New York tried to grow corals in old subway cars: how it was

After 58 years of service, the Metropolitan Transportation Authority (MTA) retired all remaining Brightliners (R-32 subway cars). Known for their shiny corrugated stainless steel panels, Brightliners said goodbye to New York earlier this month. They were sent by rail to be scrapped in Ohio, explains Fast Company.

Most wagons decommissioned over 10 years ago when over 1000 Brightliners were sent to coastal Delaware, New Jersey and Georgia. They were dropped to the bottom of the ocean as part of the artificial reef program. At the time, artificial reefs were developed to encourage recreational fishing. Fishing generated a whopping $2011 billion in federal and state taxes in 15. So the program made sense: the subway cars were welcomed by fishermen and divers. In addition, the MTA saved millions of dollars that it would have spent on train scrapping.

The Brightliners were planned to last more than 25 years underwater. But they began to fall apart just a few months after they were dropped. And that could be the end of the story. But climate change continues to deplete reefs and marine habitats across the country. Therefore, artificial reefs are becoming useful environmental tools. They have the potential to help restore lost habitat, improve the marine ecosystem and contribute to conservation efforts. But there are several criteria: the right size, the right material, and the placement in the right place.

У MTA there were good reasons to believe that the program would succeed. Just a few years before, they dumped more than 1000 Redbird wagons into the ocean, which remain at the bottom. ocean and to this day (partly because they contain carbon steel, which helps prevent corrosion).

On the subject: Hudson River is home to millions of oysters: why you can't eat them

In comparison, Brightliners are stainless steel. When the subway cars entered service in 1964, they were a mechanical and aesthetic innovation. Stainless steel made the wagons lighter on the tracks, but it worked against them underwater.

What environmental consultants say

Daniel Sheehy, environmental consultant, has been studying artificial reefs for over 50 years. He says the project failed for two reasons. First, because shells wagons spot welded. This led to the formation of a thin layer between the two metals and corrosion. Secondly, because the corrugated pattern made it easier for underwater waves to "capture" and further tear the stainless shell.

“It is important to learn from these mistakes and improve the process,” Sheehy said.

Artificial reefs date back to 1830th century Japan, where rubble and rocks were used to grow algae and increase game stock. In the US, such underwater projects are mainly built for recreational fishing. Here, the earliest recorded artificial reef dates from the XNUMXs in South Carolina.

In recent history, wrecks such as the famous SS Antilles in the Caribbean, are the most common forms of artificial reefs. But plenty of other reefs have been made from oil rigs, trams, and even underwater sculpture parks. For example, Reef Line in Miami, which is scheduled to open in the summer of 2022. The world's largest artificial reef is made from 3D printed ceramics in the Maldives.

Sheehy explains that several factors are necessary for the success of an artificial reef. Surface area is of key importance. It provides more space for encrusted corals and sponges that form a habitat for a variety of marine species. Weight is also important: the heavier the object, the less likely it is to be turned over by underwater waves and hurricanes. That's why tanks were so effective.

“The tanks were not meant to be taken apart,” he says. “They will last for 150 years.”

It is necessary not only to throw the wagons into the ocean

As far as materials go, anything from crushed concrete to damaged telephone poles can help, as long as you don't use tires. In the 1970s, for example, over 2 million car tires were tied together with steel clamps and dumped off the coast of Florida to expand the now infamous osborne reef. Except that the steel has rusted and millions of tires have been thrown into the ocean.

On the subject: Dine by the ocean in winter: charming cabins installed on the pier in New York

Even the best materials can be used incorrectly and in the wrong place. When a series of tanks were abandoned off the coast of Maryland, they sank right through the soft sediment. For comparison: World War II tanks at the bottom of the English Channel, where the bottom ocean more solid, did not budge.

In the end, it all comes down to the goal of creating artificial underwater rocky outcroppings of the seabed. When natural reefs are damaged, artificial reefs can help restore lost habitat. But artificial reefs can be used for conservation.

“If you build [artificial] reefs in the area and declare it a marine protected area, you will create additional habitat,” said Daniel Sheehy.

In his opinion, we need to think more about what we do in the ocean, because the built reefs are part of it. That is, something more is required than tipping a decommissioned train overboard.