Los Alamos - Site Selection

By October of 1942, it had become increasingly evident, from the progress of experimental developments supervised by the Manhattan Engineer District at its other installations, that the immediate establishment of an additional research site was necessary for solution of specific problems in production of a nuclear weapon. The purpose of this new installation was the development, final processing, assembly, and testing of the atomic bomb. The contemplated scope of this part of the Manhattan Project was great enough to justify a separate title; accordingly, it was named Project Y.

Because the new Project was to be the most secret of the entire Manhattan Engineer District program, isolation was perhaps the first requisite for the site. However, many other factors had to be considered:

The area had to be large enough to provide an adequate testing ground.
The climate had to be such that outdoor work could continue throughout the winter months.
Access by roads and railroads was necessary for moving in extraordinary amounts of personnel and material.
Sources of construction materials had to be near enough to keep costs reasonably under control.
The population within a 100-mile radius of the site had to be sparse, to maintain both safety and security.
Utility facilities, including power, water, and fuel supply had to be available or conveniently developable.
Housing facilities had to be present to quarter at least the first arriving personnel.
The ownership and estimated value of the land and speed of acquisition had to be considered.
Soil characteristics, timber density, and type of terrain also had to be carefully investigated as the basis for future construction.
The location had to be remote from all sea coasts, as the possibility of enemy attack still had to be considered.

The U.S. Engineer Office and Real Estate Sub-office in Albuquerque surveyed several areas in New Mexico for this site using these requirements as a baseline. Their reports show the emphasis placed upon all of these points.

Sites Considered:

Sites at Gallup, Las Vegas, La Ventana, Jemez Springs, and Otowi, New Mexico, were surveyed. After careful investigation, the first 3 locations were rejected as failing to satisfy the established requirements. Then more detailed reports were made for Jemez Springs and Otowi.

The Southwestern Division Real estate Branch made a preliminary report on the possibility of locating the site at Jemez Springs, in November of 1942. All pertinent factors, such as water supply, housing facilities, access by road and railroad, ownership, and estimated value were considered. A further report, by the U.S. Engineer Office in Albuquerque, NM, covered in more detail the buildings around Jemez Springs which could be utilized for housing, and considered the sources and costs of construction materials, climate, labor supply, recreational facilities, population within a 100-mile radius, fuel supply, medical facilities, and the steps necessary to acquire the land for the proposed site. Had Jemez Springs been selected, 70% of the housing for the immediate needs of the Project would have to be built. This report included no recommendations, because the specific purpose of the site was unknown to the office making the survey.

In November 1942, the Manhattan District authorized the Albuquerque Engineer District to conduct a site investigation in the vicinity of the Los Alamos Ranch School in Otowi, New Mexico. Reports comparable to those submitted on the proposed Jemez Springs were prepared. The fact that the existing Los Alamos Ranch School buildings could be used for immediate housing was a primary factor in the recommendation of the site. Further, Otowi was more accessible, had a better water supply and lower valuation, and lay in amore sparsely populated area than Jemez Springs. All of these advantages plus the following favorable points could not be readily ignored.

Most of the area (some 47,000 acres of the estimated 54,000 required) could be obtained easily because it was already owned by the Federal government.
The private portion of the land was used mainly for grazing so the purchase price would be relatively small.
There was enough area available to ensure safe spacing of the various Project units.
The nearest town was 16 miles away, which tended to isolate the site.
The area was located on a mesa, making entrance to the site easy to control.
The main site area was relatively free from timber, and would necessitate little clearing.

Representatives from the Manhattan District, the Albuquerque District, and the Southwestern Division Real Estate Branch met in November 1942 at the Los Alamos Ranch School to consider that location in detail. The choice of the site was also discussed with Dr. J. Robert Oppenheimer, Project Director, and members of his staff, for further confirmation of its desirability. After careful consideration of all the cumulative reports and recommendations, Major General Leslie Groves determined that Project Y would be centered at the site of the Los Alamos Ranch School in Otowi, New Mexico.

After the final selection had been made, Lt. Col. J. M. Harman was designated as the Commanding Officer. The University of Southern California was also selected as the Operating Contractor to oversee the technical work.

Manhattan Project Heritage Preservation Association

Manhattan Engineering District

Project Y