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87-406: The name Carquinez Bridge originally referred to a single cantilever bridge built in 1927, which was part of the direct route between San Francisco and Sacramento . A second parallel cantilever bridge was completed in 1958 to deal with the increased traffic. Later, seismic problems made the 1927 span unsafe in case of an earthquake, and led to the construction, and 2003 opening, of a replacement:

174-559: A suspension bridge officially named the Alfred Zampa Memorial Bridge , in memory of iron worker Al Zampa , who played an integral role in the construction of numerous San Francisco Bay Area bridges. The Alfred Zampa Memorial Bridge carries southbound traffic from Vallejo to Crockett, and the 1958 cantilever span carries northbound traffic. The first regular crossing of the Carquinez Strait began in

261-503: A bridge had a widespread public and political appeal. Yet the task was too much of an engineering and economic challenge, since the bay was too wide and too deep there. In 1921, more than forty years after Norton's death, an underground tube was considered, but it became clear that one would be inadequate for vehicular traffic. Support for a trans-bay crossing increased in the 1920s based on the popularity and availability of automobiles. The California State Legislature and governor enacted

348-664: A cantilever bridge. The Forth Bridge is a notable example of an early cantilever bridge. This bridge held the record for longest span in the world for twenty-nine years until it was surpassed by the Quebec Bridge . The engineers responsible for the bridge, Sir Benjamin Baker and Sir John Fowler , demonstrated the structural principles of the suspended span cantilever by sitting in chairs and supporting their colleague, Kaichi Watanabe , in between them, using just their arms and wooden poles. The suspended span, where Watanabe sits,

435-462: A center anchorage. Rincon Hill is the western anchorage and touch-down for the San Francisco landing of the bridge connected by three shorter truss spans. The eastern crossing, between Yerba Buena Island and Oakland, was a cantilever bridge with a double-tower span, five medium truss spans, and a 14-section truss causeway . Due to earthquake concerns, the eastern crossing was replaced by

522-554: A cost of $ 240 million a new suspension bridge was built, to the west of the two earlier bridges, by the joint venture consisting of Flatiron Structures of Longmont, Colorado, FCI Constructors of Benicia, California, and the Cleveland Bridge & Engineering Company of Darlington, England. This new bridge was named the Alfred Zampa Memorial Bridge , after an ironworker who worked on a number of

609-505: A dynamite blast on the eastern side of the island at 12:58 p.m. local time. Former President Herbert Hoover and Governor James Rolph were onsite; the two men were the first to turn over the earth with ceremonial golden spades. Other ceremonies took place simultaneously in San Francisco (on Rincon Hill ) and Oakland Harbor. The Yerba Buena Tunnel opened, along with the rest of the Bay Bridge, on November 12, 1936. As of 2019,

696-604: A former U.S. Congressman from California, traveled to Washington to help persuade President Herbert Hoover and the Reconstruction Finance Corporation to advance $ 62 million to build the bridge. Before work began, 12 massive underwater telephone cables were moved 1,000 feet (300 m) of the proposed bridge route by crews of the Pacific Telephone and Telegraph Co. during the summer of 1931. Construction began on July 9, 1933 after

783-418: A groundbreaking ceremony attended by former president Herbert Hoover , dignitaries, and local beauty queens. The western section of the bridge between San Francisco and Yerba Buena Island presented an enormous engineering challenge. The bay was up to 100 feet (30 m) deep in places and the soil required new foundation-laying techniques. A single main suspension span some 4,100 feet (1.2 km) in length

870-507: A hinge in the girder. Heinrich Gerber was one of the engineers to obtain a patent for a hinged girder (1866) and is recognized as the first to build one. The Hassfurt Bridge over the Main river in Germany with a central span of 124 feet (38 metres) was completed in 1867 and is recognized as the first modern cantilever bridge. The High Bridge of Kentucky by C. Shaler Smith (1877),

957-751: A law, effective in 1929, to establish the California Toll Bridge Authority (Stats. 1929, Chap 763) and to authorize it and the State Department of Public Works to build a bridge connecting San Francisco and Alameda County (Stats. 1929, Chap 762). The state appointed a commission to evaluate the idea and various designs for a bridge across the Bay, the Hoover-Young Commission . Its conclusions were made public in 1930. In January 1931, Charles H. Purcell ,

