Systems reaching a study comparison level
9.7%29 of 300 active community water systems with complete monitoring
All 300 systems had complete monitoring. 29 reached at least one study comparison level; 271 did not. “Study comparison level” means the dated EPA technical cutoff used in this January 2026 research release. It does not determine household exposure, health risk, or current legal compliance.
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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 Ohio
Each count shows how many included water systems reached the named study level.
| Study comparison | Systems reaching level | Water systems included | Percent |
|---|---|---|---|
| PFOA: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 13 | 300 | 4.3% |
| PFOS: study level 4.05 ppt (April 2024 EPA level: 4 ppt) | 19 | 300 | 6.3% |
| PFHxS: study level 15 ppt (April 2024 EPA level: 10 ppt) | 1 | 300 | 0.3% |
| PFNA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 300 | 0.0% |
| HFPO-DA: study level 15 ppt (April 2024 EPA level: 10 ppt) | 0 | 300 | 0.0% |
| Hazard Index: study level 1.5 with at least two detected components (April 2024 EPA level: 1) | 1 | 300 | 0.3% |
System directory
Community water systems with complete monitoring
Each PWSID appears once, preventing double counting across ZIP associations.
| Public water system | PWSID | Population served | Primary source | Sampling locations | Study comparison |
|---|---|---|---|---|---|
| ADA VILLAGE | OH3300012 | 5,334 | Ground water | 1 | Below the study levels |
| ADAMS COUNTY REGIONAL WD PWS | OH0100012 | 21,810 | Ground water | 1 | Below the study levels |
| AKRON CITY PWS | OH7700011 | 280,000 | Surface water | 1 | Below the study levels |
| ALLIANCE CITY PWS | OH7600011 | 22,232 | Surface water | 1 | Below the study levels |
| AMHERST CITY PWS | OH4700003 | 11,797 | Surface water purchased | 2 | Below the study levels |
| ANDOVER-CAMPLANDS WATER | OH0400212 | 6,009 | Ground water | 1 | Below the study levels |
| AQUA OHIO - ASHTABULA | OH0400711 | 32,342 | Surface water | 1 | Below the study levels |
| AQUA OHIO - AURORA E | OH6700512 | 766 | Ground water purchased | 1 | Below the study levels |
| AQUA OHIO - BLACKLICK | OH2502412 | 7,100 | Ground water | 1 | Below the study levels |
| AQUA OHIO - HUBER RIDGE PWS | OH2502512 | 5,393 | Ground water | 1 | Below the study levels |
| AQUA OHIO - LAKE DARBY | OH2502612 | 3,562 | Ground water | 1 | Below the study levels |
| AQUA OHIO - LAWRENCE COUNTY | OH4400803 | 8,130 | Surface water purchased | 1 | Below the study levels |
| AQUA OHIO - MARION | OH5100414 | 47,102 | Surface water | 1 | Below the study levels |
| AQUA OHIO - MASSILLON PWS | OH7604512 | 95,636 | Ground water | 1 | Below the study levels |
| AQUA OHIO - MASURY | OH7802711 | 4,019 | Surface water purchased | 1 | Below the study levels |
| AQUA OHIO - MENTOR | OH4301511 | 74,500 | Surface water | 1 | Below the study levels |
| AQUA OHIO - STRUTHERS | OH5001611 | 58,551 | Surface water | 1 | Below the study levels |
| AQUA OHIO - TIFFIN | OH7400614 | 20,279 | Surface water | 1 | Below the study levels |
| AQUA OHIO - VILLAGE OF JEFFERSON | OH0401812 | 3,226 | Surface water purchased | 1 | Below the study levels |
| ARCHBOLD VILLAGE | OH2600011 | 5,586 | Surface water | 1 | Below the study levels |
| ASHLAND CITY | OH0300112 | 20,648 | Ground water | 1 | Below the study levels |
| ASHVILLE VILLAGE PWS | OH6500012 | 4,529 | Ground water | 1 | Below the study levels |
| ATHENS PWS | OH0500212 | 32,725 | Ground water | 1 | Below the study levels |
| AURORA CITY - CLEVELAND PWS | OH6789112 | 15,852 | Surface water purchased | 1 | Below the study levels |
