Nuclear Power at Fort Belvoir

The U.S. Army Corps of Engineers designated its first nuclear power reactor as SM-1, shorthand for Stationary Medium Power Reactor Prototype Number 1, a name based on the Army’s classification of its reactors by mobility and power output. Although the goal of the Army’s program was to use nuclear power at remote sites with harsh climates, the Corps built its first reactor at Fort Belvoir, Virginia, because of its proximity to the U.S. Army Engineer School and the Army’s Engineer Research and Development Laboratories with their cadre of nuclear and engineering experts.

Despite having no experience building nuclear reactors, the Army and its contractor completed SM-1 in only 18 months using standard Corps of Engineers contracting and management procedures. The plant achieved its first self-sustaining nuclear reaction on April 8, 1957, and began producing power soon thereafter.

The purpose of SM-1 was to demonstrate that a significant amount of power could be safely and efficiently generated and transmitted over a commercial network. The Army also used it to test and refine the pressurized water design, the materials used in the reactor and shielding, and the lifespan and maintenance needs of future reactors. The SM-1 plant also served as a nuclear operations training facility for the Army and other military branches. The knowledge gained about reactor design and containment, construction materials, safety and health, fuel consumption, and lifespan proved invaluable for both military and private nuclear power operations.

SM-1 trained hundreds of nuclear reactor personnel and provided power to Fort Belvoir for years. The program accomplished its mission, but by the 1970s the country’s economy and energy needs had changed greatly from the early 1950s, and SM-1 was cost inefficient. In 1973 the Army shut down the plant and removed the nuclear fuel, though the building remained a training facility through the end of that decade. The Army plans to begin decommissioning the facility by 2020.

Apr. 2017


Visit the other pages of the Army Nuclear Power Program Virtual Exhibit

SM-1 Booties

Exhibit Home

SM-1 Dedication

Origins of the ANPP

Sturgis Core

Nuclear Power Generation


MH-1A Sturgis


Experimental Reactors


Shutdown & Legacy