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1044-405: A major engineering breakthrough when first put into practice, as it can span distances of over 1,500 feet (450 m), and can be more easily constructed at difficult crossings by virtue of using little or no falsework . Engineers in the 19th century understood that a bridge that was continuous across multiple supports would distribute the loads among them. This would result in lower stresses in

1131-425: A new crossing that opened on Labor Day 2013. On Yerba Buena Island, the double-decked crossing is a 321-foot (98 m) concrete viaduct east of the west span's cable anchorage, the 540-foot (160 m) Yerba Buena Tunnel through the island's rocky central hill, another 790.8-foot (241.0 m) concrete viaduct, and a longer curved high-level steel truss viaduct that spans the final 1,169.7 feet (356.5 m) to

1218-608: A new museum to be built at the Oakland end of the San Francisco–Oakland Bay Bridge . At a cost of $ 38 million a parallel bridge was built just east of the 1927 bridge. The new bridge carried all traffic for a few months after it opened in November 1958, then after new ramps were built, the three-lane 1927 span, originally two-way, served westbound traffic while the four-lane 1958 span handled eastbound traffic. At

1305-550: A pin, usually after forcing the union point apart, and when jacks are removed and the bridge decking is added the bridge becomes a truss arch bridge . Such unsupported construction is only possible where appropriate rock is available to support the tension in the upper chord of the span during construction, usually limiting this method to the spanning of narrow canyons. World's longest cantilever bridges (by longest span): San Francisco%E2%80%93Oakland Bay Bridge The San Francisco–Oakland Bay Bridge , commonly referred to as

1392-559: A project which created the artificial Treasure Island . The contract to build the Yerba Buena Cable Anchorage, Tunnel & Viaduct segment was opened for bids on March 28, 1933, and awarded to the low bidder, Clinton Construction Company of California, for $ 1,821,129.50 (equivalent to $ 34 million in 2023 ). Yerba Buena Island was the main site of the official groundbreaking for the Bay Bridge on July 9, 1933, when President Franklin D. Roosevelt remotely set off

1479-421: Is 76 feet (23 m) wide and 58 feet (18 m) high overall, and the dimensions of the tunnel interior are 66 feet (20 m) wide and 53 feet (16 m) high. In 1936, it was hailed as the world's largest-bore tunnel. The cross-sectional area of the upper half is 1,500 square feet (140 m ), and the lower half is 1,000 square feet (93 m ). Reminders of the long-gone bridge railway survive along

1566-400: Is a bridge built using structures that project horizontally into space, supported on only one end (called cantilevers ). For small footbridges , the cantilevers may be simple beams ; however, large cantilever bridges designed to handle road or rail traffic use trusses built from structural steel , or box girders built from prestressed concrete . The steel truss cantilever bridge was

1653-505: Is formed by two cantilever arms extending from opposite sides of an obstacle to be crossed, meeting at the center. In a common variant, the suspended span , the cantilever arms do not meet in the center; instead, they support a central truss bridge which rests on the ends of the cantilever arms. The suspended span may be built off-site and lifted into place, or constructed in place using special travelling supports. A common way to construct steel truss and prestressed concrete cantilever spans

1740-424: Is in the center. The wooden poles resist the compression of the lower chord , while the outstretched arms support the tension of the upper chord. The placement of the brick counterweights demonstrates the action of the outer foundations. Cantilever Bridge.—A structure at least one portion of which acts as an anchorage for sustaining another portion which extends beyond the supporting pier. A simple cantilever span

1827-532: Is in use as an access to the EBMUD treatment plant) and onto 40th St. Due to falling ridership, Sacramento Northern and IER service ended in 1941. On September 13, 1942, a stop was opened at Yerba Buena Island to serve expanded wartime needs on adjacent Treasure Island. Despite the vital role the railroad played, the last train went over the bridge in April 1958. The tracks were removed and replaced with pavement on

