Southern Crossing (California)#Second proposals (1947): Parallel Bridge and Southern Crossing

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| caption = Proposed second Bay crossing termini:

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• 1947 (combinations of {{color box|#008|1|#fff|border=silver}}–{{color box|#008|4|#fff|border=silver}} & {{color box|#fb0|5|#000|border=silver}}–{{color box|#fb0|8|#000|border=silver}} but primarily {{color box|#008|3|#fff|border=silver}}–{{color box|#fb0|7|#000|border=silver}} and {{color box|#008|4|#fff|border=silver}}–{{color box|#fb0|8|#000|border=silver}}){{rp|viii}}
• 1954 ({{color box|#008|3|#fff|border=silver}}–{{color box|#fb0|8|#000|border=silver}})
• 1966 ({{color box|#fb0|7|#000|border=silver}}–{{color box|#fb0|8|#000|border=silver}}–{{color box|#008|9|#fff|border=silver}} & {{color box|#008|10|#fff|border=silver}}–{{color box|#fb0|11|#000|border=silver}}){{rp|2}}
• 1991 ({{color box|#fb0|11|#000|border=silver}}–{{color box|#008|12|#fff|border=silver}})

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| mark-title2 = Rincon Hill

| mark-coord3 = {{coord|37.759336|-122.386467}}

| mark-title3 = Potrero Point

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| mark-title4 = Candlestick Point

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The idea for the Southern Crossing dates back to the 1940s when several additional bridges across San Francisco Bay were studied.{{cite web | url=http://www.lib.berkeley.edu/news_events/bridge/unbuilt_1.html | title=Bridging the Bay: Unbuilt Projects: Additional Crossings | publisher=University of California, Berkeley Libraries | access-date=August 5, 2012}} After the Bay Bridge crossing opened in 1936, connecting Rincon Hill {{color box|#008|2|#fff|border=silver}} in San Francisco with the Key Mole {{color box|#fb0|5|#000|border=silver}} in Oakland via two high-level bridges and a tunnel through Yerba Buena Island, vehicle traffic exceeded estimates almost immediately; by 1945, even with gasoline rationing, traffic was 191% of the estimates made during planning, and would reach an average of 69,000 vehicles per day by 1946.{{rp|13}} A second crossing was deemed necessary and studies were initiated to determine the best location and configuration.

A study completed on November 18, 1941 conducted by a joint Army-Navy Board{{USBill|77|HR|158}} concluded that a high-level bridge between Hunters Point {{color box|#008|4|#fff|border=silver}} and Bay Farm Island {{color box|#fb0|8|#000|border=silver}} was feasible at an estimated cost of $53.2M.{{rp|15}} The high-level bridge was preferred to a low-level lift bridge.{{rp|I-2}} The western terminus would have been on the south side of the existing Hunters Point Naval Shipyard and the eastern terminus would be on the southwest shore of Bay Farm Island. However, no immediate need was identified for a new bridge, and the project was shelved.{{rp|15}}

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|quote={{pad|1.0em}}I personally believe that both crossings are needed and should be constructed as early as possible. I believe our plans should be projected on that premise. If it were financially possible to do so I would vote for their construction simultaneously. But it cannot be done. Any new crossing must be financed by revenue bonds and the experts who pass upon such matters advise that we could not sell the bonds of two crossings at one time.

|author= — Governor Earl Warren |source=Statement at the California Toll Bridge Authority Meeting, March 23, 1949{{rp|38}} }}

On January 25, 1947, another joint Army-Navy Board published a study which concluded that a combination of causeway and tube from San Francisco (near Army Street/Potrero Point {{color box|#008|3|#fff|border=silver}}) to Alameda {{color box|#fb0|7|#000|border=silver}} was preferred.{{USBill|79|HR|529}}{{cite report |url=https://oac.cdlib.org/search?style=oac4;titlesAZ=r;descriptions=show;idT=UCb108286575 |title=Report of Joint Army-Navy Board on an additional crossing of San Francisco Bay |date=1947 |publisher=Joint Army-Navy Board |access-date=1 July 2019}}{{rp|xii}} From Alameda, the route would run north through the Posey Street tube to a point in Oakland near the present-day western terminus of Interstate 980. This was essentially the same as alternative no. 12 from the contemporaneous California Department of Public Works (DPW) study.{{rp|I-4}} Both routes recommended by the two 1947 studies were endorsed by Charles H. Purcell, the director of the California DPW on November 10, 1947; however, because of limited budget, the more expensive Southern Crossing option would be built after the Parallel Bridge.{{rp|xii–xiii}}

During the development of the Joint Army-Navy Board study, a public meeting was held on August 13, 1946, where ten alternative alignments for a second crossing were suggested. One group, based in San Francisco, advocated for a low-level causeway allowing the extension of the transcontinental rail line from Oakland; another group, based in the East Bay, proposed a high-level span for automobiles only. The California state government, represented by engineer F. W. Panhorst, agreed with the East Bay group and further advocated that to provide the maximum reduction in traffic on the Bay Bridge, the western terminus should be on Telegraph Hill {{color box|#008|1|#fff|border=silver}} or Rincon Hill {{color box|#008|2|#fff|border=silver}}. The August 1946 meeting was also notable for the first public presentation of the Reber Plan, which called for an immense dike between San Francisco and Oakland {{convert|2000|ft}} wide, reclaiming {{convert|180000|acre}} of land from San Francisco Bay and eliminating the need for another bridge.{{cite news |url=https://cdnc.ucr.edu/?a=d&d=MT19460813.2.14 |title=Debate Site New Bridge Across Bay |newspaper=Madera Tribune |date=August 13, 1946 |access-date=2 July 2019}} The 1947 Joint Army-Navy Board considered 29 different alignments before concluding the causeway-tube was the preferred option.{{rp|I-3}}

