
| MARSHALL COUNTY WATER CORP | OK1010848 | 17,587 | Surface water | 1 | Below all study benchmarks |
| MAYES CO RWD # 2 | OK3004608 | 6,280 | Surface water purchased | 1 | At or above a study benchmark |
| MAYES CO RWD # 5 | OK3004616 | 3,360 | Surface water purchased | 2 | Below all study benchmarks |
| MAYES CO RWD # 6 | OK1021666 | 3,750 | Surface water | 1 | Below all study benchmarks |
| MCALESTER PWA | OK1020609 | 18,206 | Surface water | 1 | Below all study benchmarks |
| MCCURTAIN CO. RWD #1 | OK3004806 | 3,842 | Surface water purchased | 1 | Below all study benchmarks |
| MCCURTAIN CO. RWD #7 | OK3004801 | 1,847 | Surface water purchased | 2 | Below all study benchmarks |
| MCCURTAIN CO. RWD #9 | OK3004820 | 999 | Surface water purchased | 1 | Below all study benchmarks |
| MCINTOSH CO. RWD #8 (TEXANNA) | OK1020529 | 3,574 | Surface water | 1 | Below all study benchmarks |
| MIAMI | OK2005813 | 13,704 | Ground water | 4 | Below all study benchmarks |
| MIDWEST CITY | OK1020806 | 55,935 | Surface water | 12 | Below all study benchmarks |
| MOORE | OK2001412 | 55,083 | Surface water purchased | 24 | Below all study benchmarks |
| MURRAY CO RWD # 1 | OK2005012 | 4,800 | Ground water | 1 | Below all study benchmarks |
| MUSKOGEE | OK1021607 | 38,310 | Surface water | 1 | Below all study benchmarks |
| MUSKOGEE CO. RWD #1 (OKTAHA) | OK3005106 | 2,280 | Surface water purchased | 1 | Below all study benchmarks |
| MUSKOGEE CO. RWD #5 | OK3005107 | 4,135 | Surface water purchased | 2 | Below all study benchmarks |
| MUSTANG | OK2000922 | 18,576 | Surface water purchased | 2 | Below all study benchmarks |
| NEWCASTLE | OK2004704 | 7,900 | Surface water purchased | 2 | Below all study benchmarks |
| NICHOLS HILLS | OK2005501 | 4,020 | Ground water | 2 | Below all study benchmarks |
| NOBLE | OK2001411 | 5,750 | Ground water | 5 | Below all study benchmarks |
| NORMAN | OK1020801 | 104,868 | Surface water | 14 | Below all study benchmarks |
| NOWATA MUNICIPAL AUTHORITY | OK1021503 | 3,971 | Surface water | 1 | Below all study benchmarks |
| OKFUSKEE CO. RWD #3 | OK3005401 | 1,823 | Surface water purchased | 1 | Below all study benchmarks |
| OKLA CHRISTIAN UNIVERSITY | OK7005566 | 1,800 | Ground water | 1 | Below all study benchmarks |
| OKLA ORDNANCE WORKS AUTHORITY | OK1021602 | 4,000 | Surface water | 1 | Below all study benchmarks |
| OKLAHOMA CITY | OK1020902 | 644,000 | Surface water | 2 | Below all study benchmarks |
| OKLAHOMA UNIVERSITY | OK3001414 | 34,000 | Surface water purchased | 1 | Below all study benchmarks |
| OKMULGEE | OK1020708 | 13,495 | Surface water | 1 | Below all study benchmarks |
| OSU WATER PLANT | OK1020910 | 13,000 | Surface water | 1 | Below all study benchmarks |
| OTTAWA CO RWD # 4 | OK2005801 | 652 | Ground water | 5 | Below all study benchmarks |
| OWASSO | OK3007218 | 23,000 | Surface water purchased | 1 | Below all study benchmarks |
| PAULS VALLEY | OK1010808 | 6,256 | Surface water | 1 | Below all study benchmarks |
| PAWHUSKA | OK1021301 | 3,800 | Surface water | 1 | Below all study benchmarks |
| PERRY WATER & LIGHT DEPT | OK1021206 | 5,230 | Surface water | 1 | Below all study benchmarks |
| PIEDMONT MUNICPAL AUTHORITY | OK2000909 | 7,542 | Surface water purchased | 3 | Below all study benchmarks |
| PITTSBURG CO. RWD #11 (KIOWA) | OK3006105 | 790 | Surface water purchased | 1 | Below all study benchmarks |
| PITTSBURG CO. RWD #16 | OK3006106 | 1,268 | Surface water purchased | 1 | Below all study benchmarks |
| PONCA CITY MUN WATER | OK1021202 | 27,155 | Surface water | 1 | At or above a study benchmark |
| PONTOTOC CO RWD # 7 | OK3006215 | 4,863 | Ground water purchased | 1 | Below all study benchmarks |
| PONTOTOC CO RWD # 8 | OK2006215 | 4,250 | Ground water | 1 | Below all study benchmarks |
