CRC Roundtable -- June 2025

A River Runs Orange: Acid Mine Drainage in the Chesapeake Bay Watershed If your local waterway looks more “rusty” than usual, acid mine drainage may be to blame. Acid mine drainage (AMD) occurs when groundwater carries toxic metals from abandoned mine sites into streams and rivers, often turning them an alarming shade of orange. The acidic conditions degrade water quality, damage ecosystems, and complicate restoration efforts downstream–particularly those related to phosphorus management. Options to reduce AMD range from passive natural systems such as wetlands to active systems similar to water treatment plants. During June's CRC Roundtable, we explored the origins, impacts, and remediation efforts to address AMD pollution.