For the nation’s polluted rivers and streams, it has been a long road back — starting with the passage of the Clean Water Act in 1972. Waterways have made great progress since the days when boaters on the Charles River in Massachusetts were advised to go to the emergency room for typhoid and cholera shots if they fell in the water.

The Charles is much cleaner today. But another famous Boston River — the Mystic — still has a long way to go, reports the Boston Globe (“ A steady flow of troubles for the long-foul Mystic,” by Beth Daley). “Raw sewage still spews into the river during severe storms — including almost 4 million gallons in December,” the paper reports. Said one resident: “It’s an urban ditch.”

But communities are working on improvements, reports the Globe: “Court-ordered work to separate sewer pipes from storm drains is underway in Cambridge and Somerville, including a $116 million project for Alewife Brook, which flows into the Mystic.”

Said EkOngKar Singh Khalsa, executive director of the Mystic River Watershed Association: “People perceive this river as ruined, but it is a living system that is struggling to thrive.”