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The USS SAN DIEGO (armored Cruiser 6) Shipwreck  New York and New Jersey's Wreck Valley
Historical and current New York and New Jersey Shipwreck Information and images for scuba divers and fisherman.

USS SAN DIEGO SHIPWRECK                    USS San Diego 50 Cal Amo Shipwreck Video
By Capt. Daniel Berg 

USS San Diego Historical Photo commisioned as the CaliforniaOriginally launched as the California on April 28, 1904, by Union Iron Works in San Francisco, she was commissioned on August 1, 1907.  She was 503'11" long by 69'7" wide and had a displacement of 13,680 tons. She served as part of Theodore Roosevelt's Great White Fleet.  Her twin props pushed her at a top speed of 22 knots.  The warship's armament consisted of 18 three inch guns, 14 six inch guns both mounted in side turrets, four eight inch guns and two 18 inch torpedo tubes.  On September 1, 1914, she was renamed San Diego and served as the flag ship for our Pacific fleet.  On July 18, 1917, she was ordered to the Atlantic to escort convoys through the first dangerous leg of their journey to Europe.  The Diego held a perfect record, safely escorting all the ships she was assigned through the submarine infested North Atlantic without mishaps.

 On July 8, 1918, the San Diego left Portsmouth, New Hampshire, en route to New York. She had rounded Nantucket Light and was heading west. On July 19, 1918, she was zig-zagging as per war instructions on course to New York. Sea was smooth, the visibility 6 miles. At 11:23 AM, an ear shattering explosion tore a huge hole in her port side amidships. Captain Christy immediately sounded submarine defense quarters, which involves a general alarm and the closing of all water-tight doors. Soon after, two more explosions ripped through her hull. These secondary explosions were determined later to be caused by the rupturing of one of her boilers and ignition of her magazine. The ship immediately started to list to port. Officers and crew quickly went to their stations. Guns were fired from all sides of the war ship at anything that was taken for a possible periscope. Her port guns fired until they were awash. Her starboard guns fired until the list of the ship pointed them into the sky. Under the impression that a submarine was surely in the area, the men stayed at their posts until Captain Christy shouted the order  " All hands abandon ship ". In a last ditch effort to save his ship, Captain H. Christy had steamed toward Fire Island Beach, but never made it.  At 11:51 AM the Diego sank, only 28 minutes after the initial explosion. In accordance with navy tradition, Captain Christy was the last man to leave his ship. As the vessel was turning over, he made his way from the bridge down two ladders to the boat deck over the side to the armor belt, dropped four feet to the  bilge keel and finally jumped overboard from the docking keel which was then only eight feet from the water. As the Captain left his ship, men in the life boats cheered him and started to sing our National Anthem. Most survivors were picked up by nearby vessels, but at least four life boats full of men rowed ashore, three at Bellport and one near the Lone Hill Coast Guard Station. The San Diego was the only major warship lost by the United States in World War I.  

USS San diego's forward guns historical photo

 The original casualty reports ranged from 30 to 40. Apparently, the muster roll on the San Diego was not saved. The only list of men on board was the payroll of June 30, but since the end of June, they had received and transferred over 100 men. When the Navy eventually finalized the death toll, the official count was only six.  


 Since her sinking, there has been much debate about whether it was a torpedo, German mine or U.S. mine that sent the cruiser to Davy Jones Locker. Captain Christy wrote in his final log that they had been hit by a torpedo. The Navy, however, found and destroyed five or six German surface mines in the vicinity, so it is generally accepted that a mine laid by the U‑156 did the job. Ironically, the U-156 was sunk on its homeward journey possibly by a U.S. mine. 

On July 26, 1918, the U.S.S. Passaio arrived over the wreck. Two divers were sent down to report on the condition of the San Diego.  They reported the following; " Many loose rivets lying on the bottom.... Masts and smoke stack are lying on the bottom under and on starboard side of ship.... Ship lies heading about North depth of water over starboard bilge is 36 feet.... Air is still coming out of the ship from nearly bow to stern. It seems likely that as air escapes and she loses buoyancy, she may crush her superstructure and settle deeper". From this report the Navy concluded that the vessel was not salvageable. As quoted from their letter to the Chief of Naval Operations, " In view of the reported condition and position of the San Diego, the Bureau is of the opinion that an attempt to salvage the vessel as a whole, or to recover any of the guns, would not be warranted". They did, however, have concerns about the site being a hazard to navigation and the possibility of dynamiting her to increase the available depth of water over the wreck. On October 15, the U.S.S. Resolute took another sounding on the site. It found that the wreck had settled slightly and now had 40 feet of water over her, so the wreck was not blown up.


