Neponset River and Dam Postcards Neponset River and Dam No. 1311 Postcard. Caption on front: Neponset River and Dam at Mattapan, Mass. Postally unused. On verso: Published by C.O. Tucker, Boston. Facebook Twitter Print Friendly Skills Dam, Dorchester, Neponset River Posted on December 1, 2022 ← Neponset Railroad Station William E. Russell School →