GEOLOGY OF THE RED RIVER CAMPAIGN OF THE AMERICAN CIVIL WAR

The Red River Campaign (10 March to 22 May 1864) was the Union’s largest combined army and navy campaign west of the Mississippi River. The primary objectives of the campaign were the capture of Shreveport, LA, seize major stockpiles of cotton in the area, and planting the Union flag in Texas. However, like many other Civil War campaigns, geology played a pivotal role in deciding the outcome. Union army and naval commanders overlooked several unique geologic and hydrologic factors influencing the Red River system. These unique properties included the great Red River Raft (a massive log jam that impeded navigation between Alexandria and Shreveport, LA), a series of rapids at Alexandria, LA, and the flashy nature and high sediment load of the river. The great Red River Raft in place for at least a millennium altered the flow regime of the River from a single channel to a series of anastomosing channels that created “strategic shooting lanes” for the Confederate defenders. The initial largely unsuccessful attempts at removing the raft were between 1833 -1838, so knowledge of the raft existed prior to the war. After removal efforts ended in 1838, the raft reformed quickly and was in place again by the time the Red River Campaign began. At the tactical level, the raft severely restricted the ability of the Union’s naval forces to maneuver and advance, thereby relegating the land forces to a largely defensive role. The rapids at Alexandria, LA, served as another navigational restriction that almost cost the Union navy it’s entire Red River fleet after it was trapped above the them during a sudden drop in the river level. The fleet was saved by one of the most imaginative engineering feats of military history; a “wing dam” proposed by Captain Joseph Bailey. These two dams constructed at the lower and upper rapids, raised the level of the Red River approximately 2.1 meters (seven feet) and provided sufficient draft that allowed most of the Union fleet to escape. Unable to achieve any of its objectives, the Campaign was considered a failure by the Lincoln administration and his military commanders. General William T. Sherman best described the failure of the Red River Campaign as “one damn blunder from beginning to end”.