If you are interested in genealogical information about a person you believe worked on a Reclamation project, the materials available depend upon whether the person worked directly for Reclamation or worked for a contractor on the project.
If Reclamation directly employed the worker, there should be a personnel file available from the National Archives in St. Louis. There is a difference between the records of individuals who separated from service prior to 1951 and post-1951. The records of those who separated prior to 1951 are in the custody of the National Archives. The contents of the records (Official Personnel Folders) are releasable to the public for a fee.
For requests for records of former government employees who separated prior to 1951, one may send a written request to:
National Archives & Records Administration
ATTN: Archival Programs
P.O. Box 38757
St. Louis, MO 63138
For more information, you may visit http://www.archives.gov/st-louis/archival-programs/civilian-personnel-archival/
The records of employees who separated after 1951 are still in the custody of the creating government agency. Although the records are physically stored at the National Archives, requests for these records are "worked" by National Personnel Records Center employees (a part of NARA).
For requests for records of employees who separated after 1951, information is only releasable to the public under the Freedom of Information Act. Individuals may request information from their own file.
To learn more, please visit: http://www.archives.gov/st-louis/civilian-personnel/index.html.
Other possible sources of information regarding Reclamation employees are Reclamation’s “project history” for that year or official reports held in Reclamation records. A Reclamation “project history” was prepared annually for each Reclamation project beginning about 1910 and running fairly regularly into the 1960s and 1970s. Reports in Reclamation’s records could be in several locations: the National Archives in Denver, Colorado, has many of those records up into the 1970s and 1980s. Reports not yet in the National Archives might still be held in various field offices of Reclamation at the regional, area office, or project office levels. An accident in which a contractor employee died or suffered serious injury on a Reclamation project might also be reported in these sources.
If your person worked for a project contractor, which is a likely alternative, we are not aware of where contractor personnel records might be or whether they exist. However, Judith Sattler Irons has published a CD, “Hoover Dam Construction Worker Genealogical Database” containing “names of workers and their families who came to southern Nevada to build Hoover Dam, but [also including] sections on businesses and businessmen, contractors and subcontractors, government employees, and organizations involved with Hoover Dam construction”
Other than these resources, you might try the city directories for the location where your person worked. There are also often local newspapers, historical societies, museums, and colleges and universities with research collections that may give you valuable clues.