Structural Ice Control Alternatives for Middle Mississippi River

Abstract

The middle Mississippi River, which extends from the mouth of the Missouri River near St. Louis to the confluence with the Ohio River at Cairo, Ill., is a critical navigation route throughout the year. During cold periods, the ice accumulations and ice jams that form on this reach can delay or suspend winter navigation, incurring great costs to industry as well as cities and towns whose economies depend on river commerce. Much of this ice originates in the Missouri River. With the onset of warmer air temperatures, the rapid release of these ice accumulations can result in substantial damage to river structures such as dikes, revetments, and levees. This study analyzed historical data and used numerical hydraulic models to assess the possibility of structural solutions to these ice problems. The study identified reach locations where structural ice control might be possible. A simple computer model then simulated the upstream progression of ice covers on the middle Mississippi to assess the feasibility of various ice control alternatives. An ice retention structure located on the Missouri River near its mouth was found to be the most favorable of the structural ice control options considered.