The first of the California state government studies was published a week later, on January 31, 1947, which concluded that another trans-Bay crossing was feasible and recommended that it be located close to the existing Bay Bridge.{{cite report |url=https://archive.org/details/1947-bay-crossings/ |title=Report to the California Toll Bridge Authority, covering preliminary studies for an additional bridge between San Francisco and the East Bay Metropolitan Area |date=January 31, 1947 |author=Department of Public Works |publisher=California State Printing Office |access-date=28 June 2019}} This alignment was later named the Parallel Bridge.{{cite report |url=https://catalog.hathitrust.org/Record/001612694 |title=A report to Department of Public Works on additional toll crossings of San Francisco Bay |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |date=November 1948 |author=Tudor, Ralph A. |access-date=12 July 2016}}{{rp|xii}}

File:1947 Proposed Second Bay crossings.jpg

The main reason to duplicate the existing route was to provide immediate relief to Bay Bridge traffic; the crossing further south from Potrero Point {{color box|#008|3|#fff|border=silver}} to Alameda {{color box|#fb0|7|#000|border=silver}} was estimated to divert only 20% of existing traffic, and the southernmost proposal studied, from Hunters Point {{color box|#008|4|#fff|border=silver}} to Bay Farm Island {{color box|#fb0|8|#000|border=silver}}, was estimated to divert only 5% of existing traffic.{{rp|18}} The alternative western terminus at Telegraph Hill {{color box|#008|1|#fff|border=silver}} was rejected on the basis of existing traffic patterns and freeway connections, and the alternative eastern terminus on the S.P. or Oakland Mole {{color box|#fb0|6|#000|border=silver}} was rejected not only because it would require a long high-level span to avoid interference with the existing shipping channel, but also that such a span would also interfere with flight operations at Naval Air Station Alameda.{{rp|18}}

The 1947 study also determined the feasibility of extending existing railroad termini for the Western Pacific Railroad, Atchison, Topeka, and Santa Fe, and Southern Pacific from Oakland to San Francisco; of the three, SP already had the option of using the Dumbarton Cut-off, and WP and AT&SF used buses (for passengers) or ferries (for freight); both a high-level bridge and a tunnel were ruled out as the required grades for the high-level bridge could not be achieved without excessively long approaches, and the tunnel would require conversion to electric locomotives. However, a low-level bridge accommodating rail traffic was considered for the southernmost Hunters Point {{color box|#008|4|#fff|border=silver}} to Bay Farm Island {{color box|#fb0|8|#000|border=silver}} crossing as alternative no. 11.{{rp|20}}

Alternative no. 5 would have used parallel tubes on a continuous radius curve of {{convert|32000|ft|abbr=on|adj=on}}, providing the shortest overall distance at {{convert|31850|ft|abbr=on}}. Each concrete tube would be {{convert|38|ft|abbr=on}} in outer diameter, and would be built on land in segments, which would each be floated into position then sunk in place. Ventilation would be provided through the roadway space, connected to ventilation structures at the two termini.{{rp|104–105}} A similar underwater route, with termini at the Market Street subway (slightly north of Rincon Hill) and the S.P. Mole was eventually built as the Transbay Tube for BART in the 1960s.

Alternative no. 7 included what would have been the longest suspension bridge in the world for the western portion, slightly longer than the Golden Gate Bridge at {{convert|9600|ft|abbr=on}} long overall, composed of a {{convert|4800|ft|abbr=on}} main span flanked by two {{convert|2400|ft|abbr=on}} side spans. Of all the alternative options studied in 1947, no. 7 had the shortest distance to span on the western portion.{{rp|106}}

Four true southern crossings were studied in 1947 (alternatives no. 10, 10A, 11, and 12). 10 and 10A differed in the configuration of the lower deck; 10 called for two truck lanes and two railroad tracks, while 10A omitted the tracks entirely. Both 10/10A and 12 included the cost of an additional tube to augment the existing Posey tube from Alameda to Oakland,{{rp|108–109}} which was eventually constructed as the Webster Street tube in 1963. Alternative no. 11 devoted the lower deck entirely to four railroad tracks, as the anticipated vehicular traffic was low. It included a {{convert|500|ft|abbr=on|adj=on}} long vertical lift span.{{rp|110}} Alternative no. 12 would use four tunnels on the western half, each containing two lanes of traffic, approximately {{convert|6800|ft|abbr=on}} long overall to provide a wide navigation channel; the eastern portion of the crossing would be at the water's level, consisting of a trestle {{convert|6700|ft|abbr=on}} long and a mole {{convert|13500|ft|abbr=on}} long.{{rp|111}}

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The California Department of Public Works created the San Francisco Bay Toll Crossings Division in December 1947 to study the Parallel Bridge and Southern Crossing proposals in further detail.{{rp|I-4}} In 1948, the Toll Crossings Division reiterated that a southern crossing was "entirely feasible" but recommended the expansion of the existing Bay Bridge with the Parallel Bridge alignment instead, which could be completed in 1954 at an estimated cost of {{USD|155000000|1948|round=-5}}.{{cite news |url=https://cdnc.ucr.edu/?a=d&d=MT19481117.2.33 |title=Hearing Slated On Proposed New Bay Bridge Plan |agency=U.P. |newspaper=Madera Tribune |date=November 17, 1948 |access-date=28 June 2019}} Preliminary plans for both the Parallel Bridge and Southern Crossing were prepared in 1948, which were reviewed by a board of consulting engineers in 1949.{{cite report |url=https://archive.org/details/summaryofinforma1949cali |title=Summary of information on the proposal to build a parallel bridge across San Francisco Bay |date=July 1949 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=2 July 2019}}{{rp|2–3}}

Because both bridges could not be financed simultaneously, the California Toll Bridge Authority resolved to complete the plans for the Parallel Bridge on March 23, 1949.{{rp|3–4}} Local and state leaders failed to align their support on a single proposal. In May 1949, San Francisco mayor Elmer Robinson testified before the California State Assembly in support of the Southern Crossing.{{cite report |url=https://archive.org/details/caseforsouthernc7194sanf |title=The Case for the Southern Crossing |author=Robinson, Elmer E |date=May 7, 1949 |publisher=City & County of San Francisco |access-date=9 July 2019}} Director Purcell went before Congress in July 1949 to request permission to expand the right-of-way on Yerba Buena Island to allow construction of the Parallel Bridge.{{rp|3–4}} Work on both the Southern Crossing and Parallel Bridge projects was halted on June 30, 1950, after disputes about the priority, alignment, and purpose of a second bridge could not be reconciled. An attempt to revive a second trans-Bay crossing failed to pass the California State Legislature during the 1951 session.{{rp|I-5}}

