 In 1897, President William McKinley appointed him to the Nicaraguan Canal Commission, which studied the possibility of a canal connecting the Atlantic and Pacific Oceans.A route through Panama was finally selected, and Haupt was appointed to the Panama Canal Commission.He was president of the Colombia-Canea Arbitration (1897), and was chief engineer of the survey for ship canals across New Jersey, and was consulting engineer on the construction of the Ohio-Lake Erie ship canal.