For hundreds of years swimming in the Charles River was a popular summer activity . But in the 1950s, as public health concerns about polluted water became more well-known, swimming in the river was banned. Through the late 1990s, the Charles River was so polluted that rowers and sailors who fell into the water were advised to get a tetanus shot. In 1995, the EPA rated the water quality of the river as a “D”, but thanks to the efforts of several groups and 
agencies—most notably the Charles River Watershed Association, the US Environmental Protection Agency, and the Massachusetts Water Resources Authority—the Charles River now consistently receives a “B+” each year. Since 2005, the Charles has met state swimming standards for E. Coli in the area of the river below the Massachusetts Avenue Bridge most days of the year (the primary exceptions being after large rainstorms).
For more background on the history of swimming in the Charles and the efforts to cleanup the river and return swimming, see A Swimmable Charles?
To get involved or for more information about the Swimmable Charles Initiative, please email Swimmable Charles Coordinator, Karen Patterson Greene at kpg@thecharles.org.
Sponsors of the Swimmable Charles Initiative
...and thank you also to the Cabot Family Charitable Foundation!
All projects are conducted in partnership with the Department of Conservation and Recreation and under the guidance of the local Conservation Commission.