| AVON CITY PWS | OH4700203 | 23,800 | Surface water purchased | 3 | Below the study levels |
| AVON LAKE CITY PWS | OH4700311 | 23,659 | Surface water | 1 | Below the study levels |
| BARBERTON CITY | OH7700411 | 31,298 | Surface water | 1 | Below the study levels |
| BARNESVILLE, OH | OH0700011 | 6,500 | Surface water | 1 | Reached a study level |
| BEDFORD CITY PWS | OH1800003 | 13,149 | Surface water purchased | 1 | Below the study levels |
| BELLAIRE PUBLIC WATER SYSTEM | OH0700114 | 4,278 | Surface water | 1 | Below the study levels |
| BELLEFONTAINE CITY PWS | OH4600112 | 13,249 | Ground water | 1 | Below the study levels |
| BELLEVUE CITY | OH3900011 | 8,236 | Surface water | 1 | Below the study levels |
| BELMONT CO. SANITARY DISTRICT 3 PWS | OH0700412 | 26,822 | Ground water | 1 | Below the study levels |
| BELPRE CITY PWS | OH8400012 | 6,441 | Ground water | 1 | Below the study levels |
| BEREA CITY PWS | OH1800111 | 18,789 | Surface water | 1 | Below the study levels |
| BETHEL VILLAGE PWS | OH1300116 | 2,620 | Ground water purchased | 1 | Reached a study level |
| BEXLEY CITY PWS | OH2500103 | 14,250 | Surface water purchased | 2 | Below the study levels |
| BLANCHESTER VILLAGE PWS | OH1400111 | 4,243 | Surface water | 1 | Below the study levels |
| BOWLING GREEN CITY | OH8700311 | 31,578 | Surface water | 1 | Below the study levels |
| BRADFORD VILLAGE PWS | OH1900212 | 2,000 | Ground water | 1 | Below the study levels |
| BROOKVILLE MUNICIPALITY PWS | OH5700203 | 5,923 | Surface water purchased | 1 | Below the study levels |
| BROWN COUNTY RURAL WATER | OH0802012 | 32,090 | Ground water | 1 | Below the study levels |
| BRYAN CITY | OH8600012 | 8,729 | Ground water | 1 | Below the study levels |
| BUCKEYE WATER DISTRICT - OHIO RIVER | OH1502911 | 10,300 | Surface water | 1 | Below the study levels |
| BUCYRUS CITY | OH1700011 | 12,570 | Surface water | 1 | Below the study levels |
| BUTLER CO. WATER DISTRICT 2 PWS | OH0900303 | 116,572 | Surface water purchased | 2 | Below the study levels |
| BYESVILLE | OH3001212 | 5,104 | Groundwater under influence of surface water | 1 | Below the study levels |
| CADIZ VILLAGE PWS | OH3400214 | 3,353 | Surface water | 1 | Below the study levels |
| CAMBRIDGE, CITY OF | OH3000111 | 10,520 | Surface water | 1 | Reached a study level |
| CANAL WINCHESTER CITY PWS | OH2500312 | 9,286 | Ground water | 1 | Below the study levels |
| CANFIELD CITY PWS | OH5000503 | 7,706 | Surface water purchased | 1 | Reached a study level |
| CANTON PUBLIC WATER SYSTEM | OH7608112 | 107,113 | Ground water | 3 | Below the study levels |
| CAREY VILLAGE | OH8800012 | 3,674 | Ground water | 1 | Below the study levels |
| CEDARVILLE UNIVERSITY | OH2903612 | 4,000 | Ground water | 1 | Below the study levels |
| CELINA CITY | OH5400011 | 11,682 | Surface water | 1 | Below the study levels |
| CHAGRIN FALLS VILLAGE PWS | OH1800212 | 4,991 | Surface water purchased | 2 | Below the study levels |
| CHARDON CITY PWS | OH2800412 | 5,247 | Ground water | 1 | Below the study levels |
| CHILLICOTHE CITY PWS | OH7100112 | 21,725 | Ground water | 1 | Below the study levels |
| CHILLICOTHE CORRECTIONAL INSTITUTION | OH7101212 | 9,000 | Ground water | 1 | Below the study levels |
| CINCINNATI PUBLIC WATER SYSTEM | OH3102612 | 750,200 | Surface water | 2 | Reached a study level |
| CIRCLEVILLE CITY PWS | OH6500412 | 13,927 | Ground water | 1 | Below the study levels |
| CITY OF HEATH PWS | OH4500912 | 10,310 | Ground water | 1 | Below the study levels |
| CLARK COUNTY GREEN MEADOWS 2 PWS | OH1200703 | 3,008 | Ground water purchased | 1 | Below the study levels |
| CLARK COUNTY NORTHRIDGE PWS | OH1201003 | 8,874 | Ground water purchased | 1 | Below the study levels |
