The Platte River is a low-gradient, eighth-order river located in southwest Iowa and northwest Missouri. The Platte River originates in Union County, Iowa and flows southward for about 200 miles where it meets with the Missouri River near the town of Farley, Missouri. The watershed contains 2,419 square miles with 786 square miles (32.5%) in Iowa and 1,633 square miles (67.5%) in Missouri and lies within the Dissected Till Plains physiographic region. The average annual discharge for the Platte River at Sharps Station (98% of the drainage basin) is 1,925 cubic feet per second. There are 431 third order and larger streams within the basin, and major tributaries include the 102 River, Third Fork, Honey Creek, Castile Creek, and the Little Platte River. Streams within the basin are typical prairie type streams in that they are turbid and generally have homogeneous substrate consisting of silt and sand.
The basin is best characterized as rural with parts of the watershed lying within the cities of St. Joseph and Kansas City. Maryville is the largest urban area totally within the watershed, and it has a population of just over 10,000. Land use within the basin is dominated by agricultural practices and is comprised of about 60% row crop production, 17% pasture, and 11% forest. About 2% of the watershed is in public ownership. Channelization within the basin has resulted in about 250 miles of lost streams and a 19.4% reduction in total stream miles from fourth order and larger streams.
Major water quality concerns in the basin come from soil erosion from surrounding lands and unprotected stream banks and the deposition of this soil into basin streams. The high erosion and deposition rates within the basin have resulted in widening stream channels, as well as, filling of riffle and pool habitats. This, along with reduced water absorbing and holding capacity of surrounding lands, and the resulting exaggerated high and low flow conditions, have been the major limiting factors to the diversity and abundance of fish within the basin. Point-source pollution is not considered to be a major threat to basin streams relative to non-point sources. Notable point source concerns in the basin are those associated with municipal waste near the three major urban areas and pollution from Kansas City International Airport.
In the period from 1941 to the present, Missouri Department of Conservation personnel, personnel from the Iowa Department of Natural Resources, and angler creel records have documented 46 species of fish within the basin. Wide-ranging, tolerant species were the most common types sampled, with minnows (Cyprinidae) being the dominant family. Eleven rare or endangered species with aquatic associations inhabit, or at one time inhabited, the Platte River basin. Recreation use surveys indicated that fishing accounted for 51% of the total trips and 73% of the total hours of use on the lower Platte River over a one-year study period. Channel and flathead catfish represented 54% of the total harvest from the study. Other sport fish within the basin include largemouth bass, black and white crappie, bluegill, green sunfish, and walleye. Up to date angler surveys are lacking within the basin, but usage is probably high, especially with the basin’s location relative to major urban areas.
Main management objective
Private ownership accounts for 98% of basin lands. Therefore, the landowner is the critical link between improving streams within the basin or their further degradation. The main objective should be to increase public awareness, appreciation, and importance of stream resources within the basin. This would allow all of the goals set forth in this plan to be met.
- Improve water quality and improve and maintain water quantity
- Improve or maintain riparian and aquatic habitats
- Maintain diverse and abundant populations of native aquatic organisms while supporting the demands for quality fishing
- Increase public appreciation and awareness for stream resources
- Increase recreational use