Client: Phillips Petroleum Co.
Owner: Phillips Petroleum Co.
Cost of Work: $10 million

The design and construction of innovative submersible bridges on the North Slope of Alaska saved the owner approximately 50 percent ($10 million) over the cost of elevated bridges for the crossing of two river channels in a flood plain nearly 2 miles wide. Extreme envi-ronmental conditions, design vehicle weights approaching 4 million pounds, impact loading from river ice 5 feet thick and discontinuous permafrost soil conditions posed interesting and unusual design and construction challenges. The strength, resiliency and construction flexibility of welded steel were keys to providing the most cost-effective solution for this project.