At 1,450 miles, the Arkansas is the longest tributary in the Mississippi-Missouri system. From its source near Leadville, Colorado (Arkansas River Historical Society, 2003). Regulation of streamflow by storage and consumptive use in Colorado has reduced the river to a small stream where it crosses the border into Kansas. Across the plains of Kansas, the channel of the river is very shallow, with the banks being less than 5 feet above low water in some places (Blackmar, 1912). What the river channel lacks in depth it makes up for in width, being as much as 1-mile wide in some places.
As a result of land-surface characteristics and water use in Kansas, flows in the Arkansas River remain small for a considerable distance within the State, increasing gradually to Wichita where they increase due to inflows from the Little Arkansas River (Jordan, 1986). As it travels through Kansas, the Arkansas River flows through mostly agricultural areas and then exits into northeastern Oklahoma. There it is joined by the Canadian, Cimarron, Neosho-Grand, and Verdigris Rivers. It then crosses the State of Arkansas and empties into the Mississippi River 600 miles north of New Orleans (Arkansas River Historical Society, 2003).
The Arkansas River Basin in Kansas can be divided into two subunits--the upper Arkansas River Basin and the lower Arkansas River Basin (fig. 1). The Arkansas River Basin as a whole has a relatively low potential for runoff as soil permeability is generally high and precipitation is generally low (Juracek, 1999). This low potential for runoff along with relatively flat to gently rolling terrain throughout its basin results in generally localized flooding that is mostly confined to areas immediately affected by excessive rains.
|
|
| Figure 1. Location of Arkansas River Basin in Kansas and U.S. Geological Survey streamflow-gaging stations used to describe major floods in the basin. |