He attended public schools in Appomattox and Richmond, Virginia, before receiving an undergraduate degree from Washington and Lee University.
During World War I, Flood served from March 29, 1918, until his discharge July 18, 1919, as a private in Company A, Three Hundred and Fifth Engineers, Eightieth Division.
Flood was not a candidate for election to the Seventy-third Congress, but returned to his legal practice and agricultural pursuits.
He was appointed assistant United States attorney for the Western District of Virginia and served from June 1, 1939, to January 28, 1940.
Joel Flood died in the Richmond Veterans Administration hospital Chesterfield, Virginia on April 27, 1964.