| CLARK COUNTY PARK LAYNE PWS | OH1201112 | 4,221 | Ground water | 1 | Below the study levels |
| CLERMONT PUBLIC WATER SYSTEM | OH1302212 | 133,059 | Surface water | 3 | Reached a study level |
| CLEVELAND PUBLIC WATER SYSTEM | OH1801212 | 1,308,955 | Surface water | 4 | Below the study levels |
| CLEVES VILLAGE PWS | OH3100512 | 6,000 | Ground water | 1 | Below the study levels |
| COLDWATER VILLAGE | OH5400112 | 4,774 | Ground water | 1 | Below the study levels |
| COLUMBIANA CITY PWS | OH1500312 | 6,727 | Ground water | 1 | Below the study levels |
| COLUMBUS GROVE VILLAGE | OH6900112 | 2,137 | Ground water | 1 | Below the study levels |
| COLUMBUS PUBLIC WATER SYSTEM | OH2504412 | 1,305,946 | Surface water | 3 | Below the study levels |
| COMMERCIAL POINT VILLAGE | OH6503512 | 3,497 | Ground water | 1 | Below the study levels |
| CONNEAUT | OH0400411 | 12,538 | Surface water | 1 | Below the study levels |
| CORTLAND CITY PWS | OH7800512 | 7,105 | Ground water | 3 | Below the study levels |
| COSHOCTON PWS | OH1600012 | 13,537 | Ground water | 1 | Below the study levels |
| CRESTLINE VILLAGE | OH1700112 | 4,525 | Ground water | 1 | Below the study levels |
| CUYAHOGA FALLS CITY PWS | OH7701012 | 51,114 | Ground water | 1 | Below the study levels |
| DAYTON PUBLIC WATER SYSTEM | OH5703512 | 141,407 | Surface water | 2 | Reached a study level |
| DAYTON VA BLDG 410 | OH5750618 | 125 | Surface water purchased | 1 | Reached a study level |
| DEFIANCE CITY | OH2000111 | 16,494 | Surface water | 1 | Below the study levels |
| DEL-CO WATER COMPANY, INC. | OH2101412 | 150,000 | Surface water | 3 | Below the study levels |
| DELAWARE CITY PWS | OH2100311 | 43,895 | Surface water | 1 | Below the study levels |
| DELPHOS CITY | OH0200412 | 7,101 | Surface water | 1 | Below the study levels |
| DELTA VILLAGE | OH2600311 | 3,518 | Surface water | 1 | Below the study levels |
| DOVER CITY PWS | OH7900412 | 13,253 | Ground water | 1 | Below the study levels |
| EARNHART HILL WATER DISTRICT PWS | OH6500812 | 10,057 | Ground water | 1 | Below the study levels |
| EAST LIVERPOOL CITY | OH1500811 | 12,586 | Surface water | 1 | Below the study levels |
| EAST PALESTINE VILLAGE PWS | OH1500912 | 4,761 | Ground water | 1 | Below the study levels |
| EATON PUBLIC WATER SYSTEM | OH6801612 | 8,400 | Ground water | 2 | Below the study levels |
| ELIDA VILLAGE | OH0200503 | 4,109 | Surface water purchased | 1 | Below the study levels |
| ELYRIA WATER DEPARTMENT | OH4700411 | 68,000 | Surface water | 1 | Below the study levels |
| ENGLEWOOD CITY PWS | OH5700812 | 13,463 | Ground water | 1 | Below the study levels |
| FAIRBORN PUBLIC WATER SYSTEM | OH2900612 | 34,620 | Ground water | 1 | Below the study levels |
| FAIRFIELD CITY PWS | OH0900715 | 44,907 | Ground water | 1 | Below the study levels |
| FAIRFIELD COUNTY UTILITIES PWS | OH2301912 | 15,486 | Ground water | 1 | Below the study levels |
| FELICITY VILLAGE PWS | OH1300612 | 1,573 | Ground water | 1 | Below the study levels |
| FINDLAY CITY | OH3200111 | 54,040 | Surface water | 1 | Below the study levels |
| FOSTORIA CITY | OH7400411 | 13,441 | Surface water | 1 | Below the study levels |
| FRANKLIN PUBLIC WATER SYSTEM | OH8300412 | 11,690 | Ground water | 1 | Below the study levels |
| FREMONT CITY | OH7200311 | 18,319 | Surface water | 1 | Below the study levels |
| GAHANNA CITY PWS | OH2501303 | 33,258 | Surface water purchased | 1 | Below the study levels |
| GALION CITY | OH1700211 | 10,453 | Surface water | 1 | Below the study levels |
| GALLIA CO RURAL WATER ASSOCIATION | OH2700012 | 20,995 | Ground water | 1 | Reached a study level |
| GENEVA CITY PWS | OH0401712 | 5,924 | Surface water purchased | 1 | Below the study levels |
| GEORGETOWN VILLAGE PWS | OH0800503 | 4,331 | Ground water purchased | 1 | Below the study levels |
