New Jersey's 2019 dam removal brings eels and shad back upstream, study finds

Columbia Dam in New Jersey was removed in 2019 to allow the natural migration of fish. Recent studies show encouraging signs of recovery in fish populations, including American eels and adult American shad. Researchers monitored the river for nine years to assess the ecological impact of the dam's removal. The dam's removal also resulted in measurable improvements in water quality, including changes in temperature and dissolved oxygen levels.