York County, Maine: drinking water report. York County in southern Maine has about 211,000 residents in communities from Sanford to Kennebunk to Biddeford.
York County in southern Maine has about 211,000 residents in communities from Sanford to Kennebunk to Biddeford. Water sources include surface reservoirs, the Saco River, and groundwater wells. The county's proximity to the former Pease Air Force Base in neighboring New Hampshire and its own agricultural and industrial history create multiple contamination pathways.
PFAS contamination has affected multiple York County communities. The Sanford Seacoast Regional Airport and former military facilities in the area used AFFF. According to Maine DEP's 2024 PFAS investigation, monitoring wells near the Sanford airport showed PFOS at 22 ppt. Agricultural PFAS from biosolids (treated sewage sludge used as fertilizer on farms) has been documented in York County – Maine was among the first states to identify this pathway, and several farms in the county have been found to have PFAS-contaminated soil.
The biosolids pathway is particularly concerning because it contaminated dairy farms, leading to PFAS in milk and groundwater simultaneously. A 2024 Maine CDC study found PFAS in private wells near farms that received biosolids, with some wells showing PFAS above 100 ppt.
York County's PFAS situation is complex because it comes from both military/airport sources and the agricultural biosolids pathway. If you live near a farm that received municipal sludge as fertilizer, your well may be affected even if you are far from any military installation.
Check your water for available data. For PFAS at any level, reverse osmosis provides the highest removal rate. Our water filter guide covers systems with certified PFAS performance. Pull your detailed report for local data, and visit our Maine page for statewide context.