Golden Gate Bridge 75th anniversary May 27, 2012

http://goldengatebridge75.org/

75 years ago on this date, May 27, 1937 was “Pedestrian Day” for the Golden Gate Bridge. Golden Gate Bridge spans the San Francisco Bay from the edge of the city of San Francisco at the Presidio on the southern peninsula to the headlands of Marin County on the north end across the strait.

In 1937 the bridge was open for 12 hours to pedestrian activity. An estimated 200,000 people walked on the bridge that day. Vehicular traffic took over the Golden Gate Bridge the next day, May 28, 1937 for the next 50 years.

“Bridgewalk 1987” saw an even larger crowd of 300,000 pedestrians fill the entire roadway span of the Golden Gate Bridge over a four hour access period from 6am to 10am Sunday, May 24, 1987 for the 50th anniversary of the bridge. The curved span of the bridge flattened out with the weight of all the people. Another 500,000 people were estimated to be on either side of the bridge and not actually on the main bridge span.

My San Francisco born and raised father was 5 years old for Pedestrian Day 1937. He does not recall being at Pedestrian Day 1937. He did make it onto the Golden Gate Bridge for Bridgewalk ‘87.

Engineers afterward determined the 1987 stress on the bridge did not compromise the structure, but there is no bridge walk repeat for the 75th anniversary today.

Link to photo: Bridgewalk ‘87 aerial photo – Martin Klimek.

Key Facts for Golden Gate Bridge:

• Total length of bridge including approaches = 1.7 miles; 8,981 ft.
• Length of suspension span including main span and side spans = 1.2 miles; 6,450 ft.
• Length of suspension span  excluding side spans = 4,200 ft.
• Width of bridge = 90 ft.
• Width of sidewalk = 10 ft.
• Clearance above high water = 220 ft.
• Deepest foundation below mean low water = 110 ft.
• Height of towers above water = 746 ft.
• Height of towers above roadway = 500 ft.
• Total weight of bridge = 887,000 tons.
• Diameter of main cables = 36.375 inches.
• Number of wires in each cable = 27,572.
• Total length of wire used = 80,000 miles.
• Annual vehicle crossings 39.3 million (2008)
• Toll revenue = $85.4 million (2008)
• Total toll revenue since May 28, 1937 = $1,361,221,357 billion as of Feb 28, 2009.
• Construction cost = $35 million (1937). Golden Gate Bridge bonds paid off in 1971 after $39 million in interest for a $74 million total bridge cost.

The west or open ocean side of the bridge is bicycle traffic and east side or Bay and downtown city view is pedestrian traffic.

Toll Rate History:

• May 1937 = 50 cents each way.
• July 1950 = 40 cents each way.
• February 1955 = 30 cents each way.
• October 1955 = 25 cents each way.
• October 1968 = 50 cents southbound into San Francisco; free northbound.
• March 1974 = 75 cents southbound into San Francisco; free northbound.
• November 1977 = $1.00 southbound toll; free northbound.
• March 1981 = $1.25 southbound toll; free northbound.
• December 1981 = $2.00 southbound toll Fridays and Saturdays; $1.00 other days; free northbound.
• January 1989 = $2.00 southbound; free northbound.
• July 1991 = $3.00 southbound; free northbound.
• September 2002 = $5.00 southbound; free northbound.
• September 2008 = $6.00 southbound; free northbound.

Key Dates for Golden Gate Bridge:

June 28, 1921 Joseph Baermann Strauss submitted sketches to San Francisco City Engineer Michael M. O’Shaughnessy for a cantilever-suspension hybrid bridge crossing the San Francisco strait. Cost estimate $17 million.

November 1925 – Strauss had arranged for Charles A. Ellis, VP of Strauss Engineering Corporation in charge of bridge design and construction supervision, to enlist Leon S. Moisseiff, designer of New York’s Manhattan Bridge, as a member serving on the Board of Consultants for the Golden Gate bridge project.

Moisseiff submitted his Report on Comparative Design of a Stiffened Suspension Bridge over the Golden Gate Strait at San Francisco, Cal.

December 4, 1928 Golden Gate Bridge and Highway District created as the representative of six member California counties San Francisco, Marin, Sonoma, Del Norte, Napa and Mendocino and incorporated by the California State Legislature as the sole entity responsible for the final design, construction and financing of a bridge. The Board of Directors for this entity included engineer Joseph Strauss.

August 27, 1929 Moiseiff’s Suspension Bridge design is the final bridge design adopted by the Board.

August 11, 1930 The War Department had jurisdiction over all harbor construction in San Francisco Bay affecting shipping traffic or military logistics. War Department issues final permit for construction of a 4,200-foot main span with a vertical clearance of 220 feet at mid-span.

August 27, 1930 Strauss submits final plans to the Board.

November 4, 1930 Voters in six counties vote in polls to finance $35 million bond to finance bridge construction. The bridge issue passed. 145,057 voted for it and 46,954 voted against the project.

December 5, 1931 Ellis is fired by J. Strauss after ten years of service. The man largely responsible for creating the Golden Gate Bridge design received no formal credit. He joined the engineering faculty at Purdue University.

Jan 5, 1933 Construction of Golden Gate Bridge began.

Feb 26, 1933 Official groundbreaking ceremony for Golden Gate Bridge.

May 27, 1937 Pedestrian Day Golden Gate Bridge.

May 28, 1937 Golden Gate Bridge opened 12 noon to vehicular traffic.

July 1, 1971 Original bonds for Golden Gate Bridge retired. $35 million in principal and $39 million in interest funded entirely from Golden Gate Bridge tolls.

February 22, 1985  The one billionth car crossed Golden Gate Bridge.

May 24, 1987 50th Anniversary Bridgewalk.

2012 Golden Gate Bridge receives 5 million visitors annually.

May 27, 2012 75th Anniversary Celebration along San Francisco waterfront.

Golden Gate Bridge Seismic Retrofit Design and Construction Project

The Golden Gate Bridge has only been closed three times for weather since it opened in 1937. In the wake of the 1989 Loma Prieta 7.1 earthquake which did no damage to the Golden Gate Bridge, a $16 million study determined a seismic retrofit of the Golden Gate Bridge to prevent a catastrophic collapse in a strong earthquake would be more cost effective than building a new bridge. Phase 1 and 2 of this seismic retrofit were completed from 1997 to 2008. Phase 3 is the main suspension bridge portion still in progress. The overall retrofit is expected to be around $700 million; more than 20x the original bridge construction cost.

Information for this article came from Highlights, Facts & Figures – Golden Gate Bridge, Highway and Transportation District July 2009.

The photos used in this post are my own. I know I have better shots of the bridge, but unable to locate many photos today.

Golden Gate 75 has a page of photos with beautiful shots of the Golden Gtae Bridge and some historical shots too.