OTHER INFORMATION: Ways - T1710; Originally was a snag scow built by the Missouri River Commission. Remodeled into a snagboat in 1893 at Yankton, South Dakota. In 1899, the USE apparently assumed responsibility for the upper Missouri River and the Mandan and the James B. McPherson were transferred from MRC, based at Sioux Ice Harbor, South Dakota. Charlie Wonders built the Mandan's machinery which was considered unusual: compound engines with the high pressure engine inside the low pressure with three piston rods connecting to the crossheads. The Mandan frequently went to Fort Benton, Montana: 1908, 1912-1913, 1915-1918, 1921 and in 1922. She was the last steamboat to be seen at Fort Benton. In 1921, she was 50 miles up the Yellowstone River and was probably the last steamboat to go there