Born in Albany, New York he was educated at the University of Washington and MIT before attending West Point. He graduated in 1918 and was commissioned into the Army Corps of Engineers, completing his engineering studies at Camp Humphreys, 1918-21. He married Grace Hulbert Wilson in 1922.
After working throughout the United States he was attached to the Office of the Chief of Engineers and received a promotion to Captian in October 1934 and following courses at the General Staff College at Fort Leavenworth (1936) and the Army War College (1939) he was promoted to Major in 1940 and posted to the General Staff in Washington. He was deputy to the Chief of Construction and oversaw a number of projects including the construction of the Pentagon in 1940. In the same year he was promoted to Colonel.
In September 1942 he was made temporary Brigadier General and appointed as the military director of the nascent Manhattan Engineer District of the US Army Corps of Engineers, he provided the code-name 'Manhattan' himself from his Corps habit of naming districts after their headquarters' city. He had been seeking action overseas and was initially highly dubious of attaching himself to a little regarded weapons project. he was important in determining the sites to be used, finally deciding on Oak Ridge, Los Alamos and Hanford Engineering in Washington State. See Los Alamos National Laboratory for a detailed examination of the project.
Groves was promoted to temporary Major General in 1944.
He continued to play a role at Los Alamos as Chief of Army Special Weapons Project until January 1947 when the military relinquished control to the Atomic Energy Commission. Groves was made Lieutenant General in 1948, just before his retirement on February 29, 1948.
Groves went on to become a Vice-President at Sperry Rand.