Every spring, tens of thousands of river herring in Plymouth’s Town Brook have hit a roadblock less than half a mile upstream from the waters of Cape Cod Bay. These fish, in the midst of their annual migration from the ocean, were being slowed down by a narrow, 300-foot fish ladder through an unused dam — just one of seven man-made barriers that once blocked the river.
But this year, river herring and other migratory fish will be able to swim freely through all 1.7 miles of Town Brook again, for the first time in over 300 years.