Grant's Canal (also known as Williams's Canal) was an incomplete military effort to construct a canal through De Soto Point in Louisiana, across the Mississippi River from Vicksburg, Mississippi. During the American Civil War, the Union Navy attempted to capture the Confederate-held city of Vicksburg in 1862, but were unable to do so with army support. Union Brigadier-General Thomas Williams was sent to De Soto Point with 3,200 men to dig a canal capable of bypassing the strong defenses around Vicksburg. Despite being assisted by locally enslaved people, Williams was unable to finish constructing the canal due to disease and falling river levels, and the project was abandoned until January 1863, when Union Major-General Ulysses S. Grant took an interest in the project.
Grant attempted to resolve some of the issues inherent to the concept by moving the upstream entrance to a spot with a stronger current, but the heavy rains and flooding that broke a dam prevented the project from succeeding. Work was abandoned in March, and Grant eventually used other methods to capture Vicksburg, whose Confederate garrison surrendered on July 4, 1863. In 1876, the Mississippi River changed course to cut across De Soto Point, eventually isolating Vicksburg from the river, but the completion of the Yazoo Diversion Canal in 1903 restored Vicksburg's river access. Most of the canal site has since been destroyed by agriculture, but a small section survives. This section was donated by local landowners to the National Park Service and became part of Vicksburg National Military Park in 1990. A 1974 article in The Military Engineer speculated that the canal would likely have been successful if the dam at the downstream end of the canal had been opened.
History Background
During the opening days of the American Civil War in 1861, Winfield Scott, Commanding General of the United States Army, developed the Anaconda Plan for defeating the Confederate States of America. A major part of this plan was controlling the Mississippi River, to cut the Confederacy in two and provide a supply outlet for northern goods to reach foreign markets. In early 1862, the Union Army defeated Confederate forces in several significant battles, including Shiloh, First Corinth, Fort Donelson, and Island Number Ten. The city of New Orleans also fell to Union troops in late April. Between the capture of New Orleans and the battlefield victories, much of the Mississippi Valley was in Union hands. Flag Officer David Farragut commanded the Union Navy elements which had been present at New Orleans, and took his ships upriver to the city of Vicksburg, Mississippi, which was considered to be strategically valuable as it connected the regions west of the Mississippi River with the eastern portions of the Confederacy. The naval force was accompanied by 1,500 Union troops under the command of Brigadier-General Thomas Williams. After reaching Vicksburg in mid-May, Farragut unsuccessfully demanded that the city surrender to his fleet. On May 20, the first Union shot towards Vicksburg was fired by USS Oneida, and more bombardments followed on May 26 and 28 before Farragut decided to fall back to New Orleans, a move that was politically unpopular. The decision to withdraw was the result of falling river levels threatening to strand the Union ships, a shortage of coal, and Farragut being ill.
Another attempt on the city was made in June. Williams again accompanied the expedition, this time with a 3,200-man force. Williams's infantrymen, Farragut's fleet, and a group of ships armed with mortars commanded by Commodore David Dixon Porter left the city of Baton Rouge, Louisiana, on June 20. They reached Vicksburg five days later. On June 26, Porter and Farragut's ships attempted to bombard the Confederate artillery batteries defending the city, but were unable to do so. Confederate counter-battery fire was ineffective due to most Union ships anchoring out of range of the Confederate guns, and the remainder being anchored in a location shielded by heavy vegetation. Two days later, Farragut ordered most of his ships (but not Porter's) to pass in front of the city's defenses to meet a fleet of Union ironclads that had traveled down the river from Memphis, Tennessee. Farragut's movement involved navigating around De Soto Point, a peninsula of land on the Louisiana side of the river, where the Mississippi River made a horseshoe-shaped meander. The Union ships suffered damage, but were able to pass the batteries. Farragut and the commander of the ironclads, Flag Officer Charles Davis, agreed that the Union Navy could not capture the city without large numbers of army troops and that the needed number of infantrymen would not be released by the Union general-in-chief, Major-General Henry Halleck, for the Vicksburg operations.
