In the past, herring were blocked by this dam, and couldn't get further upstream to spawn. Now they can bypass the dam using the new fish ladder that was built by the State of NJ. This is at Batsto, NJ.
Water flows from the lake into the former ice passage behind the power house whose foundation is seen on the far side of the ladder structure. The fish ladder makes several turns before exiting parallel to the river's flow. Internal wood baffles provide resting areas for fish that must work upstream against both gravity and the waters flow.
Follow this link to see about: River Herring