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1914-483: Is paid within 21 days. Crossing the original 1927 bridge required a toll, but tolls were removed soon after the state bought the bridge in 1940. Tolls in 1926 were originally set at $ 0.60 per car plus $ 0.10 per passenger. This was reduced in 1938 to $ 0.45 per car plus $ 0.05 per passenger. After the state took ownership, tolls were immediately reduced to $ 0.30 per car. In 1942, tolls were further reduced to $ 0.25 before being removed in 1945. Tolls were reinstated in 1958 with

2001-405: Is to counterbalance each cantilever arm with another cantilever arm projecting the opposite direction, forming a balanced cantilever ; when they attach to a solid foundation, the counterbalancing arms are called anchor arms . Thus, in a bridge built on two foundation piers, there are four cantilever arms: two which span the obstacle, and two anchor arms that extend away from the obstacle. Because of

2088-797: The Bay Bridge , is a complex of bridges spanning San Francisco Bay in California . As part of Interstate 80 and the direct road between San Francisco and Oakland , it carries about 260,000 vehicles a day on its two decks. It includes one of the longest bridge spans in the United States . The toll bridge was conceived as early as the California gold rush days, with "Emperor" Joshua Norton famously advocating for it, but construction did not begin until 1933. Designed by Charles H. Purcell , and built by American Bridge Company , it opened on Thursday, November 12, 1936, six months before

2175-578: The COVID-19 pandemic , all-electronic tolling was placed in effect for all seven state-owned toll bridges. The MTC then installed new systems at all seven bridges to make them permanently cashless by the start of 2021. In April 2022, the Bay Area Toll Authority announced plans to remove all remaining unused toll booths and create an open-road tolling system which functions at highway speeds. Cantilever bridge A cantilever bridge

2262-522: The Departments of War , Navy , and Commerce . The state applied for permits from the 3 federal departments as required. The permits were granted in January 1932, and formally presented in a ceremony on Yerba Buena Island on February 24, 1932. On May 25, 1931, Governor James Rolph Jr. signed into law two acts: one providing for the financing of state bridges by revenue bonds, and another creating

2349-570: The George Washington Bridge had a longer span between towers. As part of the celebration a United States commemorative coin was produced by the San Francisco Mint . A half dollar , the obverse portrays California's symbol, the grizzly bear , while the reverse presents a picture of the bridge spanning the bay. A total of 71,369 coins were sold, some from the bridge's tollbooths. The Yerba Buena passage utilizes

2436-528: The Golden Gate Bridge . It originally carried automobile traffic on its upper deck, with trucks, cars, buses and commuter trains on the lower, but after the Key System abandoned its rail service on April 20, 1958, the lower deck was converted to all-road traffic as well. On October 12, 1963, traffic was reconfigured to one way traffic on each deck, westbound on the upper deck, and eastbound on

2523-408: The Key System . Freight trains never used the bridge. The tracks left the lower deck in San Francisco just southwest of the end of 1st St. They then went along an elevated viaduct above city streets, looping around and into the terminal on its east end. Departing trains exited on the loop back onto the bridge. The loop continued to be used by buses until the terminal's closure in 2010. The tracks left

2610-547: The Niagara Cantilever Bridge by Charles Conrad Schneider (1883) and the Poughkeepsie Bridge by John Francis O'Rourke and Pomeroy P. Dickinson (1889) were all important early uses of the cantilever design. The Kentucky River Bridge spanned a gorge that was 275 feet (84 metres) deep and took full advantage of the fact that falsework, or temporary support, is not needed for the main span of

2697-660: The Transcontinental Railroad that preceded it nearly sixty years earlier, chose to avoid crossing the Carquinez Strait entirely. The preferred option, given the engineering limitations of the day, was to skirt around the Delta by going south from Sacramento through Stockton , then proceeding west across the San Joaquin River and over the Altamont Pass , and finally reaching Oakland from

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2784-563: The Yerba Buena Tunnel , also known as the Yerba Buena Island Tunnel . The tunnel is 76 feet (23 m) wide, 58 feet (18 m) high, and 540 feet (160 m) long. It is the largest diameter transportation bore tunnel in the world. The large amount of material that was excavated in boring the tunnel was used for a portion of the landfill over the shoals lying adjacent to Yerba Buena Island to its north,

