Cascadia earthquake and tsunami. Oregon is not prepared for a megaquake, and few areas are, Madin says. He says Japan is the most prepared, and look at the results of their megaquake. The 2011 earthquake and tsunami resulted in more than 15,000 deaths. Before 1974, there were no specific building requirements in Oregon to make sure structures were built to withstand major quakes, and design codes have only been adequate for the megaquake since 1993, so many structures are not designed to resist such a large earthquake, Madin says. Earthquake fast facts On top of that, we have a lot of mountainous terrain that is highly susceptible to landslides, large areas that are susceptible to liquefaction, and 300 miles of coast that will be inundated by tsunamis that will arrive within 15 to 20 minutes of the earthquake and may locally reach elevations of 100 feet above sea level, he says. It is these factors that led the Oregon Resilience Plan to conclude that in a worst-case scenario, 10,000 people could be killed, and large areas of Oregon could be without transportation, electricity, water and sewer for several months to several years. The damage could result in $30 billion in economic losses. Madin says $30 billion is almost certainly an underestimate, and death estimates could also be off. Based on the study of geologic features that record prehistoric earthquakes, scientists