GLOBAL EARTHQUAKE RISK REDUCTION: CASCADIA, THE NEXT FRONTIER

The Cascadia subduction zone can cause very large earthquakes affecting from Northern California to British Columbia has not experienced a substantial earthquake in the past four centuries. Recent large earthquakes in Haiti, Chile, Japan, and New Zealand have revealed that: a) buildings and infrastructure without modern seismic resistive system are susceptible to extensive damage and collapse and the resulting loss of life, and b) buildings designed per modern seismic codes perform well but nonetheless experience significant loss of functionality and resulting economic loss. Worldwide, seismic risk hazard identification and mitigation programs have been undertaken in the past decade to improve the resiliency of communities located in earthquake hazard prone areas. Such programs are especially critical because many large metropolises are located in areas of high seismicity. Examples of such programs are the seismic risk reduction for buildings currently underway in Turkey, Haiti, New Zealand and Philippines. A large earthquake in the Cascadia region could result in widespread damage and substantial casualties because many structures in the earthquake zone use vulnerable details that have failed or experienced damage in earthquakes elsewhere. A strategic plan to assess risk to such structures and develop seismic strengthening for susceptible structures is proposed.