2871-462: The median of the road for bridge employees; the parking lot is about 1,900 feet (580 m) long, stretching from about 800 feet (240 m) east of the toll plaza to about 100 feet (30 m) west of the metering lights. During the morning commute hours, traffic congestion on the westbound approach from Oakland stretches back through the MacArthur Maze interchange at the east end of

2958-406: The 1958 eastbound span underwent a seismic retrofit, deck and superstructure rehabilitation, and painting to extend its serviceable life. The old 1927 cantilever bridge was dismantled three years after the opening of its replacement; with completion on September 4, 2007. A 3,000-pound bronze bell atop one of the bridge piers was removed and placed into storage. The bell will eventually be displayed in

3045-543: The Bay Area Toll Authority again raised tolls on all seven of the state-owned bridges in July 2010. The toll rate for autos on the Carquinez Bridge was thus increased to $ 5. In June 2018, Bay Area voters approved Regional Measure 3 to further raise the tolls on all seven of the state-owned bridges to fund $ 4.5 billion worth of transportation improvements in the area. Under the passed measure, the toll rate for autos on

3132-494: The Bay Bridge, including the construction of the Yerba Buena Tunnel. Before starting excavation, the ground through which the western half of the tunnel would be bored was stabilized by injecting cement grout under pressure through 25 1.5-inch (38 mm) holes bored into the loose rock over the crown of the tunnel. After excavating the western and eastern open portals, three drifts were bored from west to east along

3219-516: The Board of Supervisors, in which compromise with the Central Pacific was recommended; also the bridging of the bay at Ravenswood and the granting of railroad facilities at Mission Bay and on the water front. Wm. C. Ralston, ex-Mayor Selby and James Otis were on this committee. A daily newspaper attempts to account for the advice of these gentlemen to the city by hinting that they were afraid of

3306-594: The CIDH pile at the South Tower is approximately 89 m, with about 43 m of drilled shaft in rock. The total length of the CIDH pile at the North Tower ranges from 49 to 64 m, with about 16 to 26 m of drilled shaft in rock. The design parameters used for the South Tower piles were later confirmed by a pile load test. Additional field investigations during construction revealed significant variations in rock conditions at

3393-466: The Carquinez Bridge will be increased to $ 6 on January 1, 2019; to $ 7 on January 1, 2022; and then to $ 8 on January 1, 2025. In September 2019, the MTC approved a $ 4 million plan to eliminate toll takers and convert all seven of the state-owned bridges to all-electronic tolling , citing that 80 percent of drivers are now using FasTrak and the change would improve traffic flow. On March 20, 2020, accelerated by

3480-564: The Carquinez Bridge, and along the shores of the San Pablo and San Francisco bays to Richmond and Oakland; becoming U.S. Route 40 , and ultimately Interstate 80 . After the Loma Prieta earthquake engineers determined that the aging 1927 span was seismically unstable, and that a retrofit was impossible. The decision was made to replace it with a new suspension bridge. The 1927 span was temporarily used to hold eastbound traffic while

3567-471: The North Tower, resulting in the redesign of the length of the piles. Major construction challenges encountered during construction of the South Tower piles, and the revised construction procedure, i.e., under-reaming, used by the constructor to mitigate caving. Materials for the New Bridge came from all over the world: Tolls are collected only from automotive traffic headed eastbound, towards Vallejo at

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3654-527: The San Francisco Bay Area bridges, including the Golden Gate Bridge , and the original 1927 Carquinez span. The bridge was dedicated on November 8, 2003, and opened for traffic on November 11, 2003. Originally, the plan was to dedicate the bridge on November 15, but complications involving then just-recalled Governor Gray Davis and the transfer of power to Arnold Schwarzenegger resulted in the date being moved. The coins minted to commemorate

3741-487: The San Francisco entrance to the bridge, was jammed with a slowly moving auto caravan. Every available policeman in the department was called to duty to aid in regulating the city's greatest parade of autos. One of the greatest traffic congestions of the evening was at Fifth and Mission Streets, with downtown traffic and bridge-bound traffic snarled in an almost hopeless mass. To add to the confusion, traffic signals jammed and did not synchronize. Police reported that there