| GERMANTOWN CITY PWS | OH5701012 | 5,547 | Ground water | 1 | Below the study levels |
| GNADENHUTTEN PWS | OH7900512 | 1,240 | Ground water | 1 | Below the study levels |
| GREENE CO.-NORTHWEST REG WATER | OH2903512 | 41,895 | Ground water | 2 | Below the study levels |
| GREENE COUNTY EASTERN REGIONAL PWS | OH2906103 | 4,800 | Ground water purchased | 1 | Below the study levels |
| GREENFIELD TWP WATER DISTRICT | OH2301812 | 490 | Ground water | 1 | Below the study levels |
| GREENFIELD VILLAGE PWS | OH3600312 | 4,600 | Ground water | 1 | Below the study levels |
| GROVEPORT PWS | OH2501512 | 3,229 | Ground water | 1 | Below the study levels |
| HAMILTON PUBLIC WATER SYSTEM | OH0904012 | 62,447 | Ground water | 2 | Below the study levels |
| HARRISON CITY PWS | OH3100812 | 11,600 | Ground water | 1 | Below the study levels |
| HECLA WATER ASSOCIATION-PLANT PWS | OH4401612 | 34,942 | Surface water purchased | 2 | Below the study levels |
| HICKSVILLE VILLAGE | OH2000212 | 3,600 | Ground water | 1 | Below the study levels |
| HIGHLAND COUNTY WATER COMPANY, INC. | OH3600514 | 28,421 | Ground water | 1 | Below the study levels |
| HUBBARD CITY PWS | OH7801415 | 8,518 | Surface water purchased | 1 | Below the study levels |
| HUBER HEIGHTS PUBLIC WATER SYSTEM | OH5703612 | 43,439 | Ground water | 1 | Below the study levels |
| HUDSON CITY PWS | OH7701612 | 8,385 | Ground water | 1 | Below the study levels |
| HURON CITY | OH2201011 | 6,893 | Surface water | 1 | Below the study levels |
| I-71 AND SR-35 PWS | OH2437412 | 7,685 | Surface water | 1 | Below the study levels |
| INDIAN HILL CITY PWS | OH3101112 | 15,000 | Ground water | 1 | Reached a study level |
| IRONTON PWS | OH4400711 | 11,129 | Surface water | 1 | Below the study levels |
| JACKSON CO. WATER COMPANY-WTP | OH4002012 | 15,984 | Ground water | 1 | Below the study levels |
| JACKSON, CITY OF | OH4000111 | 9,691 | Surface water | 1 | Below the study levels |
| JEFFERSON REGIONAL WATER AUTHORITY | OH5703012 | 4,813 | Ground water | 1 | Below the study levels |
| JEFFERSON WATER AND SEWER DISTRICT PWS | OH2504012 | 11,294 | Ground water | 1 | Below the study levels |
| JOHNSTOWN VILLAGE PWS | OH4501512 | 5,200 | Ground water | 1 | Below the study levels |
| KENT CITY PWS | OH6701812 | 29,662 | Ground water | 1 | Below the study levels |
| KENTON CITY | OH3300612 | 8,360 | Ground water | 1 | Below the study levels |
| KNOX COUNTY WATER AND WASTEWATER PWS | OH4202012 | 7,710 | Ground water | 1 | Below the study levels |
| LAKE COUNTY EAST WATER SUBDISTRICT | OH4302911 | 40,656 | Surface water | 1 | Below the study levels |
| LAKE COUNTY WEST WATER SUBDISTRICT | OH4302411 | 78,379 | Surface water | 1 | Below the study levels |
| LAKEWOOD CITY PWS | OH1801003 | 50,942 | Surface water purchased | 1 | Below the study levels |
| LANCASTER CITY PWS | OH2301012 | 40,400 | Ground water | 2 | Below the study levels |
| LE-AX REGIONAL WATER DISTRICT PWS | OH0501111 | 19,311 | Ground water | 1 | Below the study levels |
| LEADING CREEK CONSERVANCY DISTRICT | OH5300012 | 6,663 | Ground water | 1 | Reached a study level |
| LEBANON CITY | OH8304112 | 20,700 | Surface water purchased | 1 | Below the study levels |
| LEBANON CORRECTIONAL INSTITUTION | OH8301012 | 3,410 | Ground water | 1 | Below the study levels |
| LEXINGTON VILLAGE | OH7002212 | 4,825 | Ground water | 1 | Below the study levels |
| LIMA CITY | OH0200811 | 65,619 | Surface water | 1 | Below the study levels |
| LITTLE HOCKING WATER ASSOCIATION, INC. | OH8400212 | 9,892 | Ground water | 1 | Below the study levels |
| LOCKLAND VILLAGE PWS | OH3101212 | 3,486 | Ground water | 1 | Below the study levels |
