stream in northeastern Kansas, U.S. It is formed by the confluence of the Republican and Smoky Hill (Smoky Hill River) rivers at Junction City and is joined by the Big Blue River near Manhattan. Flowing east into the Missouri River at Kansas City for a distance of about 170 miles (275 km), the Kansas drains an area of 61,300 square miles (158,770 square km), including northern Kansas and parts of southern Nebraska and eastern Colorado. Periodic floods (particularly in 1951, 1977, and 1993) have caused considerable damage to buildings and farms along the river's course, especially in the heavily developed Kansas City area.