The hidden health dangers of buried urban rivers
Explore any city enough, and at some point you’re likely to walk on water, so to speak.
Early city planners may have hoped for healthier cities when they covered up these streams, but it turns out they created new problems. Paving over and piping waterways often worsens flooding. And as new research by scientists at the Environmental Protection Agency indicates, buried streams can also exacerbate pollution.
More details here.