GEOLOGY OF GRANT'S CANAL: THE UNION'S ATTEMPT TO BYPASS VICKSBURG, MISSISSIPPI
In January 1863, work on the canal was resumed by troops under the command of Major General Ulysses S. Grant and the project became known as Grant's Canal. Digging continued into spring, but a rise in the river on March 5th broke thru the cofferdam at the head of the canal and flooded the excavation. The canal immediately began to silt up despite the efforts of two steam-driven dipper dredges, put to work clearing the channel. The dredges, however, were exposed to confederate artillery fire from the bluffs at Vicksburg and driven away. By March 24th Grant had decided to make a bold change in tactics and work on the canal was abandoned.
The canal project failed because of a lack of understanding river geomorphology including proper canal configuration (elevation and shape) to effectively use the river's erosive power to deepen the excavation. Ironically, nature later accomplished what the Grant's troops could not when on April 26, 1876 the Mississippi flooded across Desoto Point (forming Centennial Cutoff) and isolated Vicksburg from the Mississippi River.