On-Site Magazine

Old bridge gets new lease on life: Steel, concrete from dismantled span repurposed as artificial reef

By David Kennedy   

Bridges Construction Materials

HAMPTON BAYS, N.Y.—Thousands of tons of steel and concrete that stood proudly over the Hudson River for more than half a century have found a new purpose off the New York coastline.

Triangular trusses, concrete deck panels, steel beams and a long list of other components of the former Tappan Zee Bridge were laid to rest at the site of an artificial reef off Long Island this week.

Part of the state’s effort to bolster its marine life and recycle construction materials that have out-served their original purposes, 1,093 tons of material added to the Shinnecock Reef is the first of a dozen similar projects New York plans to undertake this summer.

“These artificial reefs are an investment in a stronger, more diverse marine ecosystem that will bolster the economy and bring a new purpose to the former Tappan Zee Bridge that will continue to serve New Yorkers for generations to come,” Governor Andrew Cuomo, said at a ceremony in Hampton Bays, N.Y. as barges laden with bridge parts dumped their loads about two miles off shore.


Along with components of the Tappan Zee Bridge, which was deconstructed last year after its replacement opened to traffic, the artificial reef fill consisted of other material from transportation projects across the state. A similar project has seen decommissioned New York City subway cars dropped into the Atlantic to create artificial homes for marine life.

The materials are cleaned of contaminants before being sunk and eventually come to rest on the sea floor. According to the governor’s office, large fish such as blackfish, cod and seabass are the first to take up residence. Barnacles, sponges, mussels, corals and other encrusting marine inhabitants then come to cling to the steel and concrete, eventually creating a sea floor habitat similar to a natural reef. New York got to work on its first artificial reef in the late 1940s.

The state says about 43,200 cubic yards of material from the Tappan Zee Bridge will find its way to offshore sites around Long Island throughout the summer.


Watch an excavator on a barge sink recycled bridge material off the New York coast:


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