At about the same time, architect Frank Lloyd Wright and engineer Jaroslav Joseph Polivka unveiled the reinforced concrete "Butterfly Wing" bridge in May 1949 before Bay Toll Crossings.{{cite book |chapter-url=https://books.google.com/books?id=zLzcDAAAQBAJ&pg=PA87 |title=Frank Lloyd Wright and San Francisco |author=Turner, Paul Venable |date=2016 |publisher=Yale University Press |location=New Haven, Connecticut |isbn=978-0-300-21502-1 |chapter=A Butterfly Bridge for the Bay |pages=87–96 |access-date=10 July 2019}} The Butterfly Wing bridge was first presented to the public in May 1953 before a sold-out audience at the San Francisco Museum of Art.{{cite news |url=https://cdnc.ucr.edu/?a=d&d=MVR19530502.2.18 |title=Wright Terms Northbay Bridge An "Eyesore" and "Anachronism" |date=May 2, 1953 |newspaper=Mill Valley Record |access-date=9 July 2019}} A {{convert|16|ft|abbr=on|adj=on}} long model of the Butterfly Wing bridge was built for the 1953 presentation; it was later displayed locally in shops,{{cite web |url=https://digital.lib.buffalo.edu/items/show/88862 |title=Model of the Frank Lloyd Wright-J.J. Polivka "Butterfly Wing Bridge" on display in the Emporium department store in San Francisco |date=1953 |publisher=J.J. Polivka papers, State University of New York at Buffalo |access-date=11 July 2019}} malls,{{cite news |url=https://www.kqed.org/news/11642644/the-beautiful-bay-bridge-frank-lloyd-wright-never-got-to-build |title=The Beautiful Bay Bridge Frank Lloyd Wright Never Got to Build |author=Myrow, Rachael |date=January 25, 2018 |work=KQED News |access-date=11 July 2019}} and was included in a traveling exhibition before being used as a prop in the 1988 film Die Hard.

Polivka had previously submitted preliminary plans to DPW for a Southern Crossing bridge in February 1947; his initial design featured an immense {{convert|3200|ft|adj=on}} long concrete arch spanning the navigation channel, which was unprecedented in length, size, and material.{{cite magazine |url=https://www.eichlernetwork.com/article/visionaries-wing?page=0,0 |title=Visionaries on the Wing: As the Bay Bridge reopening nears, lost in the hoopla is Frank Lloyd Wright's forsaken 'Butterfly' design—the most beautiful span of all |author=Weinstein, Dave |date=Summer 2013 |magazine=Modern Living Today |publisher=Eichler Network |access-date=11 July 2019}} Polivka is credited with piquing Wright's interest in bridge design; they began their collaboration later in 1947, resulting in the Butterfly Wing bridge proposal for the Southern Crossing.{{cite conference |url=https://www.arct.cam.ac.uk/Downloads/ichs/vol-1-741-758-cleary.pdf |title=Lessons in Tenuity: Frank Lloyd Wright's Bridges |author=Cleary, Richard |date=March–April 2006 |conference=Second International Congress on Construction History |publisher=University of Cambridge |pages=741–758 |access-date=10 July 2019}}{{rp|748}} The Butterfly Wing design was derived from a crossing designed by Wright in 1947 over the Wisconsin River near Spring Green, Wisconsin for the Wisconsin Highway commission.{{cite web |url=http://www.steinerag.com/flw/Artifact%20Pages/Projects.htm#ButFly |title=Frank Lloyd Wright Projects: Butterfly-Wing Bridge |publisher=The Wright Library |access-date=10 July 2019}}

The final design carries six lanes of traffic over twin {{convert|2000|ft|adj=on}} long diverging arches providing {{convert|200|ft}} of vertical clearance above the bay's main ship channel.{{cite web | url=http://www.lib.berkeley.edu/news_events/bridge/up027.html | title=Bridging the Bay: Bridges That Never Were | publisher=University of California, Berkeley Libraries | access-date=August 5, 2012}} Another source claims the pair of main arches were {{convert|1000|ft}} long and afforded {{convert|175|ft}} of vertical clearance.{{rp|750–752}} The concrete "tap-root" piers were hollow to add buoyant support to the structure. The original alignment had a western terminus near Third and Army {{color box|#008|3|#fff|border=silver}} and an eastern terminus on Bay Farm Island {{color box|#fb0|8|#000|border=silver}}.{{cite web |url=http://www.agaarchitects.com/pages/agg_and_fllw/butterfly.html |title="Butterfly Bridge": The Southern Crossing |publisher=Aaron G. Green Associates, Inc. |access-date=11 July 2019}} The design included a hanging park and parking in the middle of the arched section, making the Butterfly Bridge a destination in addition to a crossing.{{cite news |url=https://www.sfchronicle.com/oursf/article/Our-SF-Frank-Lloyd-Wright-had-the-right-idea-6277392.php |title=Frank Lloyd Wright's Butterfly Bridge plan would have transformed San Francisco |author=Hartlaub, Peter |date=May 23, 2015 |newspaper=San Francisco Chronicle |access-date=2 July 2019}} Polivka and Wright's design, using reinforced concrete, was designed to be half the cost of a conventional steel bridge, provide lower maintenance costs, and resist earthquake damage.{{cite magazine |url=https://www.buffalospree.com/buffalospreemagazine/archives/2000_1112/111200architecture.html |title=In Wright's Shadow: The Legacy of Jaroslav Polivka |author=Muskat, Barry |date=November–December 2000 |magazine=Buffalo Spree |access-date=11 July 2019}} However, such proposals never got beyond the drawing board because of cost concerns.{{cite news |url=https://www.sfgate.com/travel/resources/transit/article/Bay-bridge-Southern-Crossing-transit-traffic-BART-13908187.php |title=Why no one has approved a second Bay bridge for 70 years |author=Moffitt, Mike |date=June 12, 2019 |newspaper=San Francisco Chronicle |access-date=9 July 2019}}

