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.^[1] 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, Louisiana, 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.^[2] Flag Officer David Glasgow Farragut commanded the United States Navy elements that had been present at New Orleans, and took his ships upriver to the city of Vicksburg, Mississippi,^[3] which was considered to be strategically valuable as it connected the regions west of the Mississippi River with the eastern portions of the Confederacy.^[4] The naval force was accompanied by 1,500 Union infantrymen under the command of Brigadier General Thomas Williams.^[5] 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.^[3] 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.^[6]

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 navy, 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.^[7] 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 return 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.^[8] 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.^[9] Farragut and the commander of the ironclads, Flag Officer Charles Davis, agreed that the 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.^[10]

1862 attempt

Map of the Vicksburg vicinity and planned canal path, facing east

In 1853, 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.^[11] Williams selected a site for a canal to be built across the point in early June,^[12] and his men began digging on June 27, assisted by 1,200 local plantation slaves.^[13] These slaves had been impressed 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.^[14] As planned, the canal would have openings on the river 6 miles (10 km) upstream and 3.5 miles (6 km) downstream from Vicksburg.^[15] The canal's length was to be 1.25 miles (2 km)^[13] or 1.33 miles (2 km)^[12] with a width of 50 feet (20 m) and depth of 13 feet (4 m).^[13][15] While the path of the canal could conceivably have been as short as 0.75 miles (1 km), the longer route was chosen to stay further from Vicksburg's defenses.^[16]

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.^[15] Progress was hampered by the falling level of the river and outbreaks of disease.^[17] The temperature in the area sometimes reached as high as 110 °F (40 °C), 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.^[18]

The geology of the ground where the canal was dug was thought to consist of about 11 feet (3 m) of clay with sand below.^{[19][lower-alpha 1]} 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.^{[19][lower-alpha 2]} The river was falling almost 1 foot (0.3 m) 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.^[17] A rise in the river's level was expected in June, but this never happened.^[20] By July 4, 1862, the cut was only about 7 feet (2 m) deep.^[19] A week later, the depth of the canal was 1.5 feet (0.5 m) below the surface level of the river and on July 17 the canal had a depth of 13 feet (4 m) and a width of 18 feet (5 m), although the Mississippi River's level had fallen to below the trough of the canal.^[20] A steamboat was set up near the opening of the canal in a failed attempt to force water into the canal.^[21] The workers dug even deeper, but the walls of the canal collapsed in several places.^[13]

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.^[22][23] His command had been reduced to 700^[24] or 800 healthy soldiers by disease.^[23] The civilian workers suffered from sickness as well.^[24] With the withdrawal of the infantrymen being at least part of his decision, Davis withdrew his ironclads upriver to Helena, Arkansas.^[23] 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.^[25] When Confederate soldiers later examined the area where the canal construction had taken place, they found 600 graves and 500 abandoned African Americans,^[23] most of whom were ill. The other African-American workers had been either forcibly returned to their owners, or given three days's rations and instructions to walk back to their homes.^[26] The ditch had reached a depth of 13 feet (4 m) and was 18 feet (5 m) wide, but these dimensions were not enough to allow navigation^[22] because the river level had fallen below the ditch's trough.^[20] 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.^[27]

1863 attempt

Map of the Vicksburg defenses and De Soto Point. The lines represent the angles of fire of the Confederate batteries.

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.^[28] 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.^[29] 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.^[30] 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.^[31]

Despite some urging from a Vicksburg newspaper editor, Confederate troops had never filled in the traces of the canal. The steamboat Catahoula was sent to the area in January 1863 by the Union, under the command of a Lieutenant Wilson, to scout the remains of the canal cut. Both the captain of the vessel and a newspaperman on board reported that while there was water standing in the canal, it was stagnant and that the cut needed significant work before large ships such as the United States Navy ironclads could pass through it.^[32] Union Colonel Josiah W. Bissell, who had prior engineering experience, surveyed the canal on January 10 and noted that it was still in similar shape as to how Williams left it. All of the previously excavated dirt had been thrown to the side facing Vicksburg, which provided some protection from Confederate fire and made it easier to widen the canal, as the side to be widened did not contain excess debris.^[33] Although he was initially unconvinced by the project,^[34] Grant ordered that the digging resume after making some adjustments to the plans of the canal.^[35] Visiting Union officers later found that the water was only 2 feet (0.6 m) in the ditch and also noted the lack of a current,^[36] although depths of up to 8 feet (2 m) and widths up to 12 feet (4 m) were also reported.^[37] Tree stumps would need to be removed from the canal sides and a levee would need to be constructed to prevent canal water from flooding into where Union camps would be located.^[38]

A drawing of Grant's Canal being dug, published in Frank Leslie's Illustrated Newspaper (1863)

The project had the support of President Abraham Lincoln.^[39] The first workers were assigned to the canal project on January 23.^[40] The canal was widened to 16 feet (5 m) within a week, but because there was water in the canal, the newly widened points only had a depth down to the water level.^[37][40] The use of dredging boats would have been a solution to this problem, but none were available at the time.^[41] Water depth was increased to 5 feet (2 m), and in hopes of creating greater erosion in the canal, soldiers were ordered to dig pits along its sides.^[40] Another attempt to use a steamboat to push water into the canal was made, but again failed. By the end of the month, Grant was beginning to think that the canal project would not succeed, but continued with the construction.^[42] Captain Frederick E. Prime was placed in command of the effort on January 28.^[41] Outbreaks of disease struck again, and the levees around the project frequently broke, flooding parts of the canal. The diggers were also exposed to Confederate artillery fire. By now, the construction had been divided into 160-foot (50 m) sections, with the intention of making each section 6 feet (2 m) deep and 60 feet (20 m) wide.^[43] As these early attempts at working on the canal failed to achieve significant progress, Grant ordered that the upstream end of the canal be moved to a point 200 yards (200 m) upstream to allow for a stronger current to flow into the ditch.^[41][44]

