Afterwards, he was for four years an Assistant Professor of Natural Philosophy and Engineering at the United States Naval Academy.
In 1868, he resigned his commission of First Assistant Engineer, with the rank of lieutenant, studied law, was admitted to the bar in 1869, and practiced for a short time in New York City.
In 1875, Van Buren was a member of the Tilden Commission to investigate the State canals.
He was State Engineer and Surveyor from 1876 to 1877, elected in November 1875 on the Democratic ticket.
Besides papers in theJournal of the Franklin Institute and the Transactions of the American Society of Civil Engineers, he has published Investigation of Formulas for Iron Parts of Steam Machinery (New York, 1869).