The Butterfly Wing bridge design has been revived occasionally since it was first announced; in 1989, the Oakland Museum of California exhibited the bridge drawings and model, and that year, Aaron Green and T. Y. Lin proposed the Wright/Polivka design should be built between San Bruno {{color box|#008|12|#fff|border=silver}} (western terminus at the junction of I-380 and the Bayshore Freeway) and San Lorenzo {{color box|#fb0|11|#000|border=silver}} (terminating into Hwy 238), carrying eight lanes of traffic and BART tracks.{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SBS19890629.1.18 |title=New commuter gimmick — Butterfly Wing: Span designed by Frank Lloyd Wright could ease region congestion |author=Grieve, Tim |agency=McClatchy News Service |date=June 29, 1989 |newspaper=San Bernardino Sun |access-date=9 July 2019}} In 1999, the Butterfly Wing design was again promoted, this time as a candidate design for the eastern span replacement of the San Francisco–Oakland Bay Bridge,{{cite web |url=http://files.mtc.ca.gov/library/BBC/pdf/ACCNO_000713.PDF |title=Butterfly-Wing Bridge |author=Wright, Frank Lloyd |author-link=Frank Lloyd Wright |date=1999 |publisher=Metropolitan Transportation Commission |access-date=10 July 2019}} winning Oakland mayor Jerry Brown's support, although by that time, the design had already missed the deadline for replacement proposals, which had been during a three-day workshop held in 1997.{{cite news |url=https://www.sfgate.com/news/article/Bridge-with-the-Wright-stuff-3094406.php |title=Bridge with the Wright Stuff |author=Hendricks, Tyche |newspaper=San Francisco Examiner |date=March 7, 1999 |access-date=9 July 2019}}

File:1954-southern-crossing-approved.jpg

In 1953, the legislature passed a bill to build the Southern Crossing with the alignment spanning from San Francisco near Third and Army Streets (Potrero Point {{color box|#008|3|#fff|border=silver}})to near Bay Farm Island {{color box|#fb0|8|#000|border=silver}} in Alameda.{{cite web | url=http://www.asce-sf.org/index.php?Itemid=79&id=167&option=com_content&task=view | title=A Proposed "Southern Crossing" for San Francisco Bay | first=Jim | last=Martin | work=American Society of Civil Engineers | access-date=August 5, 2012}} The western approaches would include connections to the Bayshore Freeway at 26th Street; the Southern Crossing would also connect with a proposed future freeway at Army Street and an extended Embarcadero Freeway.{{rp|§ V}} At the eastern end, the southern crossing would connect to the Alameda County road along the bayfront near its intersection with Kilkenny Road.{{rp|§ VI}}{{cite California statute |year=1953 |chapter=1056 |page=2525 |title=An act to repeal Sections 30605, 30606, 30607, and 30608 of the Streets and Highways Code, to amend Section 100.7 thereof, and to add Sections 30605 and 30607 and Article 2 to Chapter 2 of Division 17 of said code, relating to toll crossings of San Francisco Bay, including approaches thereto, and the expenses of maintaining, operating, and insuring such crossings, and providing for studies of an additional crossing. |quote=The authority and the department shall apply promptly to the appropriate officials of the Federal Government for permission to construct a southern crossing having its westerly terminus in the vicinity of Third and Army Streets in the City and County of San Francisco and its easterly terminus on Bay Farm Island, and shall obtain the necessary permits therefor as promptly as feasible.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1953/53Vol1_Chapters.pdf#page=1920 direct URL] The Southern Crossing alignment specified by the legislature had not been previously studied in the 1941 and 1947 reports.{{rp|I-6}}

After the Southern Crossing Bill was passed, at a public hearing held on August 17, 1953, the Navy announced plans to extend its seadrome runways south from NAS Alameda, which would interfere with the planned direct alignment of the Southern Crossing, and the Department of the Army subsequently denied the Southern Crossing application on November 3, 1953.{{rp|I-6}} A revised alignment was designed to route around the restricted area, and the Army granted a construction permit on April 8, 1954,{{rp|I-7}} contingent on the construction to start within five years and complete within ten.{{rp|Append-11}}

In the 1954 Progress Report, the approved design for the Southern Crossing was largely a low-level causeway not to exceed {{convert|40|ft}} in height to avoid seadrome interference, although the eastern approach would provide a vertical clearance of {{convert|15|ft}} to allow the passage of crash boats from NAS Alameda. A tube section would be built across the navigation channel to allow the passage of ships deeper into the Bay. Traffic would be carried in six lanes, divided into two three-lane causeways and three two-lane tubes, and grades would be limited to 3{{frac|2}}%. The total planned length of the 1954 Southern Crossing was {{convert|40730|ft}}.{{cite report |url=https://archive.org/details/progressreportto1954cali |title=A Progress Report to Department of Public Works on a Southern Crossing of San Francisco Bay |author=Raab, N. C. |date=December 1954 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=2 July 2019}}{{rp|IV-1,2}}

