"For over a century, Mare Island was the Navy's Mare Island Naval Shipyard. The growing size and number of the country's naval fleet was making older facilities obsolete and led to increased building and refitting of shipyards nationally. In 1872 the US Public Works Department commenced construction of a 508-foot (155 m) drydock on the island, setting it on a foundation of cut granite blocks. The work was completed in 1891. A second drydock was begun in 1899, a concrete structure 740 feet (230 m) long set on wooden piles; it was completed in 1910. By 1941 a third drydock had been completed and drydock number four was under construction. The ammunition depot and submarine repair base were modern, fireproof buildings. A million dollar, three-way vehicle causeway to Vallejo replaced a ferry service.[1]
Before World War II, Mare Island had been in a continual state of upbuilding. By 1941, new projects included improvements to the central power plant, a new pattern storage building, a large foundry, machine shop, magazine building, paint shop, new administration building, and a huge storehouse. The yard was expected to be able to repair and paint six to eight large naval vessels at a time. Several finger piers had recently[when?] been built, as well as a new shipbuilding wharf, adding one 500-foot (150 m) and a 750-foot (230 m) berth. It employed 5593 workers at the beginning of 1939, and rapidly increased to 18,500 by May 1941, with a monthly payroll of $3,500,000. In 1941, the drafting department had expanded to three buildings accommodating over 400 naval architects, engineers and draftsmen. The hospital had 584 beds.[2]
In 1969 the Navy transferred its (Vietnam War) Brown Water Navy Riverine Training Forces from Coronado, California to Mare Island. Swift Boats (Patrol Craft Fast-PCF), and PBRs (Patrol Boat River) conducted boat operations throughout the currently named Napa-Sonoma Marshes State Wildlife Area, on the north and west portions of Mare Island. Mare Island Naval Base was deactivated during the 1995 cycle of US base closures, but the US Navy Reserves still have access to the water portions of the State Wildlife Area for any riverine warfare training being conducted from their new base in Sacramento, California.
During the latter years of Mare Island's military use, US Marines were trained for Security Management and Security Force Operations, including; F.A.S.T. (Fleet Anti-Terrorism Team), Security Guards, and Security Force Reaction Forces." (
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