​Philly's Greened Acres Alleviate CSO Burden on Subterranean Streams

A significant problem for many municipalities is combined sewer overflows (CSOs). Now, imagine the scale of the problem when your streams are your sewers. That’s the problem the Philadelphia Water Department (PWD) is dealing with today, but first, how did they end up here? Long before the city was covered with streets, sidewalks and skyscrapers, it was nothing but rolling hills, farmland, forest and streams as far as the eye could see — a lot of streams. Like all developing cities, that land became less pristine as the population grew, and its creeks became the convenient receptacle for just about anything