According to the 1955 Progress Report, the preliminary plans had been completed and updated cost estimates were available.{{cite report |url=https://archive.org/details/southern-crossing-1955-12/ |title=Report to Department of Public Works on the Southern Crossing of San Francisco Bay |author=Raab, N. C. |date=December 1955 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=5 July 2019}} In March 1956, the 1955 Supplement report was issued covering the legislative amendments made that month changing the San Francisco approaches to the Southern Crossing.{{cite California statute |year=1955 |chapter=304 |page=754 |title=An act to amend Sections 30350, 30652, and 30654 of, and to add Sections 30608, 30654.5, and 30659 to, the Streets and Highways Code, relating to toll bridges and other toll highway crossings, declaring the urgency thereof and providing that this act shall take effect immediately.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1955/55Vol1_55Chapters.pdf#page=327 direct URL]{{cite report |url=https://archive.org/details/progressreportt1955cali_0/ |title=A Supplement to the Report of December 1955 to Department of Public Works on the Southern Crossing of San Francisco Bay, Covering Proposed Approach Amendments to Assembly Bill No. 3249 as Outlined in Assembly Journal for March 23, 1955, at Page 1704 |author=Raab, N. C. |date=March 1956 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=5 July 2019}} (this version has the full text, but omits the figures){{cite report |url=https://archive.org/details/southern-crossing-1956-03/ |title=A Supplement to the Report of December 1955 to Department of Public Works on the Southern Crossing of San Francisco Bay, Covering Proposed Approach Amendments to Assembly Bill No. 3249 as Outlined in Assembly Journal for March 23, 1955, at Page 1704 |author=Raab, N. C. |date=March 1956 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=5 July 2019}} (this version reproduces the figures, but omits Part I of the text)

File:1956 Southern Crossing Fig IV-02.jpg

The Southern Crossing design was updated again in October 1956; the 1956 Progress Report detailed further changes to the San Francisco and Bay Farm Island approaches mandated by legislative action.{{cite California statute |year=1956 |ex=1 |chapter=40 |page=381 |title=An act to add Section 30354.5 to the Streets and Highways Code, relating to toll bridges across San Francisco Bay acquired or constructed pursuant to the California Toll Bridge Authority Act, declaring the urgency thereof, to take effect immediately.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1957/57Vol1_56Chapters.pdf#page=376 Chapter 40, direct URL]{{cite California statute |year=1956 |ex=1 |chapter=67 |page=459 |title=An act to amend Sections 30654 and 30657 of the Streets and Highways Code, relating to toll bridges and other toll highway crossings.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1957/57Vol1_56Chapters.pdf#page=454 Chapter 67, direct URL]{{cite report |url=https://archive.org/details/progressreportto1956cali/ |title=A Report to the Department of Public Works on the Southern Crossing of San Francisco Bay |author=Raab, N. C. |date=October 1956 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=5 July 2019}} By 1956, the Southern Crossing was ready to post requests for bidding; because there was "considerable opposition to raising tolls on the Bay Bridge" from their current {{USD|0.25|1956|round=2}}, the cost of the Southern Crossing meant the project would have to be built in stages.{{rp|I-3}} The overall length of the Southern Crossing was reduced slightly to {{convert|39910|ft}} with the revised approaches, but retained the same basic structure: two three-lane roadways carried on mole and viaducts, with a three-tube (each with two unidirectional lanes) section crossing the navigation channel.{{rp|II-2}} In San Francisco, the northern approach would connect with the Embarcadero Freeway; the southern approach would connect with the Southern Freeway, and the direct connection with the Bayshore Freeway was dropped. Both approaches would be double-decked, with three unidirectional lanes per deck.{{rp|II-4}} On Bay Farm Island, the Southern Crossing would split into two separate approaches at the Bay Farm Island Bridge; the two would then would connect with the Eastshore Freeway and the Posey and Webster Street tubes.{{rp|II-5}} In addition, the 1956 Progress Report considered the effect of the Southern Crossing on traffic over the San Mateo–Hayward Bridge (acquired by the State of California in September 1951) as well as the planned Transbay Tube.{{rp|§ VIII}}

To explore the financial feasibility further, DPW commissioned a study from Smith Barney & Co., which concluded "the Complete Southern Crossing is not feasible as presently authorized at a basic toll rate of 25 cents for both the Bay Bridge and the Southern Crossing"; the California Toll Bridge Authority then directed Bay Toll Crossings to develop a Minimum Southern Crossing plan.{{cite report |url=https://archive.org/details/progressreportto1956cali/ |title=A Report to the Department of Public Works on the Southern Crossing of San Francisco Bay |author=Raab, N. C. |date=December 1957 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=5 July 2019}}{{rp|I-1,2}} One key statute passed in the 1957 session imposed a July 1, 1958 deadline; if funding was not finalized for the Southern Crossing by then, the project would be dissolved.{{cite California statute |year=1957 |chapter=2316 |page=4030 |title=An act to add Sections 30609 and 30660 to the Streets and Highways Code, relating to crossings of San Francisco Bay, declaring the urgency thereof, and providing that this act shall take effect immediately.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1957/57Vol2_57Chapters.pdf#page=1295 Chapter 2316, direct URL] Another authorized funds for the construction of the Webster Street Tube without tying it to the larger Southern Crossing project.{{cite California statute |year=1957 |chapter=866 |page=2079 |title=An act to amend Section 30657 of the Streets and Highways Code, relating to San Francisco Bay crossings.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1957/57Vol1_57Chapters.pdf#page=1536 Chapter 866, direct URL] Under the Minimum Southern Crossing plan of 1957, the same general alignment and design was retained, but the approaches were pruned back to a single interchange near Third and Army in San Francisco and a connection to the Bay Farm Island Bridge in the East Bay.{{rp|II-1,2}}

In May 1958, the Southern Crossing project was defunded and abandoned;{{cite California statute |year=1958 |chapter=3 |ex=2 |page=584 |title=An act making funds available for surveys and studies of an additional San Francisco Bay crossing.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1959/59Vol1_58Chapters.pdf#page=5778 direct URL] plans made to expand the capacity of existing crossings (plans completed in March 1957 to remove the Key System tracks on the lower deck of the Bay Bridge; additionally, plans completed in October 1958 to double the capacity of the San Mateo Bridge) meant a second crossing was no longer needed. In addition, by this time, plans for the Transbay Tube for public transit service across the Bay had been sufficiently developed to forecast relief for Bay Bridge traffic.{{cite report |url=https://archive.org/details/progressreportto1959cali |title=A Report to the Department of Public Works on the Studies of Southern Crossings of San Francisco Bay |author=Raab, N. C. |date=January 1959 |publisher=Division of San Francisco Bay Toll Crossings, Department of Public Works, State of California |access-date=5 July 2019}}{{rp|§ II}}

