Jackson Bar Training Structure Study

Abstract : Three proposed alternatives intended to reduce shoaling at Jackson Bar, Alabama were investigated. A two-dimensional (2-D) hydrodynamic and sediment model was used to simulate hydraulic conditions at Jackson Bar, located on the Black Warrior-Tombigbee Waterway (BWT) in the vicinity of Jackson, Alabama. Jackson Bar, a sand bar, is located on the left descending bank upstream of a railroad bridge. Located in a bend in the BWT at Jackson, AL the railroad bridge presents a navigation hazard. Annual dredging provides the clearance necessary for tows to properly align with the bridge pass. The hydrodynamic model was validated with gage data from the USGS 02470050 Tombigbee River at Steamplant near Leroy, Al gage (Leroy gage), a previously-constructed HEC-2 model, and a previously-constructed WES physical model from 1987. Three alternatives were modeled in an attempt to reduce shoaling / eliminate dredging at Jackson Bar by using one or more river training structures (bendway weirs, dikes, kickers). A three-fold screening approach was applied to determine the feasibility of each alternative. The selected alternative was a variation of Plan D that used a kicker and transverse dikes.