In 1990, New Jersey placed five retired subway cars in a reef about 70 feet underwater; a decade later, they still provided three-dimensional structure

Under the chilly waters of the Atlantic Ocean, about 70 feet below the surface off the Jersey Shore, lies a small fleet of retired transit equipment. On July 19, 1990, five “K-Car” subway cars, originally built for PATH (Port Authority Trans-Hudson), the rail system connecting New Jersey and New York City, were sunk off the coast of Sea Girt, New Jersey, as part of a man-made reef project.

According to the New Jersey Department of Environmental Protection, this 1990 deployment was the state’s first experiment with subway cars as reef material. It would be over a decade before New Jersey brought in cars from a different source: in 2003, the DEP announced it was acquiring 250 retired New York City Transit subway cars, a wholly separate fleet from the 1990 PATH/SEPTA cars, for placement at five reef sites across the state’s coastal counties.

A scrapyard with a current


Submerging subway cars is a simple concept. Most of the ocean floor along the US Atlantic coastline is flat and sandy, so fish will often be found in areas that offer them shelter, such as areas with more structure. Subway cars are perfect for creating structure in the ocean; they are essentially ready-made. Many states along the coast have used various items, from decommissioned warships to bridge rubble, to create these reefs.

Subway cars had one particular advantage: there were thousands of them being retired from service in the New York area, and transit agencies were eager to get rid of them for free. As Scientific American has reported, the Metropolitan Transportation Authority faced a mountain of retired railcars weighing tens of millions of pounds, making donation to reef programs a practical solution for everyone involved.

Why old subway cars make great roommates for fish

New Jersey’s artificial reef program has said subway cars can attract roughly 200 species of fish and invertebrates, turning a pile of scrap steel into an active marine habitat within weeks. A separate, larger-scale example comes from Delaware’s Redbird Reef, built using a later generation of New York subway cars (not the same cars or program as New Jersey’s). Researchers there found the reef attracted large numbers of cold-water corals, anemones, sea stars and bryozoans, along with a marked increase in hermit crabs and clams.The downside to convenience

Monitoring of subway-car reefs has also turned up complications. Cars tend to settle into the seabed over time; researchers have found they reach a rough equilibrium with the surrounding sediment after about six or seven years, and the surrounding sand can scour into moats during storms. Despite being intended to last decades, the cars can deteriorate faster than expected. The 1990 PATH/SEPTA deployment ran into its own controversy. Environmental groups raised concerns about potential contamination in later shipments of New York City subway cars, and in the early 2000s, New Jersey’s acting governor temporarily rejected an offer of 650 additional cars over asbestos concerns before the state tightened its screening standards and resumed the program.As for the original five cars at Sea Girt: a 2004 survey, 14 years after they were sunk, found them roughly 70% intact and fully colonized by reef life, according to the DEP’s reef coordinator. Dive records describe the cars as still being more than half intact nearly 20 years after deployment, though with significant deterioration from decades of saltwater and storm exposure. Artificial reefs, in other words, are not a set-it-and-forget-it solution. They require ongoing monitoring, and the structures themselves can erode, shift, or sink well before their expected lifespan is up.

The reality of waste in a throwaway society

This story is easy to frame as a tidy “trash to treasure” narrative, but reusing waste at this scale takes real science, long-term monitoring, and money. New Jersey’s 1990 Sea Girt deployment, five cars, one state, one small reef site, is a useful illustration of what it actually takes to turn industrial waste into marine habitat, long before the far larger New York City Transit reefing program that followed more than a decade later.