File:1966 Southern Crossings of San Francisco Bay.jpg

Yet another alternative alignment, proposed in the November 1962 Trans-bay Traffic Study, would connect India Basin {{color box|#008|9|#fff|border=silver}} to both Alameda {{color box|#fb0|7|#000|border=silver}} and Bay Farm Island {{color box|#fb0|8|#000|border=silver}}; the bridge would run to a mid-Bay junction off the southern shore of Alameda and then fork north and east, respectively. The 1962 study also included a more southern alternative alignment between Sierra Point {{color box|#008|10|#fff|border=silver}} and Roberts Landing {{color box|#fb0|11|#000|border=silver}} in San Lorenzo, the first Southern Crossing proposal to include a terminus in San Mateo County. Subsequent public hearings, held in 1964 and 1965, showed strong popular support for both of the two proposed routes, with home geography dictating which route was favored,{{cite report |url=https://archive.org/details/southern-crossing-1966 |title=Southern Crossing Of San Francisco Bay: India Basin-Alameda & Sierra Point-Roberts Landing Alignment Studies |date=February 1966 |publisher=Division of Bay Toll Crossings, California Department of Public Works |access-date=1 July 2019}}{{rp|4–5}} and in 1965, the legislature authorized a study to compare the two alternatives as well as ferry service.{{cite California statute |year=1965 |chapter=970 |page=2588 |title=An act providing for preliminary studies of a toll crossing of, or the use of surface craft for the crossing of, San Francisco Bay, making an appropriation therefor, and declaring the urgency thereof, to take effect immediately.}} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1965/65Vol2.PDF#page=776 direct URL] The results of that study were published in the 1966 Southern Crossing of San Francisco Bay report.

For the India Basin–Alameda–Bay Farm Island alternative, the main navigation channel off Hunters Point would be spanned by either a high-level bridge (providing at least {{convert|220|ft|abbr=on}} of vertical clearance) or a subsurface tube (allowing at least {{convert|50|ft|abbr=on}} of draft). On the western end, the approach would connect to a proposed Hunters Point Freeway which would run north-south to the east of the existing Bayshore Freeway. The eastern approach would split into two at the toll plaza, located approximately {{convert|1|mile}} offshore from Alameda; the northerly leg would continue to a new set of tubes parallel to the existing Posey and Webster Street tubes, while the easterly leg would continue to Davis Street in San Leandro.{{rp|14–29}} The estimated cost of this alignment would range between $300.8 million (bridge) to $397.1 million (tunnel), depending on the option chosen to cross the navigation channel.{{rp|36–37}}

The Sierra Point–Roberts Landing alternative was first proposed in 1959; the total length of approximately {{convert|12.5|mi|abbr=on}} would be low-level trestle or earthen barrier, with a high-level bridge over the navigation channel, similar to the second San Mateo–Hayward Bridge. The earthen barrier option was a variant of the Reber Plan, calling for a series of locks to preserve a navigation channel south, but otherwise allowing residential development on Bay fill south of the barrier.{{rp|40–55}} The total estimated cost of this alignment ranged between $209.7 million (trestle) to $352.6 million (barrier).{{rp|60–61}}

Of the two alignments, the India Basin–Alameda–Bay Farm Island option was expected to have the greatest relief for Bay Bridge traffic and was recommended in the 1966 study report. Under the contemporary rules, the amount of money diverted from toll revenues to fund BART meant that construction of either alternative would be delayed to 1968; if the diversion was increased from $133 million to $178 million, however, the Southern Crossing would be delayed or potentially unfeasible. The earthen barrier option of the Sierra Point–Roberts Landing alignment was ruled out as the economic benefits would not justify the additional cost.{{rp|104–106}}

File:1971 Southern Crossing alignment.jpg was later truncated and replaced with Interstate 880 and Interstate 580.]]

The Hunters Point/India Basin–Alameda–Bay Farm Island alignment was ultimately selected in April 1966{{rp|21}} with a cable-stayed girder bridge over the main channel using an orthotropic deck. The design of the channel span was directed by the noted local architect William Stephen Allen, designed to harmonize with the neighboring Bay and San Mateo bridges.{{rp|13}} The Bay Conservation and Development Commission granted permits for construction of the Southern Crossing on November 6, 1969.{{rp|21}}

Opposition to the Southern Crossing was led by the Sierra Club and notable local politicians, including state senator George Moscone; Assemblymembers Willie Brown, John Burton, John Foran, and Leo McCarthy; and Supervisors Dianne Feinstein, Terry Francois, Robert E. Gonzalez, Robert H. Mendelsohn, and Ron Pelosi.{{cite news |url=https://archive.org/details/potreroview21unse |title=Southern crossing protest |date=January 1, 1971 |volume=2 |number=1 |newspaper=The Potrero View |access-date=8 July 2019}} In San Francisco, Francois and Gonzalez argued the estimated $500 million cost of the Southern Crossing project would be better spent on rapid transit, and Mendelsohn and Pelosi introduced a resolution to require the project to evaluate its impact on BART.{{cite news |url=https://archive.org/details/potreroview22unse |title=Southern Crossing meets growing opposition |date=February 1, 1971 |volume=2 |number=2 |newspaper=The Potrero View |access-date=8 July 2019}} Support for the Southern Crossing was largely from legislators representing districts outside the Bay Area; local polls from early 1972 showed that nearly two-thirds of Bay Area residents opposed the Southern Crossing.{{cite news |url=https://archive.org/details/potreroview36unse |title=Southern span yes or no? |date=June 1, 1972 |volume=3 |number=6 |newspaper=The Potrero View |access-date=8 July 2019}}