3828-524: The San Francisco–Oakland Bay Bridge Division of the State Department of Public Works. On September 15, 1931, this new division opened its offices at 500 Sansome Street in San Francisco. During 1931, numerous aerial photographs were taken of the chosen route for the bridge and its approaches. That year, engineers had not determined the final design concept for the western span between San Francisco and Yerba Buena Island, although

3915-554: The State Highway Engineer of California, who had also served as the secretary of the Hoover-Young Commission, assumed the position of Chief Engineer for the Bay Bridge. Glenn B. Woodruff served as design engineer for the project. He explained in a 1936 article that several elements of the bridge required not only new designs, but also new theories of design. To make the bridge feasible, a route

4002-411: The bay to Oakland was spanned by a 10,176-foot (3.102 km) combination of double cantilever, five long-span through-trusses, and a truss causeway, forming the longest bridge of its kind at the time. The cantilever section was longest in the nation and third-longest anywhere. Much of the original eastern section was founded upon treated wood pilings. Because of the very deep mud on the bay bottom, it

4089-404: The bridge onto the three feeder highways, Interstate 580 , Interstate 880 , and I-80 toward Richmond . Since the number of lanes on the eastbound approach from San Francisco is structurally restricted, eastbound backups are also frequent during evening commute hours. The eastbound bottleneck is not the bridge itself, but the approach, which has just three lanes in each direction, in contrast to

4176-733: The bridge was built however, driving from Sacramento to the East Bay became much more direct. The Carquinez Bridge provided a welcome alternative route from the Central Valley to the Bay Area , one that no longer required loading one's vehicle onto and off of a ferry. With the bridge completed, the Lincoln Highway was realigned to cross the Sacramento River , then proceed southwest through Davis and Vallejo , across

4263-455: The bridge's five. The western section of the Bay Bridge is currently restricted to motorized freeway traffic. Pedestrians, bicycles, and other non-freeway vehicles are not allowed to cross this section. A project to add bicycle/pedestrian lanes to the western section has been proposed but is not finalized. A Caltrans bicycle shuttle operates between Oakland and San Francisco during peak commute hours for $ 1.00 each way. Freeway ramps next to

4350-423: The bridge, the new eastern section is a single deck carrying all eastbound and westbound lanes. Demolition of the old east span was completed on September 8, 2018. The bridge consists of two crossings, east and west of Yerba Buena Island , a natural mid-bay outcropping inside San Francisco city limits. The western crossing between Yerba Buena and downtown San Francisco has two complete suspension spans connected at

4437-553: The cantilever bridge. The toll plaza on the Oakland side (westbound traffic only since 1969) has eighteen toll lanes, with all charges now made either through the FasTrak electronic toll collection system or through invoices mailed through the USPS , based on the license plate of the car per Department of Motor Vehicle records. Metering signals are about 1,000 feet (300 m) west of the toll plaza. Two full-time bus-only lanes bypass

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4524-703: The city would lose its position as the regional center of trade. Businessmen had considered the concept of a bridge spanning the San Francisco Bay since the Gold Rush days. During the 1870s, several newspaper articles explored the idea. In early 1872, a "Bay Bridge Committee" was hard at work on plans to construct a railroad bridge. The April 1872 issue of the San Francisco Real Estate Circular reported on this committee: The Bay Bridge Committee lately submitted its report to

4611-524: The completion of the parallel span, set again at $ 0.25. It was increased to $ 0.35 in 1970, and then $ 0.40 in 1978. The basic toll (for automobiles) on the seven state-owned bridges, including the Carquinez Bridge, was raised to $ 1 by Regional Measure 1, approved by Bay Area voters in 1988. A $ 1 seismic retrofit surcharge was added in 1998 by the state legislature, originally for eight years, but since then extended to December 2037 (AB1171, October 2001). On March 2, 2004, voters approved Regional Measure 2, raising

4698-422: The construction of the Bay Bridge was part of the upper deck lining in late summer 1936. This included the emplacement of regularly spaced refuge bays ("deadman holes") along the south wall of the lower deck tunnel, escape alcoves common in all railway tunnels into which track maintenance workers could duck if a train came along. These remain and are visible to eastbound motorists today. The completed tunnel bore

