Bixby Creek Bridge, California: USA
Creek Bridge, also known as Bixby Bridge, is a reinforced concrete open-spandrel arch bridge in Big Sur, California. The bridge is located 120 miles (190 km) south of San Francisco and 13 miles (21 km) south of Carmel in Monterey County along California Highway One. Prior to the opening of the bridge in 1932, residents of the Big Sur area were virtually cut off during winter due to the often impassable Old Coast Road that led 11 miles (18 km) inland. At its completion, the bridge was built under budget for $199,861 and was the longest concrete arch span at 320 feet (98 m) on the California State Highway System.
History
Beginning in about 1855, travelers followed a very rough and dangerous track from Carmel south towards Big Sur. At Bixby Creek, the road turned 11 miles (18 km) inland and then led to the Post Ranch on the Rancho El Sur.The 30 miles (48 km) trip could take three days by wagon or stagecoach.The single-lane road was closed in winter when it became impassable. Coast residents would occasionally receive supplies via a hazardous landing by boat from Monterey or San Francisco.Bixby Creek takes its name from Charles Henry Bixby, from Livingston County, New York, who arrived on the Monterey Peninsula in 1868. He purchased large tracts of land in the Big Sur area and harvested the lumber, producing shakes, shingles, railroad ties, trench posts and tan bark. He processed these through a sawmill built along the creek and shipped them from a landing he built on the coast.
After it was built, the bridge was at times referred to as the Rainbow Bridge. This stems from a nearby resort, Rainbow Lodge, which was operated for a period of time by an Army Captain, Howard Sharpe and his wife, Frida. After lumbering came to an end, the Sharpes bought the ranch in the Bixby Creek Canyon in 1919. Sharpe built a dirt road from the lodge up the canyon to Bixby Landing and another road down to the beach at the mouth of Bixby Creek. He sold part of his land to the state to form part of the bridge right of way in 1930.
Construction
The state first began building Route 56, or the Carmel-San Simeon Highway,to connect Big Sur to the rest of California in 1919. A number of bridges needed to be built, the largest among them across Bixby Creek. The engineers considered two alternatives to crossing the creek, either an inland route and a smaller bridge, or a coastal location and a larger bridge. The inland route necessitated a 890 feet (270 m) tunnel cutting though the Santa Lucia Mountains to a 250 feet (76 m) bridge upstream.The engineers selected the coast route because it was safer, more scenic, and least affected the environment.
California state highway engineer C.H. Purcell and bridge engineer and designer F.W. Panhorst considered whether to build a steel or concrete span. A steel bridge would cost more to build and maintain, as the sea air would require expensive ongoing maintenance and painting. A steel bridge was also less in keeping with the natural environment. They chose concrete, because it would reduce both construction and maintenance costs and also echoed the color and composition of the natural rock cliff formations in the area.The state awarded a contract for $203,334 in 1931 to the lower bidder, Ward Engineering Company of San Francisco, on August 13, 1931.Construction began on August 24, 1931, and the crews began 
pouring concrete on November 27.Eight hundred twenty-five trucks brought in 6,600 cubic yards (5,000 m3) cubic yards of concrete and 600,000 pounds of reinforcing steel.Douglas-fir for the arch falsework was transported from the railroad in Monterey over the narrow, one-way road to the bridge site and sand and gravel was supplied from a plant in Big Sur. When high waves threatened the foundation of the wooden falsework, construction was halted for a short time until winter storms abated.
The crews excavated 4,700 cubic yards (3,600 m3) of earth and rock, used 300,000 feet (91,000 m) of Douglas fir timber for the falsework, and consumed 45,000 sacks of cement. The cement was transported from Davenport near Santa Cruz, and from San Andreas.Material was transported across the canyon from platforms using slings suspended from a cable 300 feet (91 m) above the creek. The bridge was completed on October 15, 1932.At its completion, the bridge cost $199,861 and was the longest concrete arch span at 320 feet (98 m) on the California State Highway System. In 1937, after 18 years of construction and aided by New Deal funds and the use of convict labor, the paved two-lane road now known as Highway 1 was completed.
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