The scheduled start of construction was delayed until late 1971, and the anticipated completion date was 1975. Because of its potential to siphon riders (and revenue) away from the nascent BART system, the California State Assembly ordered the Toll Bridge Authority to reconsider the Southern Crossing in 1970.{{Cite California statute | year=1970 | chapter=211 | page=3811 | title=Assembly Concurrent Resolution No. 26—Relative to the southern crossing | res=ACR 26 }} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1970/70Vol2_Chapters.pdf#page=1799 direct URL] In February 1971, the Toll Bridge Authority concluded in a report published after holding two public meetings in San Francisco and Oakland that "It is in the public interest to begin construction on this needed facility [the Southern Crossing] as soon as possible."{{cite report |url=https://archive.org/details/southern-crossing-comprehensive-review/ |title=Southern Crossing of San Francisco Bay: Comprehensive Review Requested by Assembly Concurrent Resolution No. 26, Chapter 211, Statutes 1970 |date=February 1971 |author=Van Camp, Brian R. |publisher=California Toll Bridge Authority of the State of California |access-date=8 July 2019}} At the Oakland meeting, held the preceding December, chief engineer E. R. "Mike" Foley of the Toll Bridge Authority argued the Southern Crossing was needed to support cargo traffic and to relieve congestion on the Bay Bridge, but local politicians opposing the new bridge cited pollution concerns and the possibility of increased traffic jams due to induced demand.{{cite news |url=https://cdnc.ucr.edu/?a=d&d=SCS19701215.1.12 |title=Proponents Claim Southern Crossing Would Aid BART |agency=AP |date=December 15, 1970 |newspaper=Santa Cruz Sentinel |access-date=8 July 2019}}

The 1971 report concluded that BART revenues would be minimally affected, as the Southern Crossing would provide access to southern San Francisco and northern San Mateo County, while BART would serve downtown San Francisco instead.{{rp|7}} At the time, the Bay Bridge was operating at well over its designed capacity, serving 165,000 vehicles per day, on average. BART was anticipated to divert 10% of existing traffic to provide some relief, but by 1980, it was projected the Bay Bridge would see 190,000 vehicles per day while BART would move 143,000 trans-Bay commuters daily. If the Southern Crossing had been built, it was projected that in 1980, Bay Bridge traffic would be reduced to 148,000 vehicles per day, the Transbay Tube would serve 138,000 daily commuters, and the Southern Crossing would be operating at 105,000 vehicles per day.{{rp|4–5}}

File:Southern Crossing stub ramp from the west, April 2021.jpg on the Interstate 280 viaduct in San Francisco at Galvez Ave., originally intended as part of an interchange with the Southern Crossing]]

In March 1971, Assemblymember Robert W. Crown (D-Alameda) sponsored AB 151, which would give the final decision to proceed with the construction to the legislature, taking that choice away from Bay Toll Crossings.{{cite news |url=https://archive.org/details/potreroview23unse |title=Bridge Authority faces challenge |date=March 1, 1971 |volume=2 |number=3 |newspaper=The Potrero View |access-date=8 July 2019}} Although it passed both houses with overwhelming majorities, AB 151 was vetoed by Governor Ronald Reagan,{{cite web |url=https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1971/71Vol3_Summary.pdf#page=3773 |title=Summary Digest of Statutes Enacted and Resolutions Adopted Including Proposed Constitutional Amendments and 1969–1971 Statutory Record |date=1971 |page=317 |publisher=California Legislature |access-date=8 July 2019}} who stated the citizens of the Bay Area should be allowed to vote for the approval of the Southern Crossing directly.{{cite news |url=https://cdnc.ucr.edu/?a=d&d=DS19710403.2.33 |title=Bridge Bill Vetoed By Governor |agency=UPI |date=April 3, 1971 |newspaper=Desert Sun |access-date=8 July 2019}} The Assembly was unable to override the veto,{{cite news |url=https://cdnc.ucr.edu/?a=d&d=DS19710423.2.23 |title=Reagan Winner: Democrats Unable To Override Veto |agency=UPI |date=April 23, 1971 |newspaper=Desert Sun |access-date=8 July 2019}} and two regional measures were put on the ballot for six Bay Area counties in the June 6, 1972 election: one that would give the final approval for the Southern Crossing to the legislature,{{cite news |url=https://cdnc.ucr.edu/?a=d&d=DS19720606.2.24 |title=73 Per Cent Vote Turnout Due For State |agency=UPI |date=June 6, 1972 |newspaper=Desert Sun |access-date=8 July 2019}} which voters approved,{{cite news |url=https://cdnc.ucr.edu/?a=d&d=DS19720607.2.2 |title=Proposition Nine Loses By 2-1; All Others Pass |agency=UPI |date=June 7, 1972 |newspaper=Desert Sun |access-date=8 July 2019}} and another (Proposition A) which would issue bonds to fund the Southern Crossing, which was defeated.{{cite news | url=http://www.sfgate.com/bayarea/matier-ross/article/Feinstein-Pushes-for-Southern-Crossing-Letter-2783076.php | title=Feinstein Pushes for Southern Crossing |author1=Matier, Phillip |author2=Ross, Andrew | date=January 19, 2000 |newspaper=San Francisco Chronicle | access-date=May 5, 2017}}{{cite web |url=http://www.lib.berkeley.edu/news_events/bridge/up004.html |title=No on A |publisher=Sierra Club |date=1972 |access-date=11 July 2019}}

File:2002 San Francisco Bay Crossings Study Final Report - Fig 17 (Mid-Bay Bridge).png

In 1989, State Senator Quentin L. Kopp introduced Senate Concurrent Resolution No. 20, which funded a study to analyze the need for another crossing option (whether tunnel, bridge, or ferry) between Alameda County and San Francisco or San Mateo County.{{Cite California statute | year=1989 | chapter=168 | page=7037 | title=Senate Concurrent Resolution No. 20—Relative to a San Francisco Bay crossing study | res=SCR 20 }} [https://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1989/89Vol4_DigestChapters.pdf#page=634 direct URL] The resulting Bay Crossings Study was published by the Metropolitan Transportation Commission (MTC) in 1991 and the scope was not limited to an automobile bridge; the eleven alternatives studied were:{{cite web |url=http://www.mtc.ca.gov/library/bay_crossing/bay_crossing2.htm |title=Bay Crossings Study |date=1991 |publisher=Metropolitan Transportation Commission |archive-date=September 28, 2006 |archive-url=https://web.archive.org/web/20060928155407/http://www.mtc.ca.gov/library/bay_crossing/bay_crossing2.htm |url-status=dead}}

