The Platte River originates near Spaulding, Iowa in the southwestern portion of the state, and enters Missouri near the town of Sheridan, Missouri (river mile 146). The Platte River flows through northwest Missouri, and drains into the Missouri River near Farley, Missouri (Missouri River mile 391). The 102 River is the largest tributary of the Platte River, while smaller tributaries include Honey Creek, Long Branch, Third Fork, Little Third Fork Platte River, Castile Creek, and Little Platte River (Figure 1). The Platte River has a peak elevation of 1,320 feet, mean sea level (M.S.L.), and elevation at the mouth is 760 feet M.S.L. Within the basin, there is a mean slope of 3.1 feet per mile (Committee on Public Works 1965).
The basin covers portions of 14 counties (Figure Lo01). These include Andrew, Buchanan, Clay, Clinton, DeKalb, Gentry, Nodaway, Platte, and Worth counties in Missouri and Adams, Ringgold, Taylor, and Union counties in Iowa. Portions of two large metropolitan areas (i.e., Kansas City and St. Joseph, Missouri) occur within the Platte River basin. The City of Maryville, Missouri is the only other large city in the basin (population 10,663 people, 1990 Census). The total basin population in 1990 was 91,491.