As Union soldiers labored on the canal across De Soto Point, opposite Vicksburg, Grant's engineers investigated alternate water routes to reach the city. One such route led through a 200-mile connecting chain of waterways from Lake Providence to the mouth of Red River, then up the Mississippi River for another 150 miles to Vicksburg. The route could also be used to send reinforcements to assist Maj. Gen. Nathaniel P. Banks in his operations against Port Hudson, LA.
The route was examined by Lt. Col. William L. Duff of Grant's staff, and declared practicable provided a short channel of five-foot depth was cut from the levee to Lake Providence. A working party from Col. George W. Deitzler's brigade began excavating the ditch in early February 1863. Once the ditch was completed, the levee would be blown permitting flood water from the Mississippi (then fifteen feet higher than the level of the lake) to rush in and provide water of sufficient depth for vessels to cross Lake Providence to Bayou Baxter, then into Bayou Macon, providing clear passage over other streams to the Red River.
In early March, Grant personally examined the route and reported that "there was scarcely a chance of this ever becoming a practicable route for moving troops through an enemy's country." Despite his outlook, work on the canal continued, and on March 17 the levee was cut. By March 23, the water levels of the Mississippi and Lake Providence were nearly equal, permitting vessels to be taken through. By the end of March, however, Grant had determined to move his army overland, proceeding south from Milliken's Bend, LA. The Lake Providence Expedition was abandoned.
Federal efforts at Lake Providence had the unforseen result of protecting the right flank of Grant's column as it marched south from Milliken's Bend due to the flooded interior waterways of Louisiana providing an extensive water barrier against Confederate raids. The flooded waterways also helped to shield Union enclaves at Lake Providence, Milliken's Bend, and Young's Point, LA.