1. High-Speed Ferry and Operational Upgrade
2. Southern Crossing Bridge
3. Southern Crossing tunnel
4. Interstate 380 to I-238 bridge (with BART)
5. Interstate 380 to I-238 tunnel (with BART)
6. BART SFO/OAK airport connection
7. BART Alameda to Candlestick connection
8. New BART Transbay Tube
9. Airport people-mover connection
10. Railroad Airport connection
11. Intercity rail connection

Of these, the 1991 Bay Crossings Study evaluated five: alternatives 1, 4, 6, 8, and 11. The proposed alignment for a new Mid-Bay Bridge (Alternative 4) ran between San Bruno {{color box|#008|12|#fff|border=silver}} and San Leandro {{color box|#fb0|11|#000|border=silver}}; two variants of Alternative 4 were studied in 1991, one with four lanes and another with eight lanes and BART tracks. The narrow four-lane bridge was estimated to cost $2 billion.{{cite news |url=https://www.sfgate.com/bayarea/article/Southern-Crossing-Boulevard-of-Broken-Dreams-2782496.php |title=Southern Crossing: Boulevard of Broken Dreams |author=Nolte, Carl |date=January 20, 2000 |newspaper=San Francisco Chronicle |access-date=11 July 2019}} The eight-lane bridge was estimated to cost the most out of all the alternatives studied ($4 B), but would carry the greatest number of trips, providing the most relief to Bay Bridge traffic.

This Southern Crossing initiative eventually died after facing opposition from environmental groups.

U.S. Senator Dianne Feinstein revived the Southern Crossing proposal in 2000, writing a letter to California Governor Gray Davis that a study of an alternative bay crossing "must be undertaken promptly", citing projections of growing traffic congestion. After two years, MTC published the 2002 San Francisco Bay Crossings Study, an update to the prior 1991 study;{{cite report |url=http://files.mtc.ca.gov/library/BBC/pdf/ACCNO_000072.PDF |title=San Francisco Bay Crossings Study |date=July 2002 |publisher=Metropolitan Transportation Commission |access-date=12 July 2019}} in it, MTC concluded that a Mid-Bay Bridge between Interstate 238 in Hayward and Interstate 380 in San Bruno would cost up to {{US$|8.2{{nbsp}}billion|link=yes}} to build.{{rp|42}} Other alternatives that were studied in this period included a second Transbay Tube, widening the San Mateo–Hayward Bridge to eight lanes, and Dumbarton Rail Corridor service; of these, the Mid-Bay Bridge proved to be the most polarizing, the second Tube was the costliest, and Dumbarton Rail was called "one of the least expensive and most cost-effective of the transbay improvements studied."{{rp|2}} Several alternatives were screened out during preliminary evaluations as unfeasible, including a road and rail bridge between I-238 and Candlestick Point, a Mid-Bay BART tube, and a SFO—OAK airport rail shuttle.{{rp|24}}

The idea was then shelved until 2010 when the Bay Area Toll Authority voted to spend up to {{US$|400,000}} to update the 2002 study.{{cite news | url=http://www.pleasantonweekly.com/news/show_story.php?id=5506 | title=New Bay Bridge from San Lorenzo? 'Southern Crossing' span back on planners' study plate | work=Pleasanton Weekly News | date=November 10, 2010 | access-date=August 5, 2012}} The resulting San Francisco Bay Crossings Study Update (2012) concluded that due to increased costs no new trans-Bay crossings were feasible. The Mid-Bay Bridge was estimated to cost $12.4 billion, improvements to the San Mateo–Hayward and Dumbarton bridges were estimated at $2.9 billion each, and a second BART tube would cost from $8.2 to $11.2 billion, depending on the alignment.{{cite report |url=https://mtc.ca.gov/sites/default/files/BC_Study_Update_May_2012.pdf |title=San Francisco Bay Crossings Study Update |date=May 2012 |author=AECOM |publisher=Metropolitan Transportation Commission |access-date=12 July 2019}}{{rp|2–4}}

In December 2017, in a letter to the MTC, Feinstein, along with Congressman Mark DeSaulnier, called yet again for a new span across the Bay.{{cite news

| author = Daniel Borenstein

| title = Feinstein calls for new bridge across the bay

| url = http://www.mercurynews.com/2017/12/07/borenstein-feinstein-calls-for-new-bridge-across-the-bay/

| work = The Mercury News

| date = 2017-12-07

| access-date = 2017-12-08

}}

{{Reflist}}

{{Commons category}}

{{Portal|Transport|Engineering|San Francisco Bay Area}}

• {{cite web |url=https://fineart.ha.com/itm/fine-art-work-on-paper/jaroslav-polivka-czech-1886-1960-blueprints-for-frank-lloyd-wright-s-san-francisco-bay-bridge-ten-works-/a/5355-67060.s |title=Heritage Auction #5355, Lot #6060: Blueprints for Frank Lloyd Wright's San Francisco Bay Bridge, dated 1949 |date=April 2018 |author=Polivka, Jaroslav |publisher=Heritage Auctions |access-date=11 July 2019}}
• {{cite web |url=https://www.britishpathe.com/video/model-of-the-butterfly-bridge |title=Model Of The Butterfly Bridge |date=1953 |publisher=British Pathé |access-date=11 July 2019}}
• {{cite web |url=https://99percentinvisible.org/article/butterfly-bridge-wrights-unbuilt-bay-crossing-cars-pedestrians/ |title=The Butterfly Bridge: Wright's Unbuilt Bay Crossing for Cars & Pedestrians |author=Kohlstedt, Kurt |date=16 March 2018 |publisher=99% Invisible |access-date=11 July 2019}}

{{Bay Area tunnels}}

{{SF Bay Area|state=collapsed}}

{{Authority control}}

Category:Transportation in the San Francisco Bay Area

Category:Proposed bridges in the United States

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