BREMERTON — The Navy plans to take down the Puget Sound Naval Shipyard's historic hammerhead crane as part of a billion-dollar effort to turn antiquated facilities into a state-of-the-art dry dock for nuclear-powered submarines and aircraft carriers. 

The green steel of the crane has stood over the shipyard and surrounding city for nearly 90 years, becoming an iconic symbol of Bremerton. But the Navy says the crane, which is no longer in use, is due for costly maintenance and is vulnerable in earthquakes.

"The crane has also degraded after a quarter-century of non-use and it would be very costly for the Navy to maintain it in a safe condition," the Navy said in documents released Wednesday.

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The 25-story crane, built and installed in 1933 by many of the same workers who constructed the Empire State Building in New York, sits on a pier beside the shipyard's dry dock 3, the shipyard's closest dock to the Bremerton ferry terminal. Following a public process, the Navy will remove the crane from the National Historic Register so it can be demolished.  

The crane, one of the few still standing in the country, was embroidered on police patches, used in organization logos and emblems, and became an identifier for the surrounding city and an industrial workforce that helped win a world war.   

Bremerton Mayor Greg Wheeler, himself a retired Puget Sound Naval Shipyard worker, said the hammerhead has "been a symbol of industrial might and ingenuity." 

"Thousands of workers over generations brought the crane to life, and it has served as an important connection to our history and military heritage for the region’s residents and visitors," he said. 

The crane was officially retired in 1994 and is today just a relic, though it requires some maintenance and is still rotated about twice a year to ensure large vessels can get by it. 

The Navy invested more than $4 million in 1996 to repaint the crane. Millions more would be needed now to ensure its stability, the Navy said. 

The crane was originally built for about $500,000 under a New Deal program called the National Industrial Recovery Act. The Dravo Company of Pennsylvania, fresh off the Empire State Building project, constructed the massive structure before floating it through the Panama Canal and bringing it to Bremerton. Its steel includes weld identifier marks that indicate it came from Andrew Carnegie's steel companies, according to Kitsap Sun archives.

Though historic, Wheeler acknowledged the needs of the Navy in modernizing its infrastructure for a 21st-century world. 

"The new dry dock will ensure America’s fleet remains ready to protect our national security and preserve our quality of life for decades to come," he said.

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The Navy is investing billions of dollars into the Puget Sound Naval Shipyard, the largest of its four public shipyards with a workforce of 15,000. The crane's removal is part of that effort. 

The Navy plans to construct a new dock at the shipyard for the first time since 1961 to accommodate the Navy's newest nuclear-powered vessels. The Navy said Wednesday it will either be designed for dry dock 3, the shipyard dock closest to the Bremerton ferry terminal, or at Mooring Alpha, a location that would place it at the west end of the shipyard and next to dry dock 6, the existing dry dock for aircraft carriers. 

The 1919-built dry dock 3, located next to the Bremerton ferry terminal, has limited use that is dwindling toward obsolescence. The fleet of last-generation fast attack submarines, known as the Los Angeles class, will be dismantled entirely in the next decade. 

But that's not the end of its limitations. It can't handle nuclear fuel, at a shipyard where almost all vessels that enter its six dry docks are nuclear-powered.

The dock itself is too shallow; the shipyard must remove weight from subs, wait for the highest tides and over-flood the dock for boats to enter, according to a recent GAO report. 

Meanwhile, Mooring Alpha presents its own challenges. A mooring would need to be demolished, new wharf constructed, and along with dredging, a new turning basin would be required, the Navy said.

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The Navy says the new multi-mission dry dock will be able to maintain three new classes of nuclear-powered ships in one place: 

Building the new dry dock would give the Navy a second-such berth at the shipyard for aircraft carriers, and just the third it has among its public shipyards. That would take pressure off of dry dock 6, the other carrier dry dock, which is in need of hundreds of millions in repairs, including work tackling its seismic vulnerabilities.  

A public meeting will be held at 5:30 p.m. June 23 to get public feedback on the Navy's plans.