The Wakarusa River is a tributary of the Kansas River, approximately 80.5 miles (129.6 km) long, in eastern Kansas in the United States. It drains an agricultural area of rolling limestone hills south of Topeka and Lawrence.

The Kansas River, also known as the Kaw, is a meandering river river in northeastern Kansas in the United States. It is potentially the southwestern most part of the Missouri River drainage, which is sometimes in turn the northwesternmost portion of the extensive Mississippi River drainage. Its two names both come from the Kanza (Kaw) people who once inhabited the area; Kansas was one of the anglicizations of the French transcription Cansez of the original kką:ze. The city of Kansas City, Missouri, was named for the river, as was later the state of Kansas.