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Historical Vignette 074 - Army Engineers Oversaw Military Reconstruction

Army Engineers Oversaw Military Reconstruction in Post-WWII Occupied Japan

Under the terms of surrender that ended World War II, Japan fell under Allied occupation. U.S. Army engineers faced a daunting challenge in constructing facilities for the occupation forces and rebuilding the vanquished nation’s infrastructure. The immediate postwar standard of living in Japan had sunk to subsistence levels and U.S. Army Air Force bombing raids destroyed much of the nation’s industrial base. Roadways originally were designed for light vehicle traffic and frequently were unsurfaced, and railroads often were of differing gauges. Unskilled labor was plentiful but craftsmen were scarce. Sewage systems were nonexistent. To complicate matters, at the occupation’s outset, Japanese construction firms were not considered financially sound nor did they operate with bonding or insurance. 

Under the Far East Command—the ruling authority in occupied Japan—the Supreme Commander for Allied Powers created an engineer district equivalent, the Army Construction Agency, Japan, to accomplish all project work, with project review performed by the Army Forces Pacific theater engineer. However, the engineering support for the occupation was the responsibility of engineers from the U.S. Eighth Army, the Sixth Army Engineers out of Kyushu, and elements of the 5th Air Force Engineers. Additionally, to overcome a shortage of engineer troops, indigenous labor gangs were organized.

Military vehicles roll down a street in Osaka, Japan, past the portable canvas tanks of a water purification station run by the 323d Engineers, 98th Division, 1945.   Quonset hut, originally barracks for the 736th Engineers, is set in place to be reused as office space by the 598th Engineer Base Depot, 1947.

The intact Japanese civil government bore the financial responsibility for infrastructure reconstruction, including military programs. American area commanders funded projects by levying requisitions known as procurement demands on local Japanese administrations. After some abuses arose, the commanders lost their ability to make such requisitions. Instead all requirements were processed through General Headquarters. Eventually, the Japanese government, using Termination of War funds, was able to procure its own construction contractors. All were Japanese companies either created or expanded in response to the building requirements.

The centerpiece of the U.S. reconstruction effort in Japan was the base-building program to construct facilities supporting the occupation forces that at the same time would have joint-use applications. While in the early part of the occupation the U.S. military engaged in or supervised the Japanese in humanitarian and related civilian activities, the bulk of the engineering projects it performed involved converting existing facilities for the Eighth Army and other military units. Housing, hospitals, airfields, and administrative and operational structures were provided for American garrison divisions by rehabilitating former Imperial Army military camps. Many Japanese housing units were converted to house Americans and their dependents.

Other than some prefabricated buildings and petroleum tanks, building materials came from the local economy. In all, 15,000 dependent housing units were built or converted. Furthermore, former Japanese military ports and industrial plants became not only U.S. Army depots and logistics staging areas but also dual-use facilities. Repair and utilities support to all installations was funneled through regional post engineers, under whom utilities detachments and technicians resided. Because of the lack of civilian-operated heavy earth-moving equipment, engineer units performed all earthworks. By 1950, Army engineers had carried out total construction valued at more than $400 million.

The 598th Engineers, Parts Supply Division, trying to bring order out of chaos as heavy shipments arrive from other commands to the Yokohama base depot, early 1948.   The 872d Airborne Engineers repair the runway on Atsugi Airdrome, Japan. The asphalt "kettle" was used to liquefy barrels of asphalt that was spread over areas under repair, 1945.


With the outbreak of the Korean War in June 1950, a new and extensive construction support program had a direct effect on Japan’s rehabilitation. Procurement totaled nearly $1 billion annually by 1953 and involved contracts with 3,000 Japanese firms. By the end of 1951 the Japanese were able to negotiate an end to Allied occupation.

The peace treaty that went into effect in 1952 allowed for a mutual defense pact under which U.S. forces remained in Japan. This agreement began the permanent base construction that has continued with the establishment of the Far East District in 1957 and the Japan Engineer District in 1972. The work of Army engineers, although begun in the wake of a war with such terrible devastation, in large measure contributed to the rise of a former enemy as both an advanced, democratic nation and a stable bulwark for American interests in the wider region. This effort lives on in the continued cooperation among uniformed and civilian employees of the U.S. Army Corps of Engineers, its contractors, other U.S. agencies abroad, local nationals, and the host government.


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September 2003