| LOGAN, CITY OF | OH3700612 | 6,704 | Ground water | 1 | Below the study levels |
| LONDON CITY PWS | OH4900712 | 10,256 | Ground water | 1 | Below the study levels |
| LORAIN CITY PWS | OH4700711 | 64,152 | Surface water | 1 | Below the study levels |
| LORDSTOWN VILLAGE PWS | OH7804403 | 3,515 | Surface water purchased | 1 | Reached a study level |
| LOUISVILLE CITY PWS | OH7603012 | 9,186 | Ground water | 1 | Below the study levels |
| LOVELAND CITY PWS | OH1300812 | 12,800 | Ground water | 1 | Reached a study level |
| MADISON COUNTY SSWD WATER DISTRICT 1 | OH4901012 | 5,176 | Ground water | 1 | Below the study levels |
| MALVERN VILLAGE PWS | OH1000112 | 1,200 | Ground water | 1 | Below the study levels |
| MANSFIELD CITY | OH7002914 | 51,000 | Surface water | 1 | Below the study levels |
| MARIETTA CITY PWS | OH8400412 | 18,707 | Ground water | 1 | Reached a study level |
| MAUMEE CITY | OH4800603 | 14,286 | Surface water purchased | 1 | Below the study levels |
| MAYSVILLE REGIONAL WATER | OH6001411 | 6,540 | Ground water purchased | 1 | Below the study levels |
| MCDONALD VILLAGE PWS | OH7802003 | 4,236 | Surface water purchased | 1 | Reached a study level |
| MEDINA CITY PWS | OH5200514 | 25,956 | Surface water purchased | 1 | Below the study levels |
| MEDINA CO/SOUTHERN WATER DIST PWS | OH5260712 | 4,708 | Ground water | 2 | Below the study levels |
| MIAMI CO-CAMP TROY PWS | OH5502503 | 3,742 | Ground water purchased | 1 | Below the study levels |
| MIAMISBURG CITY PWS | OH5701212 | 19,790 | Ground water | 1 | Below the study levels |
| MID-OHIO WSD PLAIN CITY WTP | OH4901112 | 4,467 | Ground water | 1 | Below the study levels |
| MIDDLETOWN CITY PWS | OH0901712 | 51,229 | Ground water | 1 | Below the study levels |
| MILFORD CITY PWS | OH1301012 | 6,700 | Ground water | 1 | Reached a study level |
| MILLERSBURG VILLAGE PWS | OH3800912 | 3,151 | Ground water | 1 | Below the study levels |
| MINERVA VILLAGE PWS | OH7603812 | 3,684 | Ground water | 1 | Below the study levels |
| MONROE CITY PWS, OH | OH0902012 | 15,600 | Surface water purchased | 1 | Below the study levels |
| MONROE WATER SYSTEMS | OH5600812 | 4,334 | Ground water | 1 | Below the study levels |
| MONTGOMERY COUNTY WATER SERVICES 1 PWS | OH5701315 | 150,207 | Surface water purchased | 1 | Reached a study level |
| MONTGOMERY COUNTY WATER SERVICES 2 PWS | OH5701503 | 83,033 | Surface water purchased | 1 | Below the study levels |
| MONTPELIER VILLAGE | OH8600912 | 4,280 | Ground water | 1 | Below the study levels |
| MOUNT ORAB VILLAGE PWS | OH0801011 | 6,607 | Surface water | 1 | Below the study levels |
| MOUNT VERNON CITY PWS | OH4200812 | 16,990 | Ground water | 1 | Below the study levels |
| MT GILEAD VILLAGE PWS | OH5900712 | 3,503 | Ground water | 1 | Below the study levels |
| MUNROE FALLS CITY PWS | OH7702703 | 5,042 | Ground water purchased | 1 | Below the study levels |
| MUSKINGUM COUNTY WATER - SE | OH6000412 | 21,540 | Ground water | 1 | Below the study levels |
| NAPOLEON CITY | OH3500811 | 8,858 | Surface water | 1 | Below the study levels |
| NAWA | OH5553612 | 29,974 | Ground water | 1 | Below the study levels |
| NELSONVILLE PWS | OH0501214 | 6,656 | Ground water | 1 | Below the study levels |
| NEW BREMEN VILLAGE | OH0600512 | 3,034 | Ground water | 1 | Below the study levels |
| NEW CARLISLE CITY PWS | OH1203312 | 5,800 | Ground water | 1 | Below the study levels |
| NEW LEBANON VILLAGE PWS | OH5701812 | 3,770 | Ground water | 1 | Below the study levels |
| NEW LEXINGTON | OH6400411 | 5,161 | Surface water | 1 | Below the study levels |
| NEW MIAMI VILLAGE PWS | OH0902112 | 3,200 | Ground water | 1 | Below the study levels |
| NEW PHILADELPHIA CITY PWS | OH7900812 | 17,410 | Ground water | 1 | Below the study levels |
