Pennsylvania Well Water: Top Contaminants & Testing Guide
2026-03-20 · 6 min read · State Guide
Pennsylvania Well Water Landscape
Over one million Pennsylvania households rely on private wells. The state has diverse geology that creates varying water quality challenges across different regions.
Top Contaminants
Radon: PA has some of the highest indoor radon levels in the nation, and well water contributes to indoor air exposure. Coliform bacteria: Common in rural areas with agricultural activity and aging septic systems. Lead: Older homes with lead solder and service lines. Nitrate: Agricultural areas in central and southeastern PA.
PA Regulations
Pennsylvania does not require private well testing except at the time of property transfer in some counties. The PA DEP recommends annual testing for bacteria and nitrate, and periodic testing for other contaminants.
Resources
Penn State Extension offers water testing through their Agricultural Analytical Services Lab at competitive prices. Contact your county conservation district for local guidance. See all Pennsylvania well water data.
Our team analyzes data from EPA SDWIS & USGS to deliver accurate, up-to-date information. All data is verified and cross-referenced with official sources.