June 20, 2016

Building the "Secret Cities"

The Pre-Fab Architecture of the Manhattan Project

What are city planners to do when the population grows 7,400% in under three years? Build—and fast.

The leaders of the Manhattan Project—a confidential government program that led to the creation of the first atomic bomb—had to do just that. As the Axis powers of World War II loomed, the American government scrambled to beat them to the scientific breakthrough of nuclear power by creating research centers in “Secret Cities” around the country—in Los Alamos, New Mexico; Hanford, Washington; and Oak Ridge, Tennessee. In addition to the facilities needed for this herculean effort, homes, schools, and the infrastructure for modern cities would be needed for the hundreds of thousands of people involved.

In response to the sheer number of homes required to support the Manhattan Project, director Gen. Leslie Groves and head scientist J. Robert Oppenheimer chose to build their cities with pre-fabricated homes—often referred to as cemesto or alphabet houses. With the help of the architecture firm Skidmore, Owings & Merrill, and engineers Stone & Webster, a single house with cement and asbestos walls in varied layouts could be manufactured every thirty minutes—averaging around 17 houses per day.

There were more than 20 different layouts often identified by letters—hence the moniker "alphabet house"—for single-family homes. The smallest style was the “Type A” with just two bedrooms; “Type B” was larger and rectangular in shape; “Type C” looked like an “L” shape; and “Type D” became a precursor for the American ranch-style home.

Oppenheimer, hoping to utilize the homes as “a means of attracting and rewarding residents,” called for each unit to come equipped with wood floors, a porch, and even a fireplace (only an aesthetic feature given the Tennessee heat in Oak Ridge). This request proved impossible for a project of this scale, though builders did their best to incorporate these amenities where possible.

Blueprint of Prefab house

Blueprint of the "Type D" ranch-style house.

Prefab house blueprint

Blueprint of the "Type A" single-family house.

“[These places] came from the mold of utopian planned communities built from a box, built to a pattern, built to embody and promote some larger goal.”

Peter Bacon Hales, "Atomic Spaces: Living on the Manhattan Project"

If Oak Ridge was an example of a successful foray into city planning on the part of the U.S. Government, Los Alamos is often viewed as a failed attempt to accommodate too many people in too short a period of time.

Peter Bacon Hales writes, “Both the original plan and the organizational ethos behind it were overwhelmed from the first…by the frenetic expansion that characterized the site throughout the war. Other elements conspired with this relentless, explosive spread in scale and demands.”

Because of this, housing and accommodations in the Manhattan Project’s New Mexico location varied greatly. The government took structures like the Los Alamos Ranch School, once a school for boys, and created living quarters for some of the thousands of scientists, engineers, and support staff. Groves contracted the Sundt Construction Company to build apartments for incoming workers and their families. However, as demand increased, more contractors were brought on, further convoluting the city planning and housing standards.

National Treasures: Manhattan Project Historic Sites

Hanford Reactor

The Manhattan Project marked one of the most transformative events in world history: the development of the atomic bombs that ended World War II and set the stage for the Cold War.

By the end of 1945, the US Government would spend an estimated $1.88 million—around $25 million in 2016 dollars—on building the sites in Oak Ridge, Hanford, and Los Alamos. Today, portions of these sites are now open to the public as part of the Manhattan Project National Historical Park.

To learn more about the history of the Manhattan Project and the "Secret Cities," look for your Summer 2016 issue of Preservation magazine.

Katharine Keane headshot

Katharine Keane is a former editorial assistant at Preservation Magazine. She enjoys getting lost in new cities, reading the plaques at museums, and discovering the next great restaurant.

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