Salvage Work on USS Nevada
First of the Pearl Harbor salvage team's major successes was the refloating of the battleship Nevada, which had suffered severely from a torpedo hit, plus many bomb hits and near misses. She had been deliberately run aground, gradually filled with water and settled to the bottom. Though "sunk" in relatively shallow water, Nevada presented significant challenges to her salvors: her hull had one large and many small holes that needed to be sealed sufficiently to get her into drydock; her interior was full of water and badly fouled with oil and other debris; and she had many compartments burned out. Most significantly, her deficiencies in watertight integrity, which had led to her sinking in the first place, now had to be made good under very difficult circumstances.
Work on Nevada began soon after the attack, and proceeded methodically over the next two months. The effort was not without tragedy. On 7 February 1942, as efforts to refloat the ship were about to bear fruit, two men lost their lives to hydrogen sulphide gas, a product of decay that is odorless in high concentrations and kills without warning. This unanticipated experience led to the imposition of stringent measures to reduce gas risks in the remaining salvage work.
Nevada was refloated on 12 February 1942 and entered Pearl Harbor Navy Yard's new Drydock Number Two on 18 February. Her salvage had involved more than 400 individual dives by Navy and civilian divers, who spent over 1500 hours on their work. Once the battleship was in their hands, the Navy Yard undertook the job of preparing Nevada for the trip to the U.S. west coast. Patching her holes, finishing cleaning, overhauling and repairing machinery and electrical systems and carrying out many other tasks took just over two more months.
Two types of patches were made by the Pearl Harbor Navy Yard to help in refloating Nevada. A large patch, intended to cover the large torpedo hole in the battleship's port side, proved unsatisfactory, since the ship's hull was too badly distorted to permit the patch to seal the hole. After much work, this patch had to be removed before Nevada was placed in drydock. More successful were smaller "window frame" patches that were used to close up underwater bomb damage.
She came out of drydock on 15 March and was ready to sail on 22 April. After steaming under her own power to Puget Sound Navy Yard, at Bremerton, Washington, USS Nevada underwent permanent repair and modernization work. She rejoined the active fleet in late 1942.