Radar Finds Ground Shifts Under Aging U.S. Dams, Raising Safety Questions

A decade-long Sentinel‑1 radar study flags ground movement beneath several aging U.S. dams, including 41 high-hazard structures over 50 feet tall, with some sections sinking while others rise. While deformation doesn’t mean imminent collapse, it highlights potential weaknesses as climate-driven extreme weather increases stress and maintenance costs rise. The U.S. has about 92,600 dams, more than 2,500 showing damage, and repairing them could cost billions; satellites could help prioritize repairs but aren’t a substitute for inspections.