GSA Connects 2022 meeting in Denver, Colorado

Paper No. 252-6
Presentation Time: 3:00 PM

AN INVESTIGATION OF THE GROWTH AND MOVEMENT PATTERNS OF MID-CHANNEL BARS IN THE MISSOURI RIVER


UNDERWOOD, Noah, Texas Christian University

Much is known about the formation factors of mid-channel bars, which involves accretion of unit bars, migration of bars within the channel, and docking mechanisms of these bars. However, little to no studies have been conducted which tracked comprehensive bar statistics over a significant period of time. Consequently, while much is known of the occurrence and geometry of various types of bars, little is known of their kinematics. Studies of the life-cycles of individual bars or small datasets of bars have been performed, but all of the bars in a given river have not been published. The Missouri River offers an opportunity to perform a similar study to the previously mentioned studies on a larger and more comprehensive scale.104 compound mid-channel bars were tracked between 1989 and 2018. Characteristics including life-cycle, surface area, docking patterns, and downstream migration were tracked and analyzed in order to create a comprehensive profile of the mid-channel bars in this stretch of the Missouri River. It was found that the average life-cycle of a compound mid-channel bar in this stretch of the Missouri River is 7.9 years. Additionally, bars tended to mostly form in wider areas of the channel and the post regulation Missouri has seen approximately 15% lower surface area on its mid-channel bars.