The Connecticut River is the largest river in New Englan, flowing south from the Connecticut Lakes in northern New Hampshire, along the border between New Hampshire and Vermont, through Western Massachusetts and central Connecticut into Long Island Sound at Old Saybrook, Connecticut. It has a total length of 407 miles (655 km), and a drainage basin extending over 11,250 square miles (29,100 km²). The mean freshwater discharge into Long Island Sound is 19,600 cubic feet (560 m³) per second. The river is tidal up to Windsor Locks, approximately 60 miles (97 km) from the mouth. The source of the Connecticut River is the Fourth Connecticut Lake in New Hampshire. Some tributaries include the Ashuelot, West, Miller's, Mill, Deerfield, White, and Chicopee rivers. (The Swift River, a tributary of the Chicopee, has been largely replaced by the Quabbin Reservoir which provides water to Boston.)