The Neponset River, a tributary to Boston Harbor, has been dammed in some fashion for the past 350 years (fig. 1). Historically, the river supported abundant populations of American shad (Alosa sapidissima), river herring (alewife, Alosa pseudoharengus), and blueback herring (Alosa aestivalis). While the Neponset River Estuary continues to support an important fishery of rainbow smelt (Osmerus mordax), two dams in the lower Neponset River block passage for shad and herring. Following a habitat survey in 1995, the Massachusetts Division of Fisheries and Wildlife of the Massachusetts Department of Fish and Game within the Riverways Program, began to stock both shad and herring upstream of the two dams in anticipation of fish passage (U.S. Army Corps of Engineers, written commun., 2002).