San Francisco–Oakland Bay Bridge

The San Francisco–Oakland Bay Bridge is a series of bridges across San Francisco Bay in the U.S. state of California. It is part of Interstate 80 in California.

San Francisco–Oakland Bay Bridge
The western section of the San Francisco–Oakland Bay Bridge
Coordinates	37°49′5″N 122°20′48″W
Carries	10 lanes of I-80 throughout, and pedestrians and bicycles east of Yerba Buena Island (YBI)
Crosses	San Francisco Bay via YBI
Locale	San Francisco and Oakland, California, United States
Owner	State of California
Maintained by	California Department of Transportation and the Bay Area Toll Authority
ID number	34 0003 (West) 34 0004 (YBI Tunnel) 33 0025 (East)[1]
Characteristics
Design	Double-decked suspension spans (two, connected by center anchorage), tunnel, cast-in-place concrete transition span, self-anchored suspension span, precast segmental concrete viaduct
Material	Steel, concrete
Total length	West: 10,304 ft (3,141 m) East span: 10,176 ft (3,102 m) Total: 4.46 miles (7.18 km) excluding approaches
Width	West: 5 traffic lanes totaling 57.5 ft (17.5 m) East: 10 traffic lanes totaling 258.33 ft (78.74 m)
Height	West: 526 ft (160 m)[2]
Longest span	West: two main spans 2,310 ft (704 m) East: one main span 1,400 ft (430 m)
Clearance above	Westbound: 14 feet (4.3 m), with additional clearance in some lanes Eastbound: 14.67 feet (4.47 m)
Clearance below	West: 220 feet (67 m) East: 136 feet (41 m)
History
Designer	Charles H. Purcell
Construction start	July 8, 1933
Opened	November 12, 1936; 88 years ago (1936-11-12)
Statistics
Daily traffic	260,000[3][4]
Toll	Cars (east span, westbound only) $8.00 $4.00 (carpool)
U.S. National Register of Historic Places
Designated	August 13, 2001
Reference no.	00000525[1][5]
Location

It has two spans over water. The western span is a suspension bridge. The eastern span is a self-anchored suspension bridge.^[6] The eastern span used to be a cantilever bridge but it was removed once the new bridge opened. The cantilever span was destroyed in the 1989 Loma Prieta Earthquake, which is one of the reasons why the Eastern span was replaced.

The western span is a double suspension bridge with two decks. Westbound traffic is carried on the upper deck and eastbound on the lower deck. The new east span is a single deck with the eastbound and westbound lanes on each side. It is the world's widest bridge.^[7]