 In 1962, salvage rights to the San Diego were sold for $14,000.  The salvage company planned to blow up the wreck for scrap metal. Several groups including the American Littoral Society, Marine Angling Club and National Party Boat Owners Association banded together and lobbied. After a lot of  bad publicity, public outcry and a financial compensation, the salvage company agreed to give up the job.  The wreck, now an artificial reef, supports teeming amounts of aquatic life, not to mention many charter boat operations.

 Another interesting side step to the Diego story occurred when a Long Island diver attempted to raise the one remaining, 18 foot in diameter, 37,000 pound bronze prop.  He succeeded only in sinking his barge mounted crane which now rests on the bottom a short distance from the Diego's stern.  This barge has herself become a good lobstering dive. Someone else made off with the valued prop.


 On June 3, 1982, the N.Y. POST reported that the bomb squad had been tipped off that a local diver had recovered a two foot long, five inch diameter artillery shell from the San Diego. The diver had planned to sand blast it and stand it next to his fire place. The shell was confiscated, but because it was too powerful for Suffolk's detonation site it had to be transported to Ft. Dix, New Jersey and detonated by the Army. Lt. Thomas, commander of the Suffolk bomb squad, said, " it's the biggest warhead I've ever seen; it could go off just from drying out".

 On October 8, 1987, the research vessel Wahoo, captained by Steve Bielenda, ran a special trip to the San Diego. Aboard were some of the east coast's top wreck divers like Hank Keats, author of DIVE INTO HISTORY, Captain John Lachenmayer, Hank Garvin, Janet Bieser and myself. All participated in a dive to photograph, video and recover artifacts from a newly discovered storage room that George Quirk had located in the bow of this WW I cruiser. John Lachenmeyer entered the water and secured the anchor line to the wreck. He was soon followed by Hank and I who swam forward, then dropped down the starboard side to the location of a small corroded hole in the outer hull. We penetrated to the interior of the wreck. Hank reached a small room and took some photographs. As he backed off I proceeded to video an intact supply room, full of china dishes, bowls and silverware. This was to be the only view of the china room that day. Divers pulling artifacts from the silt covered floor reduced visibility to zero. As fresh teams of divers swam down to the wreck, lift bags popped to the surface carrying mesh bags filled with china, silverware and even lanterns. Many of the artifacts recovered on this very successful day were donated to local museums, used to decorate area dive shops or are incorporated into slide shows, TV shows and magazine articles, all aimed at increasing the public's interest in diving and shipwrecks.


 Today, the Diego lies upside down and relatively intact in 110 feet of water, 13.5 miles out of Fire Island Inlet.   One of the nicest aspects of this wreck is that it can be enjoyed at various depths. Divers can reach her hull in approximately 65 feet of water while her stern ammo room is in 90 feet and her stern wash out reaches a maximum depth of 116 feet of water. Besides supporting a huge array of fish life, she is one of Long Island's scuba diving hot spots.  Divers can find artifacts such as bullets, portholes, cage lamps, china and brass valves. The portholes found on this wreck are unique. They are made up of three parts, each of which is serial numbered: the backing plate, which is bolted into her armor plating, a swing plate window and a brass storm cover. What makes these portholes desirable to sport divers is the fact that the backing plates are almost impossible to unbolt while underwater. This means that while many divers have swing plates or storm covers, very few have a complete set and even fewer have a set with matching serial numbers.


 A few years ago, Steve Bielenda and I were diving on the Diego. I swam inside a gun turret where I caught a five pound lobster. When I turned around, I found a brass cage lamp and when I exited the wreck, there sitting half buried in the sand below me was an intact porthole. That was definitely one of my more productive dives. My next porthole from this wreck was not as easy and required approximately 15 working dives to recover. For the underwater photographer, this wreck provides structures, hallways and compartments which all make for beautiful photos.  

Please note that it is no longer legal to remove artifacts from this shipwreck. The Wreck has been place on the National Register and is now a protected site. The artifacts shown on this site were recovered prior to this new regulation.



This custom made ship in a bottle replica of the USS San Diego was created by Capt. Dan Berg in 2014. It depicts the Diego sinking after an explosion tore a huge hole in her port side.

In 2014 Capt. Berg created this replica Ship in Bottle model of the Word War I USS San Diego.


Book cover

Check out Gary Gentiles USS SAN DIEGO Book! (Click on cover for complete book listing)






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