Construction Division Casey returned to
Washington, D.C. in October 1940 to become chief of the Design and Engineering Section in the Construction Division of the
Office of the Quartermaster General, under
Brigadier General Brehon B. Somervell. An enormous construction program was underway to meet the needs of
World War II. Working with a staff that included
George Bergstrom, a former president of the
American Institute of Architects, Casey set about revising the standard designs for barracks. A number of new features were added to improve comfort, safety, and durability. Substitutions were made for scarce materials. It was discovered that the standard 63-man barracks was now too small. Of the 81 companies in the new
triangular division, 51 fitted more easily into 74-man barracks. By slightly increasing the barracks size, substantial savings were made by reducing the overall number of buildings that needed to be constructed, the size of the
cantonment areas required, and the length of required roads and utility lines. Casey was promoted to
lieutenant colonel on 8 April 1941. The estimated cost was $35 million.
President Roosevelt subsequently moved the site of the building, over Somervell's objections, away from
Arlington National Cemetery.
Southwest Pacific In September 1941, General
Douglas MacArthur requested Casey's services as his chief engineer. Casey arrived in
Manila in October, shortly before the outbreak of war between the United States and
Japan. He acquired construction equipment from the National Power Corporation that was being used on the Caliraya project. Casey supervised demolitions as MacArthur's troops retreated to
Bataan, for which he was awarded the
Distinguished Service Cross. Unlike the rest of MacArthur's headquarters, Casey, who was promoted to
colonel on 19 December 1941 and
brigadier general on 25 January 1942, However, he joined MacArthur and sixteen other members of his staff in their
escape from Corregidor by PT boat in March 1942. For his service in the 1942 campaign in the Philippines, he was awarded the
Army Distinguished Service Medal. In
Australia, Casey became Chief Engineer at MacArthur's General Headquarters (GHQ),
Southwest Pacific Area (SWPA). He faced enormous engineering challenges. Most of
New Guinea consisted of mountains and jungle, with very few airstrips, ports or roads. All of these had to be developed to support operations. To provide additional expertise in construction, Casey had
Leif Sverdrup assigned to his staff as chief of the Construction Section, with the rank of colonel. As U.S. Army engineers were few, Casey worked closely with his
Australian Army counterpart at
General Sir
Thomas Blamey's Allied Land Forces headquarters,
Major General Clive Steele. Construction activities in Australia were also undertaken by civilians of the
Allied Works Council. Casey attempted to coordinate the activities of the various agencies. He had to fend off attempts by the
U.S. Army Air Forces to gain control of his aviation engineer battalions. The
Royal Australian Air Force organized its own airbase construction squadrons and only with difficulty was Casey able to control their activities. Casey's initial need was for engineer units to accomplish the daunting construction program, but soon stocks of engineer supplies and equipment began to run low. This was exacerbated by incoming units arriving without their equipment, or with it stowed on numerous ships, which often arrived at various ports in a theater where ports were hundred or thousands of miles apart. Critical shortages developed of
tractors,
graders,
concrete mixers and
welding equipment. In the absence of a proper stock control system, an overall coordinating agency, and adequate numbers of engineer depot units, the allocation and distribution of the meager supplies on hand were difficult tasks. The worst problem was spare parts. Equipment was operated around the clock under harsh conditions and soon wore out or broke. A large proportion of equipment became unserviceable for lack of spare parts. Requisitions sent to the United States took months to arrive, so recourse was made to the limited sources of supply in Australia. In September 1942, MacArthur decided to outflank Japanese troops on the
Kokoda Trail by sending an American
regimental combat team over the
Owen Stanley Range. Two alternate means of crossing the mountains seemed possible. One, the
Kapa Kapa Trail was known to climb to elevations above and present formidable obstacles. Casey and Sverdrup took charge of investigating the Abau Trail. They reached Abau on 18 September. Casey explored the harbor, taking depth soundings from a native canoe. Sverdrup set out for Jaure with a party of one American, two Australians from the
Australian New Guinea Administrative Unit, ten native police from the
Royal Papuan Constabulary and 26 native carriers. After eight days on the trail, scaling heights of , Sverdrup concluded that it would not be practical for troops to traverse the route and turned back. Meanwhile, Casey had concluded that the harbor was too shallow even for
lighters. However, the trip was not a total loss, for Sverdrup had sighted a plateau north of the Owen Stanley Range suitable for airstrips, allowing troops to be flown across the Owen Stanley Range. Casey was awarded the
Silver Star. For the
Battle of Leyte Casey's ASCOM had 43,000 men, of whom 21,000 were engineers. Casey and some members of his staff came ashore on A-Day; the advance echelon of his ASCOM headquarters arrived two days later. Work began immediately on the airfield at
Tacloban, and commenced on airfields in central Leyte soon after they were captured. Heavy seasonal rains thwarted attempts to develop the airbases in central Leyte and it was decided to abandon their development and construct a new airbase on the coast at a site occupied by Sixth Army headquarters. The need to get aircraft based on Leyte to stop the Japanese from reinforcing the island was so pressing that Lieutenant General
Walter Krueger agreed to move his headquarters. Casey had intended to come ashore on the first day of the
landing at Lingayen Gulf in January 1945 but was delayed a day because the destroyer he was traveling on had to escort a crippled transport. Despite enormous difficulties ASCOM was able to finish numerous projects on time and some ahead of schedule. On 13 February 1945, ASCOM was transferred to USASOS and redesignated the Luzon Base Section (LUBSEC). Casey then resumed his old post, now renamed Chief Engineer, US Army Forces Pacific. For his services as commander of ASCOM, he was awarded the
Legion of Merit. He was subsequently awarded a bronze
oak leaf cluster to his Distinguished Service Medal for his services as Chief Engineer, US Army Forces Pacific. He edited
Engineers of the Southwest Pacific, a seven-volume series about their wartime service. ==Later life==