the city allowed several large piers to be constructed within the bay, though only one was built. The pier, which was built in order to receive landfill for the other proposed piers, stretched northeast of Barren Island, south of Mill Island, and was wide. A total of six piers were planned for this area. In June of that year, a municipally owned pier was opened at Mill Basin. At the time, there were proposals to fill in between Mill and Barren Islands so 14 more piers could be built. By 1919, Atlantic, Gulf and Pacific was building three large dry docks on Mill Island. It was also constructing seven barges for the United States Navy. The fill for the docks came from as far away as Europe. As of that year, Mill Island was the site of at least six manufacturing and commercial concerns. One observer attributed the presence of several of these factories to the proposed improvements at Jamaica Bay. A contract for building concrete piers was awarded in 1921 and completed the next year. In 1925, the Flatbush Avenue extension to Rockaway Inlet opened, providing an additional of dock facilities and a strip of land for a road across the marshes. Construction of the docks started in 1927. During the late 1920s and 1930s, the New York City Department of Docks rented the docks to a number of small industrial firms. The development of the proposed docklands at Jamaica Bay spurred large increases in property values in Mill Basin, since the docklands was expected to gain a connection to the Long Island Rail Road. Planners wanted to create a spur of the Bay Ridge Branch south to Flatlands, with two branches to Canarsie and Mill Basin. A connection to Staten Island would be built via the planned Staten Island Tunnel, which would in turn allow freight to be delivered and shipped to the rest of the continental United States. The Port Authority of New York and New Jersey offered to build the new railroad link for $2 million and lease it to the city, but Mill Basin's further development was hindered when plans for rail service to the rest of Brooklyn went unrealized. Industrial activity continued through the 1960s. In 1927, United States Secretary of Commerce Herbert Hoover's "Fact-Finding Committee on Suitable Airport Facilities for the New York Metropolitan District" suggested Southeast Brooklyn as a possible site for