Mto Charles ni mto wa Marekani. The Esplanade Association Charles River Watershed Association Charles River Conservancy Department of Conservation and Recreation - Charles River Archived 20 Januari 2012 at the Wayback Machine. "Swimmable by 2005" EPA Effort Charles River Swimming Club Charles River Museum of Industry US Geological Survey data on flow in Charles River at Waltham with links to data for other measurement sites[dead link]