Free Ohio water report: PFAS & lead levels for every water system, worst-affected cities, and EPA violations. Check your ZIP.
Ohio's 11.8 million residents rely on a mix of surface water from Lake Erie, the Ohio River, and inland reservoirs, plus groundwater from aquifers across the state. Cleveland, Toledo, and other lakefront cities draw from Lake Erie, while Cincinnati draws from the Ohio River and Columbus uses a combination of reservoirs and wells. The Ohio Environmental Protection Agency (Ohio EPA) oversees drinking water compliance in a state with a complicated environmental legacy. Decades of heavy industry, manufacturing, and agricultural activity have left their mark on Ohio's water sources, and PFAS contamination adds the latest chapter to a long industrial contamination history.
The most prominent military PFAS source in Ohio is Wright-Patterson Air Force Base near Dayton. One of the largest and oldest Air Force installations in the country, Wright-Patterson has confirmed PFAS contamination in groundwater from AFFF use. The base's proximity to residential areas and local water supplies in Greene and Montgomery counties has prompted Department of Defense investigations and community concern.
Beyond military sources, Ohio's industrial legacy contributes significant PFAS contamination. Manufacturing facilities in the Dayton, Toledo, and Cleveland areas used PFAS-containing products in various industrial processes. The state has identified multiple sites where industrial PFAS has reached groundwater or surface water.
Lake Erie presents its own water quality challenges. While PFAS is one concern, the lake has been plagued by harmful algal blooms (HABs) driven by agricultural nutrient runoff from the western basin. In 2014, a severe algal bloom in western Lake Erie produced microcystin toxin that forced Toledo to issue a do-not-drink advisory for over 400,000 residents – one of the largest drinking water emergencies in recent US history. Algal toxins and PFAS are different contaminant classes, but they compound the treatment burden for Lake Erie utilities.
Ohio has not adopted state-specific PFAS MCLs, relying on the federal EPA standards of 4 parts per trillion for PFOA and PFOS finalized in 2024. The UCMR5 testing program has documented detections across numerous Ohio water systems, and our data integrates federal, state, and utility-level monitoring for address-specific results.
Ohio sits in the middle of the pack on PFAS regulation – more aware of the problem than many states but less aggressive than leaders like New Jersey or Michigan on enforcement and standards. The state's industrial contamination legacy means PFAS is one of many contaminant classes that Ohio EPA is managing simultaneously, including PCBs, volatile organic compounds, and heavy metals from Superfund sites across the industrial Midwest.
Compared to neighboring states, Ohio faces a more diverse set of water quality challenges than most. Michigan has moved faster on PFAS regulation, Pennsylvania has been more aggressive on testing, and Indiana faces similar industrial legacy issues but with a smaller population. Ohio's Lake Erie algal bloom problem is regionally unique and adds a layer of water quality concern that most states do not share.
The Toledo water crisis of 2014 demonstrated what happens when agricultural contamination overwhelms treatment capacity, and it catalyzed state and federal investment in Lake Erie monitoring and nutrient reduction programs.
Ohio's water quality depends on your source – Lake Erie, the Ohio River, a local reservoir, or groundwater – and on the industrial and agricultural history of your specific area.
1. Check your water quality using our free lookup tool. We map UCMR5 data, Ohio EPA monitoring, and utility reports to your ZIP code so you see what is relevant for your home. 2. If PFAS or other contaminants are detected, a reverse osmosis system provides the broadest protection – over 90% removal for most PFAS compounds and effective reduction of many other contaminants. Our water filter guide compares systems by independent lab testing. 3. Private well owners, particularly in the Dayton area near Wright-Patterson AFB or in agricultural regions of western Ohio, should test their water. Request a detailed water report for your address.
For more on PFAS science, see our PFAS guide.
Ohio's water quality history mirrors the rise and fall of the industrial Midwest. The Cuyahoga River, which runs through Cleveland and into Lake Erie, famously caught fire multiple times – the 1969 fire is often credited with catalyzing the modern environmental movement and the creation of the EPA in 1970. The river was so polluted with industrial waste and oil that it was flammable.
Lake Erie was declared "dead" in the 1970s due to eutrophication from phosphorus loading. The Clean Water Act and subsequent nutrient reduction programs brought the lake back from the brink, but the algal bloom problem resurfaced in the 2000s as agricultural practices intensified and dissolved phosphorus from farm runoff proved harder to control than point-source pollution.
Wright-Patterson AFB has been operational since 1917, making it one of the oldest continuously active Air Force installations. Decades of aircraft maintenance, testing, and firefighting training left a contamination footprint that includes PFAS, solvents, and fuels. The base has been on the National Priorities List (Superfund) since 1987, and remediation of various contaminant plumes is ongoing.
Ohio's groundwater contamination extends beyond military sources. The industrial corridors along the Ohio River and through the Miami Valley (Dayton area) accumulated decades of manufacturing waste, much of which reached subsurface aquifers before modern disposal regulations existed. PFAS is the newest addition to this legacy, and the federal MCLs now require Ohio utilities to test for and treat compounds that were not regulated when the contamination occurred. Check your specific address to see the latest monitoring data for your area.