Tsunami Resistant Harbor
As of 2014, Crescent City Harbor district officials say that Crescent City Harbor is the first tsunami-resistant harbor in the western hemisphere. Crescent City Harbors boat basin has been designed to resist a 50-year tsunami event (the type of tsunami expected once every 50 years). By design, the docks, pilings and pile guides are designed to withstand the forces that come with quickly rising and falling water during tsunami surges.
Providing one of the main components for this resistance are the 30-inch-wide steel pilings that have been drilled at least 30 feet into the bedrock. According to Harbor Master Richard Young, stress tests on docks and pilings during both high and low tide have found current harbor exceeds the strength outlined in the development design specifications.
Another component of the harbor design, the interior docks are extra strong. The docks were built with massive concrete modules, and they attach to the pilings with 600-pound pile guides made of galvanized steel.
A final crucial component making the marina tsunami-resistant is a "wave attenuator" designed to decrease the force of a tsunami surge. The 400-foot-long H Dock is the first dock a surge would hit at the entrance of the harbor. It's 7 feet tall, but like an iceberg, the bulk of the dock hangs below the surface. Each 39-foot by 16-foot section of H Dock weighs 160,000 pounds. This feature creates a massive wall of concrete that should slow down most tsunami surges. To Add to the strength of Dock H, the pilings are close together, sometimes only an arm-span separation. The result is a massive wall of defense that will help decrease the force of tsunami surge and help tame the tsunami action.