When the US Army arrived they found abandoned at
Darrit Island a 400-foot timber pier, a seaplane ramp, and warehouses, as well as a 5,800-foot runway at Dalop Island.
US Navy Seabees of the 100th Construction Battalion began improvement projects at the base. On
Delap the 5,800 feet (1,800 m) by 445 feet (136 m) runway was repaired and paved in
coral. The complete
Majuro Airfield became home to a number of units: two Marine dive-bomber squadrons, half a Marine patrol squadron, and staging a
United States Army Air Forces fighter group. The Navy used the Airfield for its
Naval Air Transport Service and patrols. The Majuro Atoll offered excellent fleet anchorage in the large protected
lagoon. The lagoon has depths of 150 to 210-feet, with only a few
coral heads. The lagoon islands had some sand beaches used for boats,
landing craft and
tank landing ships. On Calanin Island, at the entrance to the lagoon Seabees built a
signal station and a harbor entrance control station. Seabees built and manned at Acorn 8 Naval
dispensary. Seabees used both new construction
Quonset huts and captured buildings in their projects. Seabees built a 150-bed hospital. For the airfield, Seabees built a 12,000-barrel fuel depot for aviation gasoline storage on Bigariat Island and 4-inch pipe system to bring it to the airfield. For freshwater Seabees installed a water distillation plant. The 21 distillation stills turned seawater into 50,000 gallons of fresh water per day. The water was stored in a system of tanks and plumbing with a total of 180,000 gallons for all the islands in the base. Water tank trucks were used for long runs. The one captured pier was not able to keep up with the demands of the growing base, Seabees installed a deep-water 25 by 28 foot
pontoon floating pier. Seabees used coral to pave 10 miles of road and the top of 11,000 feet of causeways, making
Delap-Uliga-Djarrit. The causeways were built to connect the many small base islands together. A large Seabee camp, repair shops, and supply depot were built. For the troop
barracks,
mess halls, bomb-proof
shelters, and recreation facilities were constructed by the Seabees. Almost all of Dalop Island was taken up by the airfield, so the islets of
Uliga,
Laura,
Rairok, and others of the Majuro Atoll were used. In February 1944 the 100th Battalion was relieved with the arrival of Construction Battalion Detachment 1034. On 18 June 1944 the 60th Seabee Battalion was relieved with the arrival of Construction Battalion Maintenance Unit (CBMU) 591. Unlike most Pacific Navy bases, Naval Base Majuro was moved to a more forward location as the fighting moved towards Japan's homeland. On V-J Day,
surrender of Japan on 2 September 1945 the base was still in full operation. submarine tender ==Majuro Submarine Base==