Subway cars, like all pieces of technological equipment, become obsolete at some point. But how do you dispose of something so big and heavy in an environmentally conscious way? It turns out that, since 2001, old subway cars have been dumped into East Coast waters to form artificial reefs. This is perhaps the most creative method of repurposing that we’ve come across thus far–and we’ve seen lots!

Artificial reefs, or underwater habitats formed around sunken manmade objects, are not a new idea by any means. People have known for a while now that any sunken object will be colonized by marine life, provided that it isn’t deadly to the organisms. The first planned artificial reefs were boats in the early nineteenth century. Throughout the twentieth century, objects like school buses, refrigerators, and toilets have all transformed into reefs. Most recently, check out The Atlantic’s awesome photo collection of tanks, vessels, and NYC subway cars being sunk to form reefs.

In 2000, NYC Transit decided to phase out the entire Redbird line of subway cars. Previously, when individual or small groups of cars were retired, they would be dismantled and their parts would be sold off. This wasn’t possible with so many cars at once, and so, artificial reefs began to emerge in the waters of Delaware, New Jersey, Virginia, Georgia, South Carolina, and Maryland. New York cleaned the cars, and then gave them to the other states for free. After years on the sea floor, the cars would rust and degrade, eventually becoming part of the sea floor. According to the MTA website, by the time the project ended in 2010, approximately 2,580 cars had been converted into homes for creatures of the ocean.

In addition to creating new underwater habitats, the reefs have also increased fishing in certain areas. In 2008, Delaware’s reef had over 10,000 angler visits annually, an exponential increase from fewer than 300 in 1997. On the other hand, certain environmental advocates have been wary of the disposal procedure. Many cite the Redbird cars’ containing of asbestos as a serious concern to the health of the sea creatures. (However, more recently disposed cars that were not Redbirds were found to have no asbestos.) Others worry that creation of such reefs may actually lead to overfishing, as indicated by Delaware’s success.

Overall, the practice of creating artificial reefs from obsolete or broken human artifacts is here to stay–a rare solution that (mostly) appeases both transit officials and environmentalists. It is unclear whether any other subway disposal projects are planned or ongoing, but it is likely that more cars may be sunk in the future.

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