4785-519: The entrance to the bay, San Francisco was well placed to prosper during the California Gold Rush . Almost all goods not produced locally arrived by ship, as did numerous travelers and erstwhile miners. But after the first transcontinental railroad was completed in May 1869, San Francisco was on the wrong side of the Bay, and separated from the new rail link. Many San Franciscans feared that

4872-742: The event have the original date on them. The new suspension bridge, consists of the south anchorage, a transition pier, the South and North towers, and the north anchorage. It has spans of 147 m, 728 m, and 181 m. for a total span of 0.66 miles (1,060 m). It features a pedestrian and bicycle path, part of a bike trail which it is hoped will eventually circle the entire Bay Area . The towers are each founded on two footings, which are each supported by six vertical, 3-metre-diameter (9.8 ft) steel shells infilled with reinforced concrete, followed by 2.7-metre-diameter (8.9 ft) drilled shafts in rock, i.e., cast-in-drilled hole, or CIDH, piles. The total length of

4959-555: The former US president Herbert Hoover , Senator William G. McAdoo , and the Governor of California , Frank Merriam . Governor Merriam opened the bridge by cutting gold chains across it with an acetylene cutting torch . The San Francisco Chronicle report of November 13, 1936, read: the greatest traffic jam in the history of S.F., a dozen old-fashioned New Year's eves thrown into one – the biggest and most good-natured crowd of tens of thousands ever to try and walk

5046-410: The girder or truss and meant that longer spans could be built. Several 19th-century engineers patented continuous bridges with hinge points mid-span. The use of a hinge in the multi-span system presented the advantages of a statically determinate system and of a bridge that could handle differential settlement of the foundations. Engineers could more easily calculate the forces and stresses with

5133-434: The idea of a double-span suspension bridge was already favored. In April 1932, the preliminary final plan and design of the bridge was presented by Chief Engineer Charles Purcell to Col. Walter E. Garrison, Director of the State Department of Public Works, and to Ralph Modjeski , head of the Board of Engineering Consultants. Both agencies approved and preparation of the final design proceeded. In 1932, Joseph R. Knowland ,

5220-430: The lower deck and the bridge was closed for a month. Reconstruction of the eastern section of the bridge as a causeway connected to a self-anchored suspension bridge began in 2002; the new eastern section opened September 2, 2013, at a reported cost of over $ 6.5 billion; the original estimate of $ 250 million was for a seismic retrofit of the existing span. Unlike the western section and the original eastern section of

5307-571: The lower deck in Oakland. The Interurban Electric Railway tracks ran along Engineer Road and over the Southern Pacific yard on trestles (some of it is still standing and visible from nearby roadways) onto the streets and dedicated right-of-ways in Berkeley, Albany, Oakland and Alameda. The Sacramento Northern and Key System tracks went under the SP tracks through a tunnel (which still exists and

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5394-514: The lower deck, with trucks and buses also allowed on the upper deck. In 1986, the bridge was unofficially dedicated to former California governor James Rolph . The bridge has two sections of roughly equal length; the older western section, officially known as the Willie L. Brown Jr. Bridge (after former San Francisco Mayor and California State Assembly Speaker Willie L. Brown Jr. ), connects downtown San Francisco to Yerba Buena Island , and

5481-479: The mid-1800s as a ferry operated between the cities of Benicia and Martinez, six miles upstream from the bridge site. Auto service started on this route in 1913. A train ferry operated between Benicia and Port Costa from 1879 until 1930 when a rail bridge opened. Ferry service at the site of the bridge started in 1913 by the Rodeo-Vallejo Ferry Company. The original steel cantilever bridge

5568-411: The need for more strength at the balanced cantilever's supports, the bridge superstructure often takes the form of towers above the foundation piers. The Commodore Barry Bridge is an example of this type of cantilever bridge. Steel truss cantilevers support loads by tension of the upper members and compression of the lower ones. Commonly, the structure distributes the tension via the anchor arms to

5655-402: The newer east bay section connects the island to Oakland. The western section is a double suspension bridge with two decks, westbound traffic being carried on the upper deck while eastbound is carried on the lower one. The largest span of the original eastern section was a cantilever bridge . During the 1989 Loma Prieta earthquake , a portion of the eastern section's upper deck collapsed onto

