Walnut River, a stream of southeastern Kansas, has its source in two forks which rise in the northern part of Butler county. Cole and Durechon creeks unite at a point about a mile southwest of the village of Chelsea and form the Walnut river proper, which flows in a southwest direction past the city of Eldorado. From here the river flows southwest past the town of Augusta, again making a turn almost due south and emptying into the Arkansas river south of Arkansas City in Cowley county. The river has a number of small tributaries, the most prominent of which are the Whitewater on the west and the Little Walnut and Rock creeks on the east. The stream is approximately 70 miles in length.