Destroying a Dam – and Restoring an Ecosystem

July marked the beginning of the long-anticipated deconstruction of New Jersey’s 109-year-old Columbia Lake Dam. Located upstream from the mouth of the Paulins Kill, a 40-mile tributary of the Delaware River, the dam has not been used for power generation since 2016. Once completed, the months long, roughly $8 million dam removal project will help restore the Paulins Kill to health.

“The water quality will be improved,” predicts Montclair State Earth and Environmental Studies Professor Joshua Galster, who is measuring the impact of the dam’s removal on the Paulins Kill ecosystem. “Fish passage and habitat will be improved. The dam is about a quarter mile upstream from where the Paulins Kill meets the Delaware, so we hope fish like shad will swim upstream once the dam is removed and the river is restored.”

“It is a special kind of satisfaction to know that after more than 100 years and $8 million, American shad will no longer bump their noses on the Columbia Dam when they return to spawn and that people will have a cleaner, healthier waterway for recreation,” says Barbara Brummer ’68, The Nature Conservancy’s New Jersey State Director and Montclair State College of Science and Mathematics Advisory Board Chair. “The Nature Conservancy is pleased to have been a leader of many partners – including Montclair State University – on this project to improve the water quality in the Paulins Kill and reopen a 10-mile stretch of river to kayakers, anglers and migratory fish.”

Galster welcomes the opportunity be part of the dam removal project that involves The Nature Conservancy, the New Jersey Department of Environmental Protection, the United States Fish and Wildlife Service and others. “I’m only one part of the story,” says Galster. Montclair State Sustainability Science major Carolina Lemanski is currently working with him on the project, which he hopes will extend through next year and engage additional student researchers.

Galster and Lemanski are mapping the depth of the Paulins Kill riverbed along six river cross sections located between the dam and the Delaware River. They will ultimately compare measurements taken before and after the removal of the dam to assess changes in river depth. “We’re looking to see if there is change – either erosion or deposition – during different stages of the dam removal process,” Galster explains.

“I expect the river will deepen due to increased sediment transport,” says Lemanski. “The biggest ecological benefit would be the restoration of habitat connectivity for migratory fish.”

“Montclair State strongly encourages experiential learning activities, such as the monitoring of the Columbia Lake Dam removal project, for its students,” says College of Science and Mathematics Dean Lora Billings. “As we provide a service to our New Jersey community, the project provides students like Carolina with practical experience that sharpens their skills as they prepare to join the STEM workforce.”

According to Billings, the researchers’ work could also have potentially far-reaching implications. “Their expert analysis may provide the scientific basis for decisions about future dam removals.”