1989 Loma Prieta Earthquake - Effects On Transportation

Effects On Transportation

Immediately following the earthquake, San Francisco Bay Area airports closed to conduct visual inspection and damage assessment procedures. San Jose International Airport, Oakland International Airport and San Francisco International Airport all opened the next morning. Massive cracks in Oakland's runway and taxiway reduced the usable length to two-thirds normal, and damage to the dike required quick remediation to avoid flooding the runway with water from the bay. Oakland Airport repair costs were assessed at $30 million.

San Francisco Municipal Railway (Muni) lost all power to electric transit systems when the quake hit, but otherwise suffered little damage and no injuries to operators or riders. Cable cars and electric trains and buses were stalled in place—half of Muni's transport capability was lost for 12 hours. Muni relied on diesel buses to continue abbreviated service until electric power was restored later that night, and electric units could be inspected and readied for service on the morning of October 18. After 78 hours, 96 percent of Muni services were back in operation, including the cable cars.

The earthquake changed the Bay Area's automobile transportation landscape. Not only did the quake force seismic retrofitting of all San Francisco Bay Area bridges, it caused enough damage that some parts of the region's freeway system had to be demolished. Damage to the region's transportation system was estimated at $1.8 billion.

• San Francisco – Oakland Bay Bridge, Interstate 80: The Bay Bridge was repaired and reopened to traffic in a month. However, the earthquake made it clear that the Bay Bridge, like many of California's toll bridges, required major repair or replacement for long-term viability and safety. Construction on a replacement for the eastern span began on January 29, 2002. The project is expected to be completed by 2013.
• Cypress Street Viaduct/Nimitz Freeway, Interstate 880: The double-decked Cypress Street Viaduct, Interstate 880 was demolished soon after the earthquake, and was not rebuilt until July 1997. The rebuilt highway was a single- rather than double-deck structure, and was re-routed around the outskirts of West Oakland, rather than bisecting it, as the Cypress Street Viaduct had done. The former route of the Cypress Street Viaduct was reopened as the ground-level Mandela Parkway.
• Embarcadero Freeway, California State Route 480: Earthquake damage forced the closure and demolition of San Francisco's incomplete and controversial Embarcadero Freeway (State Route 480). This removal opened up San Francisco's Embarcadero area to new development. The elevated structure, which ran along San Francisco's waterfront, was later demolished and replaced with a ground-level boulevard.
• Southern Freeway, Interstate 280: Seismic damage also forced the long-term closure of Interstate 280 in San Francisco (north of US 101), another concrete freeway which had never been completed to its originally planned route. The uncompleted northernmost stub of I-280 was demolished during August–October 1995 while one connecting ramp between northbound I-280 and southbound US 101 was opened in December 1995. The full I-280 project was completed in late 1997.
• Central Freeway, U.S. Route 101: San Francisco's Central Freeway (part of US 101 and a key link to the Bay Bridge flyover) was another concrete double-deck structure which faced demolition because of safety concerns. Originally terminating at Franklin Street and Golden Gate Avenue near San Francisco's Civic Center, the section past Fell Street was demolished first, then later the section between Mission and Fell Streets. The section from Mission Street to Market Street was rebuilt (completed September 2005) as a single-deck elevated freeway, touching down at Market Street and feeding into Octavia Boulevard, a ground-level urban parkway carrying traffic to and from the major San Francisco traffic arterials that the old elevated freeway used to connect to directly, including Fell and Oak Streets (which serve the city's western neighborhoods) and Franklin and Gough Streets (which serve northern neighborhoods and the Golden Gate Bridge).
• State Route 17: The mountain highway was closed for about one month because of a landslide. The route crosses the San Andreas Fault in the Santa Cruz Mountains, near the earthquake's epicenter.

• State Route 1: In Watsonville, the Struve Slough Bridge collapsed, with concrete/steel support columns punching through the bridge deck like toothpicks. The highway was closed for several months until it could be demolished and rebuilt. Another section of Highway 1 through Monterey suffered damage and had to be rebuilt as well. Additionally, the bridge carrying Highway 1 over the Salinas River near Fort Ord was damaged and subsequently rebuilt.
• Bay Area Rapid Transit: The BART rail system, which hauled commuters between the East Bay and San Francisco via the Transbay Tube, was virtually undamaged and only closed for post-earthquake inspection. With the Bay Bridge closed because of its damage, the Transbay Tube became the quickest way into San Francisco via Oakland for a month, and ridership increased in the three work weeks following the earthquake, going from 218,000 riders per average weekday to more than 330,000 post-quake, a 50 percent increase. BART instituted round-the-clock train service until December 3 when they returned to their normal schedule.
• Transbay Ferries: Ferry service between San Francisco and Oakland, which had ended decades before, was revived during the month-long closure of the Bay Bridge as an alternative to the overcrowded BART. A ferry terminal was put together in Alameda, and the Army Corps of Engineers dredged a suitable ferry dock at the Berkeley Marina. Additionally, the demolition of the quake-damaged Embarcadero Freeway led to the Ferry Building Terminal renovation, increasing the efficiency of ferry service to the peninsula. The passenger-only service proved popular and continues to expand its service.