Just a few days after an abandoned dam was dismantled near Albany in New York, swarms of herring swam and spawned into the waters of a Hudson River tributary for the first time in nearly nine decades.
The industrial dam located on the Wynants Kill was removed in the hopes of saving the spawning habitat of herring and other ocean-going species. All of these species have suffered from habitat loss, overfishing and pollution.
The removal of the rusted steel dam is only the first of many barriers expected to be dismantled in the Hudson tributaries and other parts of the country. According to the advocacy group American Rivers, the Wynants Kill project is part of a larger movement that has already taken away nearly 250 dams across the United States since 2012.
The Hudson Estuary
Frances Dunwell, coordinator of the state's Hudson River Estuary Program, says most of the 1,500 dams in the estuary watershed are no longer in use.
"One of the key items on our to-do list by 2020 is to remove as many of these barriers as possible," says Dunwell.
Extending 150 miles north from the Atlantic Ocean, the Hudson estuary is a vital breeding ground for herring species such as the alewife and the American shad. The streams used to flash silver with herring during spawning runs in Colonial times.
However, the dams built during the Industrial Revolution caused populations of herring to move along the Atlantic Coast from South Carolina to Maine. Overfishing and pollution in recent years worsened the situation.
Three years ago, the Atlantic States Marine Fisheries Commission required 15 states to submit plans for restoring the spawning and nursery habitat in the estuary. At that time, climate change and dams were cited as the biggest threats.
Biology Professor John Waldman of Queens College says dams are artifacts of the Industrial Revolution and are persistent in causing harm.
He says experts should decide which dams are still useful and which should be dismantled.
Meanwhile, Dunwell says at least six privately owned unused dams are targets for removal. Furthermore, NY's Department of Environmental Conservation will offer private owners grants and technical support for the restoration project.
Precedents
On Maine's Penobscot River, a hydropower dam was recently dismantled to restore a major river. The removal of two dams plus the construction of a fish bypass opened at least 1,000 miles (1,609 km) of habitat for 11 species of sea-run fish.
Most projects center on removing small dams that have outlived their original purposes. Last spring, American shad swam up in Delaware's White Clay Creek for the first time. In 1777, a mill owner had built a timber-and-stone dam that obstructed the fish. It was removed in 2014 with the help of $200,000 federal and conservation group funding.
Photo: Jacob Bøtter | Flickr
