Mar. 23, 2016

Vernon Smith/NOAA,​ 240-533-0662, 240-­638-­6447 (cell)
Christopher Johnson/U.S. Navy, 2​02-­685­-0766, 757­-593­-3891 (cell)

NOAA solves disappearance mystery of USS Conestoga

Ninety-five years ago, the World War I era Navy tug vanished with 56 crewmembers aboard

Today, NOAA and the U.S. Navy announced the discovery of the USS Conestoga (AT 54) in the Greater Farallones National Marine Sanctuary off San Francisco, 95 years after the Navy seagoing fleet tugboat disappeared with 56 officers and sailors aboard. The discovery solves one of the top maritime mysteries in U.S. Navy history.

photo of officers and crew shortly before they disappeared
The officers and crew of USS Conestoga, in San Diego, California in 1921. Lost for 95 years, the tug was discovered in the Greater Farallones National Marine Sanctuary off San Francisco. Credit: Naval Historical Center Photograph NH 71503

"After nearly a century of ambiguity and a profound sense of loss, the Conestoga's disappearance no longer is a mystery," said Manson Brown, assistant secretary of commerce for environmental observation and prediction and deputy NOAA administrator. "We hope that this discovery brings the families of its lost crew some measure of closure and we look forward to working with the Navy to protect this historic shipwreck and honor the crew who paid the ultimate price for their service to the country."

On March 25, 1921, Conestoga departed the Golden Gate en route to Tutuila, American Samoa via Pearl Harbor, Hawaii. When Conestoga failed to reach Hawaii by its anticipated arrival date the Navy mounted a massive air and sea search around the Hawaiian Islands, the tug's destination. Nearly two months later, on May 17, a merchant vessel found a battered lifeboat with the letter "C" on its bow off the Mexican coast leading to a search there.

For months, the ship's mysterious disappearance gripped newspapers across the country. Unable to locate the ship or wreckage, the Navy declared Conestoga and its crew lost on June 30, 1921. This was the last U.S. Navy ship to be lost without a trace in peacetime.

In 2009, the NOAA Office of Coast Survey, as part of a hydrographic survey near the Farallon Islands off San Francisco, documented a probable, uncharted shipwreck. In September 2014, NOAA launched a two year investigation codirected by James Delgado and Robert Schwemmer, West Coast regional maritime heritage coordinator for NOAA's Office of National Marine Sanctuaries, to document historic shipwrecks in the Greater Farallones sanctuary and nearby Golden Gate National Recreation Area. In October 2015, NOAA confirmed the identification and location of Conestoga during a mission that included an archaeologist from the Naval History and Heritage Command, as well as several senior Navy officers.

broadside photo of the uss conestoga
USS Conestoga at San Diego, California, January 1921. Credit: Naval Historical Center Photograph NH 71299

"Thanks to modern science and to cooperation between agencies, the fate of Conestoga is no longer a mystery," said Assistant Secretary of the Navy for Energy, Installations and Environment Dennis V. McGinn. "In remembering the loss of the Conestoga, we pay tribute to her crew and their families, and remember that, even in peacetime, the sea is an unforgiving environment."

Originally built to tow coal barges for the railroad, the Navy purchased Conestoga in 1917 for World War I service. The tug operated on the Atlantic coast and off the Azores, performing convoy and other duties before being assigned to harbor service in Norfolk, Virginia, in 1919. Ordered to duty in American Samoa, Conestoga steamed from Mare Island Naval Shipyard in California at 3:25 p.m. on March 25, 1921, headed for Pearl Harbor. After leaving the Golden Gate, the tug, possibly towing a barge, was never heard from again.

Weather logs indicate that around the time of Conestoga's departure, the wind in the Golden Gate area increased from 23 miles per hour to 40 miles per hour, and the seas were rough with high waves. A garbled radio transmission from Conestoga relayed later by another ship stated the tug was "battling a storm and that the barge she was towing had been torn adrift by heavy seas."

Based on the location and orientation of the wreck in 189-foot-deep water, three miles off Southeast Farallon Island, NOAA, and its technical and subject matter experts, believe Conestoga sank as officers and crew attempted to reach a protected cove on the island.

"This would have been a desperate act, as the approach is difficult and the area was the setting for five shipwrecks between 1858 and 1907," according to NOAA's report on the Conestoga discovery. "However, as Conestoga was in trouble and filling with water, it seemingly was the only choice to make." To see sonar images, historical photos and other materials, visit

Video, from cameras mounted on remotely operated vehicles used to explore the wreck site, shows the wreck lying on the seabed and largely intact. The wood deck and other upper features of the tug, however, have collapsed into the hull due to corrosion and age. Extensive marine growth, primarily white plume anemones, drapes the hull's exterior while various species of marine life. Wolf eels, ling cod and rockfish also inhabit the site.

During the remote dives, NOAA confirmed a number of features consistent with the description and plans of Conestoga published in 1904 including the size of the wreck; the fourbladed, 12foot 3inch diameter propeller; the steam engine and boilers; the number and location of portholes, mooring bitts, and ventilator locations; a large steam towing winch with twisted wire on the drum; two porcelain marine heads; and a single, 3-inch, 50-caliber gun that was mounted on the main deck in front of the pilot house.

No human remains were observed during the dives but Conestoga is protected under the National Marine Sanctuaries Act and the Sunken Military Craft Act of 2004, which prohibits unauthorized disturbance of sunken military vessels or planes owned by the U.S. government, as well as foreign sunken military craft that lie within U.S. waters.

NOAA's Office of National Marine Sanctuaries serves as trustee for a network of underwater parks encompassing more than 170,000 square miles of marine and Great Lakes waters. Through active research, management, and public engagement, national marine sanctuaries sustain healthy environments that are the foundation for thriving communities and stable economies.

NOAA's mission is to understand and predict changes in the Earth's environment, from the depths of the ocean to the surface of the sun, and to conserve and manage our coastal and marine resources. Join us on Facebook, Twitter, Instagram and our other social media channels.