"Heavy rains routinely trigger big sewage overflows in Baltimore, but there is growing evidence that chronic leaks from the region's aging, cracked sewer lines are a bigger threat to public health."
"Though storm-fed spills can be dramatic, Baltimore's' streams and harbor are also fouled on sunny days as storm drains yield grayish discharges that look and smell like sewage. That is what they are. Even the nearly $2 billion overhaul under way on the 3,100 miles of sewer lines in the city and Baltimore County won't be enough to make those waters safe, experts and activists say.
Leaks allow raw sewage to seep into storm drain pipes, which funnel rain from streets, parking lots and buildings into nearby waterways. In some cases, the waste is being piped directly into storm drains through illegal connections. But mostly it dribbles from fissures and breaks in an underground network that includes century-old brickwork."