| NEWARK CITY PWS | OH4502314 | 49,934 | Surface water | 1 | Below the study levels |
| NEWCOMERSTOWN VILLAGE PWS | OH7900912 | 3,882 | Ground water | 1 | Below the study levels |
| NEWTON FALLS CITY | OH7802311 | 6,109 | Surface water | 1 | Reached a study level |
| NORTH CANTON CITY PWS | OH7604312 | 24,747 | Ground water | 1 | Below the study levels |
| NORTH RIDGEVILLE CITY PWS | OH4700803 | 29,465 | Surface water purchased | 2 | Below the study levels |
| NORTHERN OHIO RURAL WATER | OH3902403 | 18,224 | Surface water purchased | 4 | Below the study levels |
| NORTHERN OHIO RURAL WATER - NW DISTRICT | OH2201803 | 6,409 | Surface water purchased | 1 | Below the study levels |
| NORTHWEST REGIONAL WATER DISTRICT | OH7300003 | 11,059 | Ground water purchased | 1 | Below the study levels |
| NORTHWESTERN W AND SD - WTLN 200 | OH8704203 | 9,629 | Surface water purchased | 1 | Below the study levels |
| NORTHWESTERN W AND SD -TOLEDO SVCE AREA | OH8752812 | 19,758 | Surface water purchased | 1 | Below the study levels |
| NORTHWESTERN W AND SD- PORTAGE | OH8704103 | 4,776 | Surface water purchased | 1 | Below the study levels |
| NORW - SOUTH DISTRICT | OH3946712 | 5,226 | Surface water purchased | 1 | Below the study levels |
| NORWALK CITY | OH3901111 | 17,466 | Surface water | 1 | Below the study levels |
| NORWOOD CITY PWS | OH3101703 | 19,870 | Surface water purchased | 1 | Below the study levels |
| OAK HARBOR VILLAGE | OH6202603 | 4,400 | Surface water purchased | 1 | Below the study levels |
| OAKDALE WATER DISTRICT | OH6402403 | 250 | Ground water purchased | 1 | Below the study levels |
| OAKWOOD CITY PWS | OH5701915 | 9,572 | Ground water | 2 | Below the study levels |
| OBERLIN WATER DEPARTMENT | OH4700911 | 8,600 | Surface water | 1 | Below the study levels |
| ODRC-PICKAWAY CORRECTION PWS | OH6501712 | 3,376 | Ground water | 1 | Below the study levels |
| ONTARIO CITY | OH7003512 | 6,756 | Ground water | 1 | Below the study levels |
| OREGON CITY, OH | OH4800911 | 19,950 | Surface water | 1 | Below the study levels |
| ORRVILLE CITY PWS | OH8502712 | 8,452 | Ground water | 1 | Below the study levels |
| OTTAWA COUNTY REGIONAL WATER DISTRICT | OH6205011 | 20,428 | Surface water | 1 | Below the study levels |
| OTTAWA VILLAGE | OH6900711 | 4,393 | Surface water | 1 | Below the study levels |
| OXFORD CITY PWS | OH0902312 | 24,000 | Ground water | 1 | Below the study levels |
| PAINESVILLE CITY PWS | OH4301611 | 31,728 | Surface water | 1 | Below the study levels |
| PATASKALA CITY | OH4502512 | 9,900 | Ground water | 2 | Below the study levels |
| PAULDING VILLAGE | OH6300411 | 3,605 | Surface water | 1 | Below the study levels |
| PERRYSBURG CITY WATER | OH8701803 | 27,000 | Surface water purchased | 1 | Below the study levels |
| PICKERINGTON CITY PWS | OH2301512 | 19,141 | Ground water | 1 | Below the study levels |
| PIKE WATER, INC.-PLANT PWS | OH6602412 | 15,487 | Ground water | 1 | Below the study levels |
| PIQUA CITY PWS | OH5501211 | 20,354 | Surface water | 1 | Below the study levels |
| PORT CLINTON CITY | OH6203211 | 6,500 | Surface water purchased | 1 | Below the study levels |
| PORTAGE COUNTY WATER RESOURCES | OH6702812 | 8,606 | Ground water | 2 | Below the study levels |
| PORTSMOUTH PUBLIC WATER SYSTEM | OH7300111 | 40,475 | Surface water | 1 | Below the study levels |
| PUTNAM COMMUNITY WATER ASSOCIATION PWS | OH8400712 | 2,744 | Ground water | 1 | Reached a study level |
| RAVENNA CITY PWS | OH6703211 | 16,000 | Surface water | 1 | Below the study levels |
| READING CITY PWS | OH3101812 | 9,506 | Surface water purchased | 1 | Below the study levels |
| REYNOLDSBURG CITY PWS | OH2503203 | 37,847 | Surface water purchased | 2 | Below the study levels |
