Building the Red River Dam. Courtesy of the Library of Congress.
THE DAM WORKS
To the amazement of practically everybody except Bailey, the dam complex was working. By May 6, the water held by the dam had risen 4 feet. By May 8, the water level was up 5 feet 4 inches. Three of the lighter vessels even crossed the upper rapids and now waited behind the dam for the heavier gunboats. As the soldiers worked to finish the dam, the water continued to build until the pressure against the dam became tremendous. General Banks feared the pressure would soon burst the dam, and the next day, at around 5:30 in the morning, one officer “heard a great crashing in the direction of the dam. Jumping out of the blankets and slipping on my coat, cap, and boots, I ran down to the bank. The water was rushing through at a great rate” (Tyson May 9, 1864).
Two of the barges used in the dam had broken loose, and the water was gushing through. Porter, seeing the crisis, quickly ordered the gunboat Lexington to run the gap:
Porter’s fleet passing through Colonel Bailey’s Dam above Alexandria, May 1864. From Frank Leslie’s Illustrated Newspaper, July 16, 1864. Courtesy of the Library of Congress.
The Lexington succeeded in getting over the falls and then steered directly for the opening in the dam, through which the water was dashing so furiously that it seemed as if certain destruction would be her fate. Ten thousand spectators breathlessly awaited the result. She entered the gap with a full head of steam; passed down the roaring, rushing torrent; made several spasmodic rolls; hung for a moment, with a harsh, grating sound, on the rocks below; was then swept into deep water, and rounded to by the bank of the river. Such a cheer arose from that vast multitude of sailors and soldiers, when the noble vessel was seen in safety below the falls, as we had never heard before, and certainly have not heard since (Moore 1868:12).
The Lexington’s run was followed by the three gunboats waiting behind the dam. Had the rest of the fleet been prepared, all of the boats might have escaped at that time. However, the navy’s lack of confidence in the dam had given way to apathy, and as the released water rushed through the break, valuable time was wasted as the fleet gathered steam to attempt the run. Eventually, the water behind the dam fell and six gunboats still remained trapped.
But the Lexington’s adventure had proven that the dam could work, and troops confidently went back to work. Bailey worried that the dam would break again and decided to leave the 70-foot gap in the dam as it was. But this time he added smaller, lighter dams near the upper rapids. Like the dam sections at the lower rapids, both crib and tree dam methods were employed. These dams helped channel the water while reducing the pressure on the main dam. Thus, instead of relying on one dam to hold back the water until another run could be made, a series of dams were built to create a deep channel of water along the whole course of the shoals in that part of the Red River.