It took five more years for Route 1 along Big Sur to be completed in 1937 and shortly thereafter, California Sea Otters were discovered from this location in 1938. Registered as an Historic Landmark, the bridge recently underwent a retrofit for more stringent earthquake standards which have come into effect in the 70 years since it was constructed. Its slender deck and arch ribs appear almost transparent as it carries U.S. Route 1 through the scenic park. The crux of the design was the longitudinal post tensioning of the entire bridge deck from end to end. New shear keys laterally support the arch ribs at their crowns by linking them with the deck.
Arch bridges are one of the oldest types of bridges and have great natural strength.
Instead of pushing straight down, the weight of an arch bridge is carried outward along the curve of the arch to the supports at each end. These supports, called the abutments, carry the load and keep the ends of the bridge from spreading out. At the beginning of the 20th century, the region was home to profitable mills that processed lumber products and lime and shipped them north to San Francisco. Tourists resorts such as Rainbow Lodge thrived until acquisition for right of way and completion of Route 1 occurred around 1930. TPL will purchase this crown jewel of the Big Sur Coast, easily identified by the historic Bixby Bridge on Highway 1, to protect it from looming development.