Photos courtesy AGC of Washington The Navy's pier at Silverdale was upgraded to handle a nuclear submarine.

The pier upgrade and building addition houses the latest Seawolf class nuclear submarine USS Jimmy Carter, the largest and most expensive espionage vessel ever built at 453 feet long and $3.2 billion.

The GCC/WPC joint venture included more than 176,000 labor hours and over 80 subcontractors and suppliers. At least 230 change orders and 750 requests for information were made to address the needs of the owner. The project’s schedule was tight because the facility needed to be complete in order to dock the submarine that was out to sea for testing.

The project included a building addition and two new buildings, including this office/support facility on the pier.

One major concern was working within the fish window restriction period. During the pile driving operation, special measures such as a bubble curtain, hydro-acoustic noise monitoring and underwater diver monitoring were used. The bubble curtain creates a wall of air surrounding the piles as they are driven, absorbing sound waves that are extremely dangerous to juvenile fish.

Vegetable hydraulic oil was used in the vibratory pile hammers.

The project required managing work on a highly secure construction site which included access to the base, special clearance into the restricted operational area, and special individual badges for full access to the site. Limited access created a logistical and sequencing challenge for subcontractors.

The project had only one lost-time accident, a soft tissue injury.