Charles River

The Charles River is an 80-mile river in eastern Massachusetts. It flows northeast from its source at Echo Lake in Hopkinton to Boston Harbor, winding through 23 cities and towns and doubling back on itself several times. The river drains 308 square miles, but its source is only 26 miles from its mouth, and it drops just 350 feet from source to sea. The watershed holds more than 8,000 acres of protected wetlands, called Natural Valley Storage, that help prevent flooding downstream. A dam at the river's mouth, finished in 1910, stabilized the water level from Boston to Watertown and removed the mud flats there.

The Massachusetts Department of Conservation and Recreation (DCR) manages the Charles River Reservation and several launches along the river. There is a public trailer ramp on Nonantum Road in Brighton, next to Community Rowing. Waltham has an accessible launch on Woerd Avenue that can take trailers. Under state regulation, only car-top boats may be launched at several Upper Charles sites, including Elm Bank Reservation in Dover and Ames Street and Riverdale Park in Dedham. The Town of Millis lists carry-in sites at the Route 115 bridge and on Forest Road. In the Charles River Basin, boats may not go faster than 10 mph or make a wake within 50 yards of floats or non-motorized craft. The stretch between the North Beacon Street Bridge and the Boston University Bridge is a 5 mph controlled-wake area.

The lower river is busy with rowing, sailing and paddling, and it hosts the Head of the Charles Regatta. Swimming was opened to the public in 2013 for the first time in more than 50 years. Between Natick and Boston, a fish advisory says carp should not be eaten because of PCB and pesticide contamination.