Erie County, Ohio: drinking water report. Erie County sits on Lake Erie's south shore in north-central Ohio, with Sandusky as the county seat and about…
Erie County sits on Lake Erie's south shore in north-central Ohio, with Sandusky as the county seat and about 75,000 residents. The county draws drinking water from Lake Erie, with the City of Sandusky and Huron operating separate intake and treatment systems. The western Lake Erie basin is ground zero for the lake's recurring harmful algal bloom problem, and Erie County sits right at the transition between the bloom-prone western basin and the cleaner central basin.
Harmful algal blooms in western Lake Erie have intensified over the past decade. According to NOAA's 2024 Lake Erie HAB forecast, the 2024 bloom severity index reached 6.8 on a 10-point scale – classified as moderate-to-significant. Microcystin, the primary toxin of concern, was detected in raw water at the Sandusky intake at concentrations up to 4.2 ug/L during peak bloom season, requiring enhanced treatment to bring finished water below the 1.0 ug/L standard.
The EPA's UCMR5 data also shows PFAS detections in Erie County water systems. NASA's Plum Brook Station, a former rocket testing facility in the county, used AFFF during fire suppression activities. Ohio EPA's 2024 investigation documented PFAS in monitoring wells near the facility at 16 ppt combined.
Algal bloom season – typically July through October – is when Erie County's source water faces the most stress. Treatment plants have invested in advanced oxidation and activated carbon to manage microcystin, but a household carbon filter provides an additional buffer during peak months.
Check your water for current and seasonal data. For both microcystin and PFAS, a reverse osmosis system under the sink addresses both. Our water filter guide ranks systems by real-world performance. Pull your detailed report for seasonal trends, and visit our Ohio page for statewide context.
Drinking water is one exposure route. These federal datasets also cover Erie County, OH.
The EPA places Erie County, OH in Zone 2 - a moderate-risk category, with a predicted average indoor radon level between 2 and 4 pCi/L. Zone maps predict an area's radon potential from geology and existing indoor readings; they say nothing about a specific house. Testing is the only way to know your own level.
72% of homes in Erie County, OH were built before 1980, and 29% before 1950. Residential lead paint was banned in 1978, so housing age is the strongest available proxy for lead-paint exposure. This describes the county's housing stock, not any one home.
Modelled annual fine-particle pollution (PM2.5) in Erie County, OH averages 8.1 µg/m³, within the EPA's annual standard of 9 µg/m³. These are CDC modelled county estimates rather than readings from a specific monitor.
How radon zones work · Air quality by county · Lead exposure guide