Southern Crossing (California)

Southern CrossingSan Francisco Bay Southern CrossingSouthern Crossing bridge
The Southern Crossing is a proposed highway structure that would span San Francisco Bay in California, somewhere south of the San Francisco–Oakland Bay Bridge and north of the San Mateo–Hayward Bridge.wikipedia
85 Related Articles

Transbay Tube

new separate Transbay Tubesecond Transbay Tube
A similar underwater route, with terminii 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.
A competing bridge-and-tunnel proposal was advanced in July 1921 by J. Vipond Davies and Ralph Modjeski, closer to the alignment of a proposed Southern Crossing, between Mission Rock and Potrero Point in San Francisco due east to Alameda.

Interstate 980

I-980980
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.
The freeway was planned as the eastern approach to the San Francisco Bay Southern Crossing.

Cesar Chavez Street

Army StreetEast César Chávez Street
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 ) to Alameda was preferred.
The widening of Army Street was made as part of the development of the never constructed Southern Crossing from San Francisco to the East Bay.

Jaroslav Josef Polívka

Jaroslav Joseph PolivkaJaroslav Josef PolivkaJ. Havlicek
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.
Their other well-known design proposal was the reinforced concrete Butterfly Bridge (proposed at a world record span of 1000-ft )at the Southern Crossing of the San Francisco Bay (1949–52).

San Francisco Bay

BaySan FranciscoSan Francisco Harbor
The Southern Crossing is a proposed highway structure that would span San Francisco Bay in California, somewhere south of the San Francisco–Oakland Bay Bridge and north of the San Mateo–Hayward Bridge.

California

CAState of CaliforniaCalifornia, USA
The Southern Crossing is a proposed highway structure that would span San Francisco Bay in California, somewhere south of the San Francisco–Oakland Bay Bridge and north of the San Mateo–Hayward Bridge.

San Francisco–Oakland Bay Bridge

Bay BridgeSan Francisco-Oakland Bay BridgeSan Francisco Bay Bridge
The Southern Crossing is a proposed highway structure that would span San Francisco Bay in California, somewhere south of the San Francisco–Oakland Bay Bridge and north of the San Mateo–Hayward Bridge.

San Mateo–Hayward Bridge

San Mateo BridgeSan Mateo-Hayward BridgeSan Francisco Bay Toll-Bridge
The Southern Crossing is a proposed highway structure that would span San Francisco Bay in California, somewhere south of the San Francisco–Oakland Bay Bridge and north of the San Mateo–Hayward Bridge.

Yerba Buena Tunnel

a tunneltunneldouble-deck tunnel
After the Bay Bridge crossing opened in 1936, connecting Rincon Hill in San Francisco with the Key Mole 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.

Yerba Buena Island

Goat IslandYerba BuenaYerba Buena Training Station
After the Bay Bridge crossing opened in 1936, connecting Rincon Hill in San Francisco with the Key Mole 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.

Hunters Point Naval Shipyard

San Francisco Naval ShipyardHunter's Point Naval ShipyardHunters Point
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.

Oakland, California

OaklandOakland, CACity of Oakland
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.

California Department of Transportation

CaltransCalifornia Division of HighwaysCalifornia Department of Transportation (Caltrans)
12 from the contemporaneous California Department of Public Works (DPW) study.

Charles H. Purcell

C.H. Purcell
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.

Reber Plan

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 2000 ft wide, reclaiming 180000 acre of land from San Francisco Bay and eliminating the need for another bridge.

Naval Air Station Alameda

NAS AlamedaAlameda Naval Air StationAlameda
The alternative western terminus at Telegraph Hill was rejected on the basis of existing traffic patterns and freeway connections, and the alternative eastern terminus on the S.P. or Oakland Mole 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.

Western Pacific Railroad

Western PacificWestern Pacific RailwayOakland Subdivision
The 1947 study also determined the feasibility of extending existing railroad terminii 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.

Atchison, Topeka and Santa Fe Railway

Santa Fe RailroadAtchison, Topeka and Santa Fe RailroadSanta Fe
The 1947 study also determined the feasibility of extending existing railroad terminii 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.

Southern Pacific Transportation Company

Southern Pacific RailroadSouthern PacificSouthern Pacific Company
The 1947 study also determined the feasibility of extending existing railroad terminii 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.

Dumbarton Rail Bridge

Dumbarton CutoffDumbarton Cut-offDumbarton
The 1947 study also determined the feasibility of extending existing railroad terminii 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.

Market Street Subway

subway under Market Streetdowntown stationsmain tunneled corridor
A similar underwater route, with terminii 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.

Bay Area Rapid Transit

BARTBay Area Rapid Transit (BART)Bay Area Rapid Transit System
A similar underwater route, with terminii 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.

Suspension bridge

suspensionsuspension bridgessuspension footbridge
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 9600 ft long overall, composed of a 4800 ft main span flanked by two 2400 ft side spans.

Golden Gate Bridge

Golden GateDoyle DriveDoyle Drive Replacement Project
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 9600 ft long overall, composed of a 4800 ft main span flanked by two 2400 ft side spans.

Posey and Webster Street tubes

Posey TubeWebsterWebster Tube
Both 10/10A and 12 included the cost of an additional tube to augment the existing Posey tube from Alameda to Oakland, which was eventually constructed as the Webster Street tube in 1968.