A graduate of the United States Military Academy at West Point, New York, with the class of 1909, Lee assisted with various domestic engineering navigation projects as well as in the Panama Canal Zone, Guam and the Philippines. During World War I, he served on the Western Front on the staff of the 82d and 89th Divisions and earned promotions to major, lieutenant colonel and colonel as well as the Silver Star Medal, the Army Distinguished Service Medal and the Croix de Guerre from the French government. After the war, Lee served again in the Philippines, then became District Engineer of the Vicksburg District, responsible for flood control and navigation for a section of the Mississippi River and its tributaries. During the Great Mississippi Flood of 1927, he directed relief work, attempted to shore up the levees, and coordinated the evacuations of towns and districts. He then directed various engineer districts around Washington, DC, and Philadelphia, Pennsylvania during the Great Depression.