At the height of World War II, the lagoon had three working ramps, a lighted seadrome and a series of giant repair and maintenance hangars for the Navy's PBY-5 seaplane squadrons nearby, according to an on-line report by M.L. Shettle Jr. of the California State Military Museum.
Alameda officials, in the late 1920s, built an air strip called Benton Field on reclaimed land at the north end of the island for two reasons -- for the immediate use of Pan American Airways and as an incentive to attract the Navy to the city.
Over the next few years, the city continued to expand the airport's area by filling land into the bay. In 1935, Pan American took over the yacht basin and inaugurated civilian flying boat service to Hawaii and Asia.
In 1938, Congress finally appropriated $10 million to develop a Naval Air Station at the site. A year later, initial construction for the base provided for two carrier air groups, five seaplane squadrons, two utility squadrons, and an assembly and repair department began. In July 1940, additional funds were appropriated to enlarge the station with two seaplane hangars and a carrier berthing pier, as well as other facilities.
Shettle said that dozens of various Navy seaplane patrol squadrons passed through Alameda during World War II. The facility also had the distinction of playing host to one of the largest aircraft ever built, a Martin PB2M-1R Mars -- a seaplane contemporary of Howard Hughes' Spruce Goose.