Education
United States Military Academy.
United States Military Academy.
Commissioned in the United States Army Corps of Engineers, he served with the Union Army in Arkansas in 1864-1865. Mackenzie spent six years commanding a company of engineer troops at Willets Point, New York, that experimented in the use of torpedoes in coastal defense. In 1879 he began a 16-year stint as Rock Island District Engineer.
He built 100 miles of wing dams on the upper Mississippi River and produced a 40-foot channel between Saint Paul and the mouth of the Missouri River.
Called to Washington in 1895, he became Assistant to the Chief of Engineers in charge of all matters relating to river and harbor improvements. In that capacity Mackenzie reported on the federal statutes relating to water power for the Inland Waterways Commission, which was established by President Theodore Roosevelt in 1907 and presented in its preliminary report transmitted to Congress on February 26, 1908.
Mackenzie retired May 25, 1908, as a major general, he was recalled to active duty in 1917 at age 73 as Northwest Division Engineer serving again in Rock Island, Illinois. General Mackenzie died March 21, 1921, in Washington, District of Columbia
He was the first senior member of the Board of Engineers for Rivers and Harbors, which reviewed improvements submitted by Corps of Engineer officers. He was a member of the general staff corps and War College Board when appointed Chief of Engineers on January 23, 1904.