| PORUM PWA | OK1020302 | 5,000 | Surface water | 1 | Below all study benchmarks |
| POTTAWATOMIE CO. RWD #3 (DALE PLANT) | 061020808 | 5,780 | Ground water | 1 | Below all study benchmarks |
| PURCELL | OK2004701 | 6,693 | Ground water | 1 | Below all study benchmarks |
| PUSHMATAHA CO. RWD #3 | OK1010318 | 4,825 | Surface water | 1 | Below all study benchmarks |
| ROGERS CO RWD # 3 COT STA | OK3006650 | 10,750 | Surface water purchased | 1 | Below all study benchmarks |
| ROGERS CO RWD # 3 LAKE PLANT | OK1021513 | 10,470 | Surface water | 1 | Below all study benchmarks |
| ROGERS CO RWD # 4 | OK1021506 | 7,725 | Surface water | 1 | Below all study benchmarks |
| ROGERS CO RWD # 5 | OK1021507 | 11,782 | Surface water | 1 | Below all study benchmarks |
| ROGERS CO RWD # 8 | OK3006606 | 3,375 | Surface water purchased | 1 | Below all study benchmarks |
| SAND SPRINGS | OK1020420 | 28,774 | Surface water | 1 | Below all study benchmarks |
| SAPULPA | OK1020404 | 19,702 | Surface water | 1 | Below all study benchmarks |
| SAYRE | OK2000508 | 4,375 | Ground water | 1 | Below all study benchmarks |
| SEMINOLE | OK2006720 | 6,899 | Ground water | 17 | Below all study benchmarks |
| SEQUOYAH CO. WATER ASSOCIATION | OK1020210 | 13,460 | Surface water | 1 | Below all study benchmarks |
| SHAWNEE MUNICIPAL AUTHORITY | OK1020504 | 29,990 | Surface water | 1 | Below all study benchmarks |
| SKIATOOK PWA | OK1021313 | 8,110 | Surface water | 1 | Below all study benchmarks |
| SOUTHERN OKLA WATER CORP | OK1010830 | 11,250 | Surface water | 11 | Below all study benchmarks |
| STEPHENS CO RWD #5 | OK2006969 | 6,426 | Surface water purchased | 4 | Below all study benchmarks |
| STILLWATER WATER PLANT | OK1021220 | 53,000 | Surface water | 1 | At or above a study benchmark |
| SULPHUR | OK2005001 | 4,929 | Ground water | 1 | Below all study benchmarks |
| TAHLEQUAH PWA | OK1021701 | 14,458 | Surface water | 2 | Below all study benchmarks |
| TECUMSEH UTILITY AUTHORITY | OK1020506 | 6,098 | Surface water | 1 | Below all study benchmarks |
| TINKER AFB BIO-ENV ENG | OK2005508 | 24,645 | Ground water | 14 | Below all study benchmarks |
| TRI-COUNTY RWD #2 | OK2006362 | 5,172 | Ground water | 3 | At or above a study benchmark |
| TULSA | OK1020418 | 413,000 | Surface water | 2 | Below all study benchmarks |
| TUTTLE | OK2002608 | 4,500 | Ground water | 3 | Below all study benchmarks |
| WAGONER CO. RWD #4 | OK1021529 | 25,792 | Surface water | 1 | At or above a study benchmark |
| WAGONER CO. RWD #5 | OK1021528 | 4,251 | Surface water | 1 | At or above a study benchmark |
| WAGONER CO. RWD #9 | OK1021527 | 4,363 | Surface water | 1 | Below all study benchmarks |
| WASHINGTON CO RWD #3 (NEW,#1) | OK1021418 | 25,375 | Surface water | 1 | Below all study benchmarks |
| WATONGA | OK2000602 | 2,816 | Ground water | 2 | Below all study benchmarks |
| WEATHERFORD | OK2002002 | 10,833 | Ground water | 2 | Below all study benchmarks |
| WEWOKA PUBLIC WORKS AUTHORITY | OK1020510 | 3,450 | Surface water | 1 | Below all study benchmarks |
| WOODWARD | OK2007701 | 15,000 | Ground water | 3 | Below all study benchmarks |
| YUKON | OK2000910 | 22,498 | Surface water purchased | 1 | Below all study benchmarks |
How the count works
What is included
Each active community water system with enough required samples for a yearly average is counted once, even if it is linked with several ZIP codes. This does not mean every home was tested. Private wells are excluded, and UCMR 5 did not comprehensively monitor every small system. This page does not apply Oklahoma's state-specific standards or determine compliance. Use the official state or territory drinking-water program for current regulatory information.