| RITTMAN CITY PWS | OH8503012 | 6,491 | Ground water | 2 | Below the study levels |
| ROSS COUNTY WATER CO INC PWS | OH7101412 | 35,345 | Ground water | 2 | Below the study levels |
| RURAL LORAIN CO. WATER A | OH4701803 | 73,125 | Surface water purchased | 3 | Below the study levels |
| SALEM CITY, OH | OH1502011 | 16,850 | Surface water | 1 | Below the study levels |
| SANDUSKY CITY | OH2201411 | 25,793 | Surface water | 1 | Below the study levels |
| SANITARY DISTRICT #4 | OH2501003 | 8,575 | Surface water purchased | 1 | Below the study levels |
| SCIOTO CO. REGIONAL WATER DISTRICT #1 | OH7300212 | 13,820 | Ground water | 1 | Below the study levels |
| SCIOTO WATER, INC.-ROSE HILL | OH7300303 | 8,861 | Ground water | 1 | Below the study levels |
| SCRANTON WOODS | OH2803712 | 114 | Ground water | 1 | Below the study levels |
| SHADYSIDE PUBLIC WATER SYSTEM | OH0701612 | 3,689 | Ground water | 1 | Reached a study level |
| SHEFFIELD LAKE CITY PWS | OH4701103 | 9,108 | Surface water purchased | 1 | Below the study levels |
| SHELBY CITY | OH7004511 | 9,453 | Surface water | 1 | Below the study levels |
| SIDNEY CITY PWS | OH7501214 | 20,614 | Surface water | 1 | Below the study levels |
| SOUTH LEBANON VILLAGE PWS | OH8301312 | 3,891 | Surface water purchased | 1 | Below the study levels |
| SOUTH POINT VILLAGE | OH4401212 | 4,133 | Ground water | 1 | Below the study levels |
| SOUTHERN PERRY CO-CONGO | OH6401603 | 4,029 | Ground water purchased | 1 | Below the study levels |
| SOUTHWEST LICKING COMMUNITY WATER | OH4505412 | 17,818 | Ground water | 1 | Below the study levels |
| SOUTHWEST REGIONAL WATER DISTRICT | OH0903912 | 42,856 | Ground water | 2 | Below the study levels |
| SPRINGBORO PWS | OH8301412 | 19,263 | Ground water | 1 | Reached a study level |
| SPRINGFIELD CITY PWS | OH1204412 | 60,680 | Ground water | 1 | Below the study levels |
| ST MARYS CITY | OH0600612 | 9,356 | Ground water | 1 | Below the study levels |
| ST. CLAIRSVILLE, CITY OF PWS | OH0701516 | 5,097 | Surface water | 1 | Reached a study level |
| STARK COUNTY WATER DISTRICT | OH7607303 | 6,690 | Ground water purchased | 1 | Below the study levels |
| STEUBENVILLE, CITY OF | OH4102411 | 17,000 | Surface water | 1 | Below the study levels |
| STOW PUBLIC WATER SYSTEM | OH7704503 | 35,437 | Surface water purchased | 1 | Below the study levels |
| STREETSBORO CITY PWS | OH6705003 | 15,105 | Ground water purchased | 1 | Below the study levels |
| SWANTON VILLAGE | OH2601011 | 3,855 | Surface water | 1 | Below the study levels |
| SYLVANIA CITY | OH4801303 | 21,618 | Surface water purchased | 1 | Below the study levels |
| TALLMADGE CITY PWS | OH7704703 | 18,394 | Surface water purchased | 1 | Below the study levels |
| TATE-MONROE WATER ASSOCIATION PWS | OH1301312 | 24,092 | Ground water | 2 | Below the study levels |
| TCMSD-WILKSHIRE HILLS PWS | OH7901612 | 6,587 | Ground water | 1 | Below the study levels |
| TIMBERLAKE WATER SYSTEM | OH2501812 | 1,600 | Ground water | 1 | Below the study levels |
| TOLEDO, CITY OF | OH4801411 | 360,000 | Surface water | 1 | Below the study levels |
| TORONTO PWS | OH4102811 | 5,676 | Surface water | 1 | Below the study levels |
| TRENTON CITY PWS | OH0903012 | 13,012 | Ground water | 1 | Below the study levels |
| TROTWOOD CITY PWS | OH5702403 | 9,000 | Surface water purchased | 1 | Below the study levels |
| TROY CITY PWS, OH | OH5501612 | 26,305 | Ground water | 1 | Below the study levels |
| TRUMBULL CO. - BAZETTA/CHAMPION | OH7804303 | 8,270 | Surface water purchased | 1 | Below the study levels |
| TRUMBULL CO.-HOWLAND TWP PWS | OH7806303 | 6,396 | Surface water purchased | 1 | Reached a study level |
