Millimeter by millimeter, Phoenix is sinking lower. It joins nearly every other major city in the nation in experiencing a phenomenon called land subsidence, where the earth’s surface moves downward, according to a study published in the online journal Nature Cities.
The drop, though gradual, could lead to widespread infrastructure damage and flooding, the study warns. The signs of land subsidence are familiar: uneven sidewalks, damage to a building’s foundation, cracked pavement, floors slanting, and doors and windows that don’t close as easily as they once did.
Leonard Ohenhen, a researcher with the Lamont-Doherty Earth Observatory (LDEO) at Columbia University’s Climate School, led the study. He says it found that 1.4 million people in Phoenix are already impacted, with 113,000 buildings labeled medium to high risk and another 172 buildings seen as high risk…