The Schuylkill River has always been a bit of a mess. We got a water system to protect against yellow fever in the 1790s (spoiler alert: that's not how yellow fever spreads), and it was generally considered fancy and modern, but didn't help with the disease issues. We kept dumping waste into the river through all this, and by the second half of the 1800s, we had a typhoid problem. The water was so nasty that there was a WWII-era cartoon of a man drinking out of a jungle swamp with the caption "That man's from Philadelphia. He can drink anything."