| TRUMBULL CO.-SOUTHEAST PWS | OH7803203 | 9,931 | Surface water purchased | 1 | Reached a study level |
| TUPPER PLAINS/CHESTER WATER DISTRICT | OH5300612 | 16,087 | Ground water | 1 | Below the study levels |
| TWIN CITY WATER AND SEWER DISTRICT PWS | OH7901711 | 9,224 | Ground water | 1 | Below the study levels |
| UNION CITY PWS | OH5702512 | 7,000 | Ground water | 2 | Below the study levels |
| URBANA CITY PWS | OH1101212 | 11,428 | Ground water | 2 | Below the study levels |
| VAN WERT CITY | OH8100611 | 10,846 | Surface water | 1 | Below the study levels |
| VERMILION CITY | OH2201511 | 10,594 | Surface water | 1 | Below the study levels |
| WADSWORTH CITY PWS | OH5201712 | 24,356 | Ground water | 1 | Below the study levels |
| WAPAKONETA CITY | OH0600712 | 11,000 | Ground water | 1 | Below the study levels |
| WARREN CITY PWS | OH7803811 | 49,130 | Surface water | 1 | Below the study levels |
| WARREN CO. RICHARD RENNEKER PWS | OH8301512 | 81,975 | Ground water | 1 | Below the study levels |
| WARREN CO. SOCIALVILLE PWS | OH8304203 | 13,216 | Surface water purchased | 1 | Below the study levels |
| WARREN COMM W AND S ASSN 2 | OH8402703 | 7,215 | Ground water | 1 | Reached a study level |
| WASHINGTON COURT HOUSE PWS | OH2400714 | 14,100 | Surface water | 1 | Below the study levels |
| WATERFORD WATER/SEWER ASSOCIATION | OH8401112 | 770 | Ground water | 1 | Below the study levels |
| WATERVILLE CITY | OH4801503 | 6,500 | Surface water purchased | 1 | Below the study levels |
| WAVERLY CITY PWS | OH6600912 | 4,433 | Ground water | 1 | Below the study levels |
| WAYNESVILLE VILLAGE PWS | OH8302012 | 4,100 | Ground water | 1 | Below the study levels |
| WAYNOKA REGIONAL WATER AND SEWER DIST | OH0800811 | 2,428 | Surface water | 3 | Below the study levels |
| WELLINGTON VILLAGE PWS | OH4701511 | 4,802 | Surface water | 1 | Below the study levels |
| WELLSTON CITY PWS | OH4001912 | 5,846 | Surface water | 2 | Below the study levels |
| WEST CARROLLTON CITY PWS | OH5702812 | 8,361 | Ground water | 1 | Below the study levels |
| WEST JEFFERSON VILLAGE PWS | OH4902012 | 4,488 | Ground water | 1 | Below the study levels |
| WEST MILTON VILLAGE PWS | OH5501711 | 4,890 | Ground water purchased | 1 | Below the study levels |
| WESTERN WATER COMPANY | OH8300512 | 39,508 | Surface water purchased | 2 | Reached a study level |
| WESTERVILLE CITY PWS | OH2503411 | 39,000 | Surface water | 1 | Below the study levels |
| WHITEHOUSE VILLAGE | OH4801612 | 5,200 | Surface water purchased | 2 | Below the study levels |
| WILLARD CITY | OH3901511 | 7,099 | Surface water | 1 | Below the study levels |
| WILMINGTON CITY PWS | OH1401211 | 12,401 | Surface water | 1 | Below the study levels |
| WOOSTER CITY PWS | OH8504512 | 26,618 | Ground water | 1 | Below the study levels |
| WRIGHT STATE UNIVERSITY | OH2902012 | 8,948 | Ground water | 1 | Below the study levels |
| WRIGHT-PATTERSON AFB AREA A PWS | OH2903412 | 16,551 | Ground water | 4 | Reached a study level |
| WRIGHT-PATTERSON AFB AREA B PWS | OH2903312 | 11,034 | Ground water | 2 | Reached a study level |
| XENIA CITY PWS | OH2902812 | 29,000 | Ground water | 1 | Below the study levels |
| YELLOW SPRINGS VILLAGE PWS | OH2903012 | 3,761 | Ground water | 1 | Reached a study level |
| ZANESVILLE PWS | OH6002712 | 29,381 | Ground water | 1 | Below the study levels |
How the count works
What is included
Each active community water system with complete monitoring is counted once, even if it is linked with several ZIP codes. Private wells are excluded, and UCMR 5 did not comprehensively monitor every small system. This page does not apply Ohio's state-specific standards or determine compliance. Use the official state or territory drinking-water program for current regulatory information.