A head shot would be nice.
The bull and gophersnakes (Pituophis catenifer) have strongly banded tails, the types of elaphe (rat snakes) in Kansas all have adark band between there eyes, and the prairie kingsnake looks like this.
Those are the other Kansas snkes that seem similar to me.
Hmmm, here is a question, does the belly look like this picture from animaldiversity.com? If so it is the Nerodia sipedon sipedon (Northern water snake)