BOSTON (CBS) - It's 80 miles long and runs through 35 cities and towns: the Charles River is a natural resource that was once a real mess.
Though the worst of the pollution has been stopped, the improvement in water quality has leveled off. For the reason, you have to look to the skies and the ground.
The Charles is more alive than it's been for a long time. The birds, the fish and the people are back, but that's a relatively new development.
"It was really bad. It was basically an open sewer," said Kate Bowditch of the Charles River Watershed Association.
Most of those sewage overflows have been fixed and the river has gone from a nearly failing grade to a B+, according to the Environmental Protection Agency. The problem is, it's stuck there.
WBZ-TV's Todd Gutner reports.
"The biggest problem now is storm water pollution," says Bowditch.
Todd's Series: Exploring Our Nature
When it rains, storm water runs into the drains and some of it goes right into the Charles, carrying all the pollution from the streets.
"It ranges from road salt and sand, to litter and debris, cigarette butts and pet waste, and all of the oil and gas that might drip off cars and trucks," says Bowditch.
The runoff is often warm and can raise the water temperature causing toxic algae blooms and vegetation growth that can choke the river. However, at a renovation project at the old Waltham Watch Factory they're showing how developers can reduce the problem.
Todd spoke with Bob Zimmerman, the head of the Charles River Watershed Association:
"I don't think you can separate the river from the landscape," says Skip Burck, a landscape architect who designed a way to keep those 2 elements in harmony.
"What we've done is a series of infiltration trenches in the parking lot areas and courtyards, and to capture roof water, too, so that it goes first into the soil," says Burck.
That way, the water is filtered and cooled. Rain gardens absorb some of the run off while even more is directed from the down spouts into gravel holding areas.
Of course, the river is 80 miles long and this is just one project, so the Charles River Watershed Association is working with cities and towns the length of the river to decrease storm water runoff.
"It's a wonderful resource to our region for so many reasons. It's not just a matter of cleaning the river for fishes and frogs, it's really good for us, too," says Kate Bowditch.
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