Fort Union is located on the north bank of the Missouri River, as the Missouri River was the primary transportation corridor on the 1800's.
Because the Missouri River is controlled at Ft. Peck dam in Montana seasonal flows are regulated. Extreme flows are rare.
The park is actively restoring the native short grass prairie. SOIL-Soil surveys have been completed at the county level by the NRCS, but they are not available in digital format. ParkNet U.S. Department of the Interior FOIA Privacy Disclaimer FirstGov