On the west side of the Mississippi, some seventy-five river miles north of Vicksburg, lay Lake Providence, a crescent-shaped body of water that could link the Mississippi via Louisiana bayous and rivers to the mouth of the Red River, miles south of Vicksburg. If successful, Grant’s army and Porter’s navy could get safely past Vicksburg and increase options for approaching the hill city out of the range of Pemberton’s guns. Grant’s engineers cut levees and created immense flooding, thus making it difficult to secure safe channels for the passage of Porter’s boats. The project dragged on, and Grant eventually gave up on it in favor of a new strategy to bypass Vicksburg.
In the back of his mind, he considered moving his army down the Louisiana side of the Mississippi and using Porter’s boats to ferry his men across to the Mississippi side, well below Vicksburg. And though it took him a while to embrace the idea as workable, the Lake Providence project produced a future benefit for the operation Grant had in mind. Massive flooding provided a water barrier that would protect Union troops marching south along the Mississippi’s west bank.
Before any of that happened, Grant tried other ideas. An ambitious Federal project took place well north of Vicksburg. Just south of Helena, Arkansas, on the Mississippi side of the river, flowed a waterway called Yazoo Pass. The pass emptied into the Coldwater, which flowed into the Tallahatchie. The Tallahatchie flowed through the Mississippi Delta region to the town of Greenwood, where it joined with the Yalobusha to create the Yazoo. A successful ascent via this route by Union forces would outflank Pemberton’s position on the Snyder’s Bluff heights overlooking the Yazoo northeast of Vicksburg.
To access the pass, Union engineers had to blow up a levee that protected area farmland in the north Delta from Mississippi River floods. Once Federal vessels entered the pass, they could maneuver across wide Moon Lake and enter a small channel that led to the Coldwater. Confederate naval commanders understood the potential the pass offered for enemy penetration deep into the Delta, but not until the threat materialized did Rebel fatigue parties rush to fell trees to obstruct the channels.
Grant thought the Yazoo Pass gambit worth the effort, and he told his engineers to investigate. The engineers liked what they saw, and on February 3 loud explosions sent high waters from the Mississippi roaring into the pass. The waters washed out a wide gap, and pro-Union planter and future Mississippi governor James Lusk Alcorn informed Grant’s chief engineer that the navy should have few problems getting down to the Yazoo. Grant quickly put together an amphibious force to take advantage of a seemingly golden opportunity.
The water roaring down rivers that led south into the heart of prime Mississippi farmland caused much damage. Slaves had to build levees to keep the water away from animals and farmland vulnerable to erosion, but it was a losing battle. Farmers moved everything of value they could to high ground, while watching their homes flood and many animals drown. By the time the water receded, the landscape was littered with ruined homes, dead animals, and fences scattered everywhere or simply gone, and the Delta black gumbo mud seemed to cover everything. Illness struck many farm families trying to salvage their livelihood.
Union operations continued, and David Dixon Porter sent instructions to one of his commanders, Watson Smith, to command a squadron that included seven vessels: Rattler, Romeo, Forest Rose, Signal, Cricket, Linden, and the ironclad Chillicothe. Later the ironclad Baron de Kalb and the tinclad Marmora joined Smith’s fleet. The Cricket and the Linden did not arrive in time for the expedition. Accompanying the naval detachment would be 600 infantry Sherman assigned to the operation. Smith’s mission was to get to the Tallahatchie, then to the Yazoo, then to the Big Sunflower. Smith must damage all things beneficial to the Confederacy and get as much information as possible about Rebel ironclads on the Yazoo. The possibility of another Arkansas worried Porter.
Natural barriers of large tree limbs hung over waterways, and driftwood, plus obstructions caused by Confederate axes, also worked to hold up the Union flotilla. By February 21 the last obstructions between the Mississippi and the Coldwater had been removed. Grant watched and waited. He turned down a request from McClernand to take 21,000 men and make another incursion into Arkansas. Grant would not be deterred; he needed all the men at his disposal to clear the Mississippi. Grant built up the Yazoo expedition, which now included two divisions. The Union force also included thirty pieces of field artillery and nearly four regiments of cavalry. Other boats, including two rams, Dick Fulton and Lioness, joined Smith’s squadron. Numerous troop transports further clogged the waterways. Grant modified his plan to include an assault on Grenada via the Yalobusha. Afterward, the amphibious force would return to Greenwood and descend the Yazoo.
Delays in getting troops to the pass, keeping channels clear, and engine problems among the vessels held up the long column’s entrance into the Coldwater until February 28. The actual ascent down the Coldwater toward the Tallahatchie did not commence until March 3. The head of the column reached the latter on the evening of the 5th. Curious slaves lined the banks, and smoke from burning cotton filled the nostrils of Federal soldiers and seamen. Landing parties managed to retrieve much cotton before planters had time to set their bales ablaze. The bluecoats also scavenged planter property for food, throwing scares into white plantation mistresses. Federal officers issued death threats to those who attacked civilians and their property. The trip downriver proved to be a slow one, due mainly to the cautious naval commander Smith. Not until March 11 would the Union force be positioned to attack Confederates awaiting in a stronghold at Greenwood called Fort Pemberton.
Commander Isaac Brown, of the ill-fated Arkansas, had been keeping an eye on Union activity at Yazoo Pass and sent word to Pemberton about the blown levee. Pemberton got the message on February 9 and responded to Brown’s request for heavy artillery with the news that no such guns were available. Anyway, Pemberton did not think a Union threat from that area very feasible. He soon changed his mind when messages about enemy activity continued to pour into Jackson. The Yankees were trying to get to the Coldwater, and one look at a map told the rest. Grant was trying to outflank Pemberton’s line on the Yazoo. Brown rushed to get two steamboats, Mary Keene and Star of the West, ready for combat. Pemberton hurried infantry to Yazoo City, where William Loring arrived to take command of Confederate forces gathering at Fort Pemberton.