From a new book by Alan Weisman.
If people vanished from New York:
in 10 years...sidewalks crack, weeds invade. Rat population, deprived of garbage, crashes. Cockroaches, which thrive in warm buildings, disappear.
in 20 years...water soaked steel columns supporting subway tunnels corrode and buckle. Bears and wolves invade Central Park.
in 50 years...Concrete chunks tumble from buildings, whose steel foundations begin to crumble. Indian Point nuclear reactors leak radioactivity into the Hudson River.
in 100 years...Oaks and maples re-cover the land
in 300 years...most bridges collapse
in 1000 years, Hell Gate Bridge, built to bring the railroad across the East River, finally falls.
in 10,000 years...Indian Point reactor continues to leak radioactivity into the Hudson.
in 20,000 years...Glaciers move relentlessly across the island of Manhattan and its environs, scraping the landscape clean.
in 1,000 years