The Neponset River is a river in eastern Massachusetts in the United States. Its headwaters are at the Neponset Reservoir in Foxborough, near Gillette Stadium. From there, the Neponset meanders generally northeast for about 29 miles (47 km) to its mouth at Dorchester Bay between Quincy and the Dorchester section of Boston, near the painted gas tank.The Neponset River forms the southern boundary of the city of Boston, passing through the neighborhoods of Readville, Hyde Park, Mattapan and Dorchester, and forming with the northern border of the city of Quincy. In addition, the Neponset touches the towns of Foxborough, Walpole, ... Source: Wikipedia