1862 attempt
In 1853, as part of his survey of the Mississippi River for the Secretary of War, engineer Charles Ellet Jr. determined that the Mississippi was likely to cut across the narrow De Soto Point, leaving Vicksburg isolated on an oxbow lake. On June 6, 1862, the idea of cutting a canal across the point had been referenced in communication between Williams and Major-General Benjamin Butler. Williams selected a site for a canal to be built across the point in early June, and his men began digging on June 27, assisted by 1,200 local slaves, most of whom were from nearby plantations. These slaves had been impressed into service by Union raiding parties, although many had come willingly, having been told that they would be freed for their work. Williams intended to free them only if the canal was completed successfully and treated them harshly. As planned, the canal would have openings on the river upstream and downstream from Vicksburg. The canal's length was to be or with a width of and depth of . While the path of the canal could conceivably have been as short as , the longer route was chosen to stay further from Vicksburg's defenses.
If the plan worked as intended, the Mississippi would cut through the canal ditch, allowing Union ships to traverse the river without being fired on by the defenders of Vicksburg. It was also considered possible that the river would move from its old course through the canal cut, isolating Vicksburg from the river entirely. Progress was hampered by the falling level of the river and outbreaks of disease. Williams's soldiers were primarily men from New England who were unused to the climate of southern summers. The temperature in the area sometimes reached as high as , potable water was scarce, and the mosquito-ridden swamps in the area were havens for disease. Malaria, dysentery, and scurvy were common among the workers, and supplies of quinine to treat malaria ran out. Disease was further promoted by soldiers dumping raw sewage into the Mississippi River, which was also their source of drinking water.
The geology of the ground where the canal was dug was thought to consist of about of clay with sand below. A river current was expected to cut through the sand, but not the clay, so the clay needed to be entirely removed before the canal was opened to the river. The river was falling almost a day, although reports from upriver at St. Louis noted that the Mississippi was rising further north. This rise did not manifest itself downstream where the canal project was. A rise in the river's level was expected in June, but this never happened. By July 4, 1862, the cut was only about deep. A week later, the depth of the canal was below the surface level of the river. Williams considered opening the canal to the river at this time, but was delayed by soil collapses in the canal. By the time this was resolved, the river had fallen to below the trough of the canal. On July 17 the canal had a depth of and a width of . A steamboat was set up near the opening of the canal in a failed attempt to force water into the canal. The workers dug even deeper, but the walls of the canal collapsed in several places.
As the conditions deteriorated further, Williams decided that the canal was no longer feasible and ordered his men from De Soto Point, ending work on July 24. In addition to the problems at the canal site, the Confederates were showing signs of activity in the Baton Rouge area and near the Red River. His command had been reduced by disease to 700 or 800 healthy soldiers. The civilian workers suffered from sickness as well. With the withdrawal of the infantrymen being at least part of his decision, Davis withdrew his ironclads upriver to Helena, Arkansas. Farragut's ships also withdrew at this time, escorting the transports carrying Williams's infantrymen back to Baton Rouge. These deep-draft naval vessels moved downstream with difficulty. When the Confederate States Army later examined the area where the canal construction had taken place, they found 600 graves and 500 abandoned African Americans, most of whom were ill. The other African-American slaves had been either forcibly returned to their owners, or given three days's rations and instructions to walk back to their homes. The ditch had reached a depth of and was wide, but these dimensions were not enough to allow navigation because the river level had fallen below the ditch's trough. Although the proposed bypass of Vicksburg had failed, the diggers did destroy part of the Vicksburg, Shreveport and Texas Railroad, severing an important Confederate rail connection across the Mississippi.
1863 attempt
In late November 1862, Union Major General Ulysses S. Grant began an offensive aimed at Vicksburg. He took 40,000 soldiers into northern Mississippi while Major-General William T. Sherman made an amphibious thrust down the Mississippi towards Vicksburg. Both wings were forced to withdraw, Grant's after his supply line was wrecked by the Holly Springs Raid and West Tennessee Raids and Sherman's after a repulse at the Battle of Chickasaw Bayou. Sherman's men fell back to Milliken's Bend, Louisiana, Sherman being superseded in command by Major-General John McClernand. The two generals took the force north to Arkansas Post, Arkansas, and captured a Confederate fort in early January in the Battle of Arkansas Post. Grant then ordered Sherman to take a force down to the old canal site and resume work on the project. Overall command of the move against Vicksburg was taken over by Grant in late January 1863, although the lead elements of his force had already reached the area. A direct attack on Vicksburg was impractical; the strength of the Confederate defenses had been improved since Farragut's campaign the previous year, the terrain north of the city in the Mississippi Delta was impassable to an army, and a withdrawal to Memphis to make a second overland attempt would be publicly viewed as a defeat and would be politically disastrous.