The Story Of Oak Ridge, The Secret Town That Helped Build The Atomic Bomb

The Manhattan Project was an American program to develop nuclear weapons during WWII, hastily put together in 1942 after Nazi Germany developed nuclear fission. It was both a project of the highest national security as well as an enormous logistical undertaking. By the time the Manhattan Project concluded in 1947, it had employed 130,000 people and used more than 30 different sites (including Los Alamos, NM) in the US, Canada, and UK. 

The largest of these sites was Oak Ridge, TN. Built from scratch in the Manhattan Project's first year, it played an essential role in the development of the first atomic bombs in the US. But living in Oak Ridge was a surreal experience for its thousands of workers. Like many Americans in WWII, Oak Ridge residents had to uproot their lives and relocate to a town nicknamed "Secret City" and "the town behind the fence" for its extreme security measures. Despite these difficulties, Oak Ridge became a thriving community that continued to exist after the war.


  • Oak Ridge Was One Of The Largest Secret Sites Built To Carry Out The Manhattan Project

    Oak Ridge Was One Of The Largest Secret Sites Built To Carry Out The Manhattan Project
    Photo: Arthur S. Hardyman / Wikimedia Commons / Public Domain

    Oak Ridge, TN was the largest of all the Manhattan Project's sites, although it wasn't called "Oak Ridge" until the war had ended. Its first name was "Site X," and later Clinton Engineer Works, after the nearby town of Clinton.

    The main purpose of the Oak Ridge facilities was to enrich uranium for the construction of nuclear bombs. It was originally planned to house 13,000 workers but by the end of WWII was home to about 45,000 people. This made it the fifth-largest city in Tennessee at the time.

  • Almost 60,000 Acres Of Land Were Seized For The City, Uprooting Locals

    Almost 60,000 Acres Of Land Were Seized For The City, Uprooting Locals
    Photo: Manhattan Project / Wikimedia Commons / Public Domain

    To build the uranium-enrichment facilities at Oak Ridge, General Leslie Groves requisitioned an area of land about 59,000 acres along the Clinch River, 20 miles west of Knoxville, TN. He selected the site because it was relatively undeveloped and could also host thousands of people and their equipment. But it wasn't entirely uninhabited. Groves also authorized the removal of about 3,000 local families, including both farmers and Native Americans. Some had lived there for generations. 

    Many locals weren't sufficiently compensated for their displacement, and some received no compensation at all. The US government began posting removal notices in the fall of 1942, informing residents that they had just a few weeks to vacate. Many had to scramble to find alternate places to live and to coordinate moving all their possessions in a time when gasoline and auto tires were rationed for the war effort.

  • Most Of The Land Went To Plants That Processed Uranium And Plutonium

    Most Of The Land Went To Plants That Processed Uranium And Plutonium
    Photo: Ed Westcott / US Army / Manhattan Engineer District / Wikimedia Commons / Public Domain

    The Manhattan Project came about after Nazi Germany discovered uranium fission in 1939. Scrambling to build atomic-powered weapons that could compete with a hypothetical German bomb, the US government developed plans for both uranium- and plutonium-based weapons. Oak Ridge existed for two purposes: producing enriched uranium at a full-scale facility, and producing plutonium on a pilot scale. (The plutonium-based weapons were later developed at a facility in Hanford, WA). 

    Oak Ridge produced small amounts of plutonium for study at the University of Chicago, but its main production facility was the X-10 Graphite Reactor, which created the enriched uranium. The reactor was in operation from 1943 to 1963, and after WWII it had many purposes beyond building nuclear weapons: It produced the first electricity from nuclear energy, and also provided radioisotopes useful in fields like medicine, agriculture, and industry.

  • The Rest Housed The Plant Workers And Their Families

    To house thousands of workers and their families, the government brought in the architectural firm Skidmore, Owings and Merrill, which came up with the concept of "alphabet housing" - designing several home plans designated by letters of the alphabet. Generally, homes earlier in the alphabet housed fewer people compared with those later in the alphabet. 

    Alphabet houses were lightweight, prefabricated buildings that were constructed quickly. Many consisted of a material called "cemesto," a mixture of cement and asbestos. Overall, about 3,000 of these houses sprang up. 

    Meanwhile, Black workers weren't given alphabet homes, instead being forced to reside in "hutments," which were 14-by-14-foot single-room structures about the size of a storage shed that housed five to six people.

  • The Community Was Cut Off From The World With Fences, Guards, And Oaths Of Secrecy

    Because it was created to contribute to a top-secret military project, the community that eventually became Oak Ridge was shrouded in secrecy - like other Manhattan Project cites, it was called a "secret city." To protect its secrets, the city was surrounded by a fence with seven gates and multiple guard towers. 

    Workers were sworn to secrecy; they couldn't discuss their work with outsiders or even with their fellow Oak Ridge residents. As a result, may didn't know they were working on an atomic bomb until the war was over.

  • The Town Had Amenities Like Theaters, A Library, And Even A Symphony Orchestra

    As a fully functioning town largely cut off from the outside world, Oak Ridge also included amenities that eliminated the need for residents to leave. By the end of the war, the town was home to 165 retail shops, 10 schools, churches that catered to 17 denominations, a live theater, a library with 9,400 books, a community center, and a swimming pool. 

    Oak Ridge was even home to a symphony orchestra begun by Manhattan Project scientist and cellist Waldo Cohn, who organized a chamber music group so he could keep his skills sharp. It grew into the Oak Ridge Symphony, which is still in operation today. 

    Residents were still allowed to leave; they just weren't permitted to speak about it. Local Tenneseeans could identify Oak Ridge residents by their characteristic muddy shoes - because the city was constructed so quickly, most of it was often coated in a layer of mud. Residents from Knoxville and elsewhere could only enter Oak Ridge with a permit from a resident, and they weren't allowed to bring cameras.