Sarah K. Nathe
Senior Program Planner
Coastal Region Earthquake Program
California Office of Emergency Services
Oakland, California

It may be a truism to say that effective emergency response requires mobility and access to damaged areas, but it doesn’t hurt to emphasize that fact as we contemplate the probable transportation impacts of scenario quakes for the Bay Area. If these estimates are even somewhat accurate, access and mobility are going to be severely limited, and emergency responders will be hampered in getting to where they are needed. Such a realization has prompted California OES, in concert with some counties and cities, to examine our assumptions about response capabilities after a quake, and to change the ones that are obviously incorrect. We believe we are now basing our plans for response on some realistic, if ominous, premises and observations.

The geography and topography of the Bay Area limit access to the region and mobility within it. Major transportation routes are on poor soils, cross major faults or bodies of water, and run through narrow corridors with infrastructure such as gas pipelines and hazardous materials plants. And we refer here not only to roads and highways; rail routes, airports, and harbor facilities are in the same vulnerable areas. With all transportation systems in such perilous locations, they can be closed by any number of earthquake impacts: fault rupture, shaking, landslides, and liquefaction; or by secondary effects such as fires, the collapse of other structures, or hazardous materials releases.

These multi-modal points of failure will make it very difficult to get emergency responders to serious incidents. And surface arterials that are not closed by the impacts mentioned above will quickly be congested and/or gridlocked by the traffic that will flow onto them from closed routes. Fire fighters, emergency medical personnel, urban search and rescue squads, law enforcement officers, and utilities repair teams will be delayed or prohibited from going where they need to go in the first minutes and hours. It may be virtually impossible to transport injured people to hospitals, except by helicopter. Debris removal, which must begin almost immediately after a quake, will be complicated by an inability to get heavy equipment into the affected areas. Care and shelter for survivors won’t be provided efficiently if government and voluntary agencies can’t send personnel and supplies into the places where they are needed.

Repair and opening of some of the disrupted roads will be one of the highest priorities, for without them, nothing else can get done. Also critical will be traffic control and the limiting of some open routes to emergency responders only. Responders may be required to use creative and flexible methods of surface transportation such as motorcycles and bicycles, water transport should be quickly pressed into action, and transit systems and schedules must be reconfigured and revised in order to both carry customers who routinely rely on them and to relieve some of the automobile congestion that will otherwise result.

City and county governments will bear the immediate burden of response within their jurisdictions because the assistance they might get from mutual aid systems or state agencies will inevitably be slowed by lack of access and mobility. The state and federal governments will stage people and supplies in the periphery of the area—for example, at Travis AFB in Fairfield—and begin to move them into the Bay Area using helicopters and boats. But all of this will take timeÑperhaps days. All the more reason for cities and counties to promote the formation and training of neighborhood response teams.

We have not had transportation disruptions of this magnitude in our two recent major quakes in California. Though both the Loma Prieta and Northridge earthquakes caused dramatic and photogenic damage to some roads and bridges, neither of them closed large numbers of surface roads or rendered emergency responders immobile. There were plenty of alternate routes for fire engines, ambulances, and public works vehicles to use.

The 1995 Kobe, Japan, earthquake may best illustrate the amount of traffic chaos we could experience in a Bay Area temblor. In that magnitude 6.7 quake, major freeways and highways, most bridges, railroads and commuter trains, and port facilities were seriously damaged and closed immediately and for some time thereafter. For a number of days there was no governmental attempt to control traffic or limit the few open arterials to response purposes. As a consequence, there was gridlock on most routes into the damaged areas, emergency vehicles were bogged down in it, as were the pieces of heavy equipment needed to clear away the debris that had blocked some of the routes in the first place.

Among the primary and secondary earthquake effects that disrupted transportation were fault rupture, excessive shaking, liquefaction, landslides, structures (elevated freeways and train tracks, buildings) that collapsed onto roads and blocked them, utility poles and trees, fires, and traffic. Getting people to hospitals was next to impossible. The port facilities were extensively damaged by liquefaction and it was a day or two before even small craft could dock at makeshift docks along the collapsed quay walls. The two airports in the area were useable by planes, but surface traffic couldn’t easily reach them on the closed or congested roads and streets. A week after the quake there was a crisis with some of the 5000+ dead bodies: transporting them to nearby crematoria was going too slowly because blocked roads limited the number of trips that could be made.

Our own recent experiences, our observations of Kobe’s problems, and our damage scenarios have obvious implications for Bay Area transportation and emergency planners at all levels of government and in the private sector. It is quite apparent that we will face serious difficulties in getting from Point A to Point B following a major earthquake. The better we can anticipate and think through the obstacles we may have, the more efficient will be our response, and the additional lives and property we will save.

(Visit http://quake.abag.ca.gov/eqtrans/eqtrans.html for more documentation on this topic.)