The drainage system in southeastern Iowa is believed to be practically the same today that it was in pre-glacial times. By southeastern Iowa reference is made to the counties of Louisa, Des Moines, Lee, and the eastern part of Henry. Present evidence shows that every stream of any importance is now occupying a pre-glacial bed. This applies to the Mississippi River except possibly that part of the great river which lies between Montrose and Keokuk, where, for ten or twelve miles, it flows over a rock bed, making rapids so shallow as to necessitate a canal for the accommodation of river traffic during low water stage.
Proceedings of the Iowa Academy of Sciences
©1894 Iowa Academy of Science, Inc.
Fultz, Francis M.
"Coincidence of Present and Preglacial Drainage System in Extreme Southeastern Iowa,"
Proceedings of the Iowa Academy of Science, 2(1), 208-209.
Available at: https://scholarworks.uni.edu/pias/vol2/iss1/43