SS United States is destined to become an artificial reef off Florida. Here's a look at that process.

It starts with towing the ocean liner from the Delaware River pier where it has been since 1996, and ends in the Gulf of Mexico with a half ton of C-4 explosives.

After departing Philadelphia, the SS United States will be towed to Norfolk, Virginia, to be prepped and then to Florida, where it will be sunk in the Gulf of Mexico to become an artificial reef. The ship has been docked in South Philly since 1996.
Joe Warner/USA TODAY NETWORK

The SS United States' next voyage will be its last. The historic ship that's been docked in South Philly for decades soon will head down to Florida — stopping in Norfolk, Virginia, for a quick cleaning along the way — where about 1,000 pounds of explosives will sink the ocean liner off the coast in the Gulf of Mexico.

The SS United States Conservancy, which owns the vessel, and Penn Warehousing, the landlord at the South Philly dock where the ship has been stored since 1996, reach a settlement regarding their rent dispute on Oct. 11, and the conservancy agreed to sell the ocean liner to Okaloosa County in Florida's panhandle.


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The new owner intends to turn the SS United States into an artificial reef. It's a delicate process that "really has to be done right," said Joe Farrell, the founder of Resolve Marine, in Ft. Lauderdale. His company sunk the USS Oriskany, an aircraft carrier used during the Korean and Vietnam wars that was decommissioned in 1976, which, for the moment, is the largest artificial reef in U.S. coastal waters. Since 2006 the USS Oriskany has been on gulf floor about 25 miles off the coast of Escambia County, which is located immediately west of Okaloosa County, the SS United States' new owner.

Okaloosa will spend $10.1 million to repurpose the SS United States, which still holds the transatlantic speed record that it set on its maiden voyage in 1952. The budget for the reefing project includes $1 million to open a museum with artifacts from the ocean liner.

County officials see this sum as a smart investment. Escambia County spent about the same amount 18 years ago to acquire, relocate and sink the the USS Oriskany, and officials there calculated that every dollar spent on that project returned about $150 from tourism related business, particularly scuba divers. It is estimated the SS United States would generate about $3 million a year.

There had been discussions that the SS United States would be towed from Pier 82 as soon as last Friday, but the ship's departure date was pushed back because the transportation logistics are still being finalized.

The challenges of moving this 53,000 ton, 72-year-old vessel that is 100 feet longer than the Titanic start in Philadelphia. When a ship has been docked for that long, it will get "tilted in," Farrell said, meaning the stern (the rear of the ship) isn't as deep as the bow (the ship's front). The vessel must be balanced in a way that brings down the bow and raises the stern. 

A clamshell dredge may be needed to move out some of the mud underneath. There also needs to be enough water in the channel to make it out of the Delaware River port.

Once the ship is out, the rudder will be locked and emergency pumps placed on board in case something goes awry on the way. Tugboats that can pull 150 tons will escort the SS United States it to Virginia, a journey that will take about a day, Farrell said. 

During its monthslong stay in Norfolk, experts will inspect the boat for asbestos and remove peeling paint that could harm marine life. The Florida Department of Environmental Protection makes sure the ship is environmentally safe to be sunk. Steel, wood and wiring will be removed, as well as anything that can be salvaged for the museum without compromising the ship's ability to travel to Florida. 

About two weeks after it departs Norfolk, the ship will arrive in Destin, Florida, for its descension to the depths of the Gulf of Mexico. 

First, the ship's seat valves, which allowed the boat to draw in water for its steam boilers, must be removed with explosives. Engineers must calculate the pressure resulting from the water that will flood the ship, and every void or trench in the ship needs to be prefilled with water to make sure the boat sinks properly. 

After the Coast Guard creates a security zone, crews will set off C-4 explosives that are strategically placed so the boat doesn't fracture. The explosives will tear open as many as 30 holes in the SS United States' hull, making sure it sinks quickly and doesn't tip over in the process. Farrell estimates between 800 to 1,000 pounds of explosives will be used, and it will take three to five hours to sink the ship to the bottom of the gulf. 

It's a complex process, Farrell said, because ships aren't made to sink, and SS United States, in particular, originally had been constructed to transport soldiers during wartime. The SS United States has two engine rooms in case one become incapacitated, and 20 watertight compartments to prevent it from sinking. The Titanic had 16, by comparison.

"It's a job that needs to be considered and handled by experienced people because this ... is the most unique vessel on the planet," Farrell said. 

Nick Tomacek, public information officer for Okaloosa County, said the county sought to acquire the ship as an eco-tourism attraction for scuba divers to explore the wreckage. It also is expected to be a destination for commercial and recreational fishermen. More than 560 artificial reefs have been added off the Destin-Fort Walton Beach area since 1976, and once the SS United States is sunk, it will overtake the Oriskany as the largest. 

"Here in this this area, in the Gulf of Mexico, we don't have any natural coral reefs that marine life really like and need," Tomacek said. "That's the idea behind artificial reefs, is to help the marine species here thrive." 

The SS United States was designed by William Francis Gibbs as a convertible troop carrier. Over the years, the ocean liner carried four presidents — Harry Truman, Dwight Eisenhower, John Kennedy and Bill Clinton —  and celebrities including Marlon Brando, Sean Connery, Walt Disney, Duke Ellington, Judy Garland, Marilyn Monroe, John Wayne and Bob Hope. 

"Having that land-based museum will help that legacy, that vessel live on," Tomacek said. "That ship is not a typical ship, it has a big story, so making sure that we keep that legacy alive and making sure that we tell that story as best we can in partnership with the conservancy is important to us."