5742-609: The outermost supports, while the compression is carried to the foundations beneath the central towers. Many truss cantilever bridges use pinned joints and are therefore statically determinate with no members carrying mixed loads. Prestressed concrete balanced cantilever bridges are often built using segmental construction . Some steel arch bridges (such as the Navajo Bridge ) are built using pure cantilever spans from each side, with neither falsework below nor temporary supporting towers and cables above. These are then joined with

5829-400: The path of the tunnel: one at the crown and the other two at the lower corners. The first drift broke through in July 1934, approximately one year after the start of construction. A ceremonial party led by Governor Merriam celebrated the completion of the first 12-foot-square (3.7 m) drift on July 24 by walking through it, followed by a short speech. The space between the three drifts

5916-504: The railroad company, and therefore made their recommendations to suit its interests. The self-proclaimed Emperor Norton decreed three times in 1872 that a suspension bridge be constructed to connect Oakland with San Francisco. In the third of these decrees, in September 1872, Norton, frustrated that nothing had happened, proclaimed: WHEREAS, we issued our decree ordering the citizens of San Francisco and Oakland to appropriate funds for

6003-412: The south side of the lower Yerba Buena Tunnel. These are the regularly spaced refuge bays ("deadman holes"), escape alcoves common in all railway tunnels, along the wall, into which track maintenance workers could safely retreat if a train came along. (The north side, which always carried only motor traffic, lacks these holes.) The bridge opened on November 12, 1936, at 12:30 p.m. In attendance were

6090-443: The south; a route that would later become U.S. Route 50 and ultimately Interstates 5 , 205 , and 580 . This circuitous route, several miles longer, and traversing a rather formidable mountain pass, was preferable to crossing the Carquinez Strait, a deep channel with strong currents and frequent high winds. For decades, building a bridge across the Carquinez Strait was considered prohibitively expensive and technologically risky. Once

6177-426: The streets and guide their autos on them – This was the city last night, the night of the bridge opening with every auto owner in the bay region, seemingly, trying to crowd his machine onto the great bridge. And those who tried to view the brilliantly lighted structure from the hilltops and also view the fireworks display were numbered also in the thousands. Every intersection in the city, particularly those near

6264-633: The survey of a suspension bridge from Oakland Point via Goat Island; also for a tunnel; and to ascertain which is the best project; and whereas the said citizens have hitherto neglected to notice our said decree; and whereas we are determined our authority shall be fully respected; now, therefore, we do hereby command the arrest by the army of both the Boards of City Fathers if they persist in neglecting our decrees. Given under our royal hand and seal at San Francisco, this 17th day of September, 1872. Unlike most of Emperor Norton's eccentric ideas, his decree to build

6351-407: The toll booths and metering lights around the right (north) side of the toll plaza; other high occupancy vehicles can use these lanes during weekday morning and afternoon commute periods. The two far-left toll lanes are high-occupancy vehicle lanes during weekday commute periods. Radio and television traffic reports will often refer to congestion at the toll plaza, metering lights, or a parking lot in

6438-533: The toll by another dollar to a total of $ 3. An additional dollar was added to the toll starting January 1, 2007, to cover cost overruns concerning the replacement of the eastern span. The Metropolitan Transportation Commission , a regional transportation agency, in its capacity as the Bay Area Toll Authority , administers RM1 and RM2 funds, a significant portion of which are allocated to public transit capital improvements and operating subsidies in

6525-535: The toll plaza on the north side of the bridge. Although the 2003 Alfred Zampa Memorial Bridge is the newer span, no toll is charged in that direction, continuing the practice of the now-demolished 1927 span. All-electronic tolling has been in effect since 2020, and drivers may either pay using the FasTrak electronic toll collection device, using the license plate tolling program, or via a one time payment online. Effective January 1, 2022 – December 31, 2024  ( 2022-01-01  – 2024-12-31 ) ,