Rains hampered the project by exposing poorly buried graves from the Battle of Chickasaw Bayou and turning the soil to a consistency Sherman described as "wet, almost water".^[35] Prime determined that the only way to deepen the canal would be to drain it, so he ordered any holes in the levees surrounding the canal plugged with dirt-filled gunny sacks. This process was completed by February 9, although it was noted that evidence of current-based erosion was finally sighted shortly before the canal was closed off. By February 12, the new entrance, which was constructed by 550 African Americans, had dimensions of 60 feet (20 m) across and 4 feet (1 m) deep. Water still kept rising through February 16, so one of the levees closing the canal off from the campsites was opened to drain the excess water into an unused area.^[45] On the 19th, a steam-powered sump pump was completed; the sump itself had been completed ten days earlier. That same day, 1,000 African American laborers were sent from Memphis to work on the project.^[46] In mid-February, the work assignments were rearranged so that each regiment had a 150-yard (100 m) section. The regiments were in turn subdivided so that an individual soldier only worked on the canal for two hours a day; units competed against each other in the construction work. Though many soldiers were theoretically available to work on the project, only 3,000 or 4,000 were assigned to it due to lack of tools.^[47][48] About 2,000 civilian laborers also worked on the canal during the life of the project.^[48] Two dredging boats were finally secured on February 16, the first arriving on March 1.^[49]

Union newspapers criticized the project, and the Confederates built new artillery emplacements capable of enfilading most of the canal.^[35] Optimism among those working on the canal grew as progress was made. Grant sent a message to Halleck on March 4 stating that the canal was only days from completion, and the second dredging boat arrived the next day.^[50] On March 7, the dam holding the upstream end of the canal failed, inundating the canal.^[37] The opening in the levee expanded until it was 150 feet (50 m) wide, and water flooded some of the Union campsites.^[50] This breach was a disaster for the project. Though the inflow of water had flooded the area, it had not produced any scouring effect.^[51] Prime ordered the lower end of the canal blown and attempted to plug the upper breach with a coal barge. It took days of frantic work to plug the hole.^[52] By March 12, the upper half of the canal only needed some widening and stump and tree removal, while the lower half required little widening but still some stump removal. Aside from those issues, the only remaining work to be done was filling a breach in one of the canal's side levees.^[53] The flooding had caused the cut to begin to fill with sediment, and the two dredging boats, Hercules and Sampson, were sent to try to clear the channel, but they came under Confederate artillery fire.^[22][37] With the soldiers flooded out and forced to higher ground elsewhere, the dredges continued the work.^[54] By March 19, Confederate fire had become accurate enough that the dredges could only operate under the cover of night.^[55] Grant wrote on March 22 that he doubted that the canal would be useful, and noted that Confederate artillery had been positioned to fire down the exit end of the canal.^[55] The dredges were withdrawn two days later.^[55] Their civilian operators had balked at working under enemy fire, stating that being shot at was not part of their contract.^[54] On March 27, Halleck was informed that the project had ended.^[54] Grant's canal had been a failure.^[56] The canal had reached a width of about 60 feet (20 m) and a depth of about 9 feet (3 m) to 12 feet (4 m).^[37] Grant viewed the canal construction as a good way to prevent idleness among his soldiers, but eventually conceived another way to get troops past Vicksburg.^[57] In Sherman's words, the canal was "labor lost".^[58]

Assessment

The historians William L. Shea and Terrence J. Winschel suggest that by the end of the project, Grant was only continuing the canal to please project supporter Lincoln and to distract the Confederates.^[48] At the time of the 1863 attempt, Grant was not particularly popular in the Union, and newspaperman Sylvanus Cadwallader wrote that he believed Grant could only keep his command by occupying his soldiers with activity. Some outside observers did view Grant's Canal as the best option for taking the city, and it received press attention in the Union, Confederacy, and Europe.^[68] Ed Bearss describes Grant's canal efforts as showing his willingness to try any available opportunity.^[69] Likewise, the historian Shelby Foote included the canal as one of seven different failed attempts made before Grant successfully took Vicksburg.^[70] A 1974 article published in The Military Engineer calculated that if the dam at the downstream end of the canal had been opened along with the breach in the upper canal, then a current strong enough to successfully erode through the canal cut would have probably been produced.^[37] Writer Kevin Dougherty believes that Grant's willingness to try various projects to get around the city had a side effect of confusing the Confederates.^[71] Engineer David F. Bastian suggests that the canal came close to success, and could have been successful if dredges had been obtained in January instead of March. He believes that using the dredges would have been more effective at widening and deepening the ditch than manual labor, and would have been less affected by rising river levels. The project would also have been completed quicker, allowing for time to reroute the downstream end of the canal away from the new Confederate batteries. If successful, the canal could have rendered Vicksburg moot by bypassing it. Historical consensus has nonetheless treated the project as impractical.^[66]