The water level inside of National Steel and Shipbuilding Company's floating dry dock holds at 25 feet while engineers make final damage control checks before the amphibious assault ship USS Boxer is floated free of the dock floor and returned to its home pier at Naval Base San Diego, April 1, 2010. Boxer spent more than four months in dry dock as part of a Dry Dock Planned Maintenance Availability to complete essential repairs and install upgrades throughout the ship.