An age-old challenge to the human ingenuity and engineering science was met in completion of the Golden Gate Bridge. Today, some call it the "most spectacular bridge in the world." However, a century ago, building the bridge appeared to be an impossible task. Any bridge in this location would have to withstand brutal winds, tide, and fog. It would also sit less than eight miles from the epicenter of the most catastrophic earthquake in history.
Only one engineer was willing to gamble that his bridge could withstand such destructive power. His name was Joseph Strauss.
The Golden Gate Bridge's 4,200-foot main suspension span became a world record that stood for 27 years. The bridge's two towers rise 746 feet, making them 191 feet taller than the Washington Monument. The five-lane bridge crosses Golden Gate Strait, which is about 400 feet deep.
The bridge's design reflects a distinct Art Deco style. Wide, vertical ribbing on the horizontal tower bracing accents the sun's light on the bridge. The towers that support the Golden Gate Bridge's suspension cables are smaller at the top than at the base, which emphasizes the tower height of 500 feet above the roadway.*
In April 1865, the Civil War ended and masses of soldiers demobilized, many of whom soon moved west. In 1872, entrepreneur Charles Crocker presented plans and cost estimates for a bridge spanning the Golden Gate, where San Francisco Bay meets the Pacific Ocean. On April 18, 1906, San Francisco was devastated by a destructive earthquake. Two-thirds of the city's population, about 250,000 people, became homeless.
In 1916, James H. Wilkins, a structural engineer, proposed the first serious design for spanning the Golden Gate. He campaigned for a bridge and caught the attention of San Francisco City Engineer Michael M. O'Shaughnessy. O'Shaughnessy consulted engineers about feasibility and cost. The majority speculated that a bridge would cost more than $100 million. Joseph Strauss, who had designed nearly 400 spans, claimed it could be built for only $25 to $30 million.
In November 1918, the San Francisco Board of Supervisors asked Congress to authorize a federal survey of the Golden Gate channel. In January 1920, at the city engineer's request, the U.S.S. Natoma sounded the Golden Gate channel. Then in May, O'Shaughnessy received the Natoma's survey data. He sent it to three nationally known engineers: Joseph Strauss in Chicago, Francis C. McMath in Detroit, and Gustav Lindenthal of Metuchen, New Jersey.
On June 28, 1921, O'Shaughnessy considered the engineers' proposals. Lindenthal had estimated a minimal cost of $56 million, thereby disqualifying himself as too expensive. McMath never officially responded. Strauss submitted preliminary sketches to O'Shaugnessy with an estimate of $27 million.
As the land owner on both sides of the Golden Gate, the War Department was the only entity that could authorize construction. The department also held jurisdiction over all harbor construction that might affect shipping traffic or military logistics. San Francisco and Marin counties submitted a joint application for a permit to build the bridge. On December 24, Secretary of War John W. Weeks issued a temporary permit.
On December 4, 1928, the Association of Counties formed the Golden Gate Bridge and Highway District to finance, design, and construct the bridge. The district consisted of San Francisco, Marin, Sonoma, Del Norte, and parts of Mendocino and Napa counties.
In August 1929, Joseph B. Strauss was chosen as the bridge's chief engineer. Leon S. Moisseiff, O.H. Amman and Charles Derleth Jr. were named consulting engineers. Later that summer, Strauss abandoned his initial plan to build a cantilever-suspension bridge and decided on an all-suspension bridge design.
Then on October 29, the stock market crashed, and the nation's financial doldrums worsened while more than 15 million Americans, a quarter of the work force, lost their jobs.
In February 1930, Strauss submitted a formal report to the bridge's directors, accounting for changes that included the conversion to an all-suspension bridge. On March 1, Charles Ellis returned to Chicago to begin the preliminary design and estimate. Ellis completed the overall design in four months.
During the summer of 1930, Strauss hired a local architect, Irving Morrow, to design an architectural treatment for the bridge. Morrow would later be recognized for his aesthetic contributions: the Golden Gate Bridge's distinctive Art Deco lines, burnt red-orange hue, and the structure's dramatic lighting.
On August 11, the War Department issued the final permit. On August 27, 1930, Joseph Strauss submitted his 285-page final plan to the District's board of directors, two months behind schedule. In November, as the country endured the Great Depression, the bridge's board proposed that voters underwrite the major construction of the Golden Gate Bridge. On November 4, voters from the six counties of the District agreed to a $35 million bond issue; the vote was 145,657 in favor and 46,954 against.
Ellis began the thousands of detailed calculations involving suspension ropes, decks, floor beams, highway track, cables, towers, and more. Ellis wrote the specifications for all 10 construction contracts, covering everything from cable wire to suspender ropes to concrete for the anchorages.
More than one million tons of concrete were used to build the anchors, the massive blocks that grip the bridge's supporting cables. The north pier, which supports the tower, was built easily on a bedrock ledge just 20 feet below the water, but on the southern San Francisco side, the pier had to be built in the open ocean, 100 feet below the surface. Strauss built a huge, watertight cofferdam; the cofferdam was big enough to enclose a football field, and pumped in hundreds of tons of concrete. By 1935, the towers were complete, and cable spinning began. Two years later, the bridge was finished.
Strauss completed the $27 million bridge just five months after the promised date and $1.3 million under budget. For his efforts, Strauss received $1 million and a lifetime bridge pass.
*See Coast Highway 101 in Oregon .
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