6612-411: The toll rate for passenger cars is $ 7. During peak traffic hours, carpool vehicles carrying three or more people, clean air vehicles, or motorcycles may pay a discounted toll of $ 3.50 if they have FasTrak and use the designated carpool lane. Drivers must pay within 48 hours after crossing the bridge or they will be sent a toll violation invoice. No additional fees will be added to the toll violation if it

6699-503: The transportation corridors served by the bridges. Caltrans administers the "second dollar" seismic surcharge, and receives some of the MTC-administered funds to perform other maintenance work on the bridges. The Bay Area Toll Authority is made up of appointed officials put in place by various city and county governments, and is not subject to direct voter oversight. Due to further funding shortages for seismic retrofit projects,

6786-548: The tunnel lacks an official name. Construction of the Bridge Railway began on November 29, 1937, with the laying of the first ties. The first train was run across the Bay Bridge on September 23, 1938, a test run utilizing a Key System train consisting of two articulated units with California Governor Frank Merriam at the controls. On January 14, 1939, the San Francisco Transbay Terminal

6873-428: The tunnel provide access to Yerba Buena Island and Treasure Island . Because the toll plaza is on the Oakland side, the western span is a de facto non-tolled bridge; traffic between the island and the main part of San Francisco can freely cross back and forth. Those who only travel from Oakland to Yerba Buena Island, and not the entire length to the main part of San Francisco, still must pay the full toll. Developed at

6960-414: The tunnel roof and lower deck was excavated using a power shovel. By May 1935, work on removing the core was progressing and 40 steel ribs had been placed; concrete embedment was just starting. Removal of the core was completed on November 18, 1935. Once the excavation was complete, the upper deck was placed and the interior ceiling above the upper deck was lined with tiles. The last concrete poured during

7047-440: Was chosen via Yerba Buena Island , which would reduce both the material and the labor needed. Since Yerba Buena Island was a U.S. Navy base at the time, the state had to gain approval from Congress for this purpose as it regulates and controls all federal lands and the armed services . After a great deal of lobbying, California received Congressional approval to use the island on February 20, 1931, subject to final approvals by

7134-418: Was considered but rejected, as it would have required too much fill and reduced wharfage space at San Francisco, had less vertical clearance for shipping, and cost more than the design ultimately adopted. The solution was to construct a massive concrete anchorage halfway between San Francisco and the island, and to build a main suspension span on each side of this central anchorage. East of Yerba Buena Island,

7221-608: Was dedicated. The following morning, January 15, 1939, the electric interurban trains started in revenue service, running along the south side of the lower deck of the bridge. The terminal originally was supposed to open at the same time as the Bay Bridge, but had been delayed. Trains over the Bridge Railway were operated by the Sacramento Northern Railroad ( Western Pacific ), the Interurban Electric Railway ( Southern Pacific ) and

7308-640: Was designed by Robinson & Steinman and dedicated on May 21, 1927. Prior to this, crossing the Carquinez Strait necessitated the use of ferries . The bridge cost $ 8 million to build. It was the first major crossing of the San Francisco Bay and a significant technological achievement in its time. Upon its completion, the span became part of the Lincoln Highway . This historic transcontinental roadway's original alignment, like

7395-436: Was no lessening of the traffic over the bridge, all lanes being crowded with Oakland- or San-Francisco-bound machines far into the night. The total cost was US$ 77 million. Before opening the bridge was blessed by Cardinal Secretary of State Eugene Cardinal Pacelli , later Pope Pius XII . Because it was in effect two bridges strung together, the western spans were ranked the second and third largest suspension bridges . Only

7482-428: Was not practical to reach bedrock, although the lower levels of the mud are quite firm. Long wooden pilings were crafted from entire old-growth Douglas fir trees, which were driven through the soft mud to the firmer bottom layers. The construction project had casualties: twenty-four men would die while constructing the bridge. California Department of Transportation engineer C.H. Purcell served as chief engineer for

7569-429: Was then excavated, resulting in a single arch-shaped bore (in cross-section), and the tunnel roof was constructed using 16-inch (410 mm) steel I-beam ribs spaced 3 feet (0.91 m) apart to support the rock, which were then embedded in concrete up to 3 feet (0.91 m) thick at the crown. No cave-ins occurred during the excavation of the tunnel. After the roof was completed, the remaining core of rock between

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