Perhaps the most dangerous fault line in the United States stretches from the northern part of California, up along the coast of Oregon and Washington, and into Canadian waters. It's called Cascadia, and for a long time no one knew it was there.
It wasn't until the mid-1980s that geophysics recognized the fault line that existed just 40 miles offshore -- one frighteningly similar to the one which just erupted off the coast of Japan. It then took until 1995 before the state of Oregon incorporated specific provisions in its building code mandating protection against earthquakes. Many of the buildings now standing in the state were built before the provisions were adopted; the vast majority has not been retrofitted to improve safety.
If, as in the 9.0 magnitude event in Japan, one tectonic plate in Cascadia gets forced beneath another, it could result in a quake that reduces many of the buildings near the coast to rubble. It would take less than 30 minutes for the subsequent tsunami to reach shore.
The last major earthquake to hit in the region was in the year 1700; its effects could be felt all the way across the Pacific Ocean. With the region experiencing 41 quakes 8.0 magnitude or above over the past 10,000 years, geologists say it's a question of when - not if - the next one hits.
"We're overdue," warns geotechnical engineer Yumei Wang of the Oregon Department of Geology and Mineral Industries.
And for the most part, the region is unprepared. Japan has cutting-edge technology to deal with earthquakes, which is one of the reasons the terrible devastation from last week's quake wasn't even worse; the United States, by contrast, has done relatively little to prepare for a similar disaster. And with states and the federal government suffering serious budgetary woes, officials are not looking to spend money on infrastructure to project against earthquakes and tsunamis - a threat that may not seem urgent until it's too late.
According to the American Society of Civil Engineers, America's infrastructure warrants a grade of "D" overall. One in four of Oregon's bridges are structurally deficient or functionally obsolete, according to the report; in Washington, nearly 30 percent of bridges need repairs. Many of the dams in the area that protect urban areas are vulnerable.
The next Cascadia quake will "likely to be the greatest natural disaster that's ever impacted the United States," said Ian Maiden, chief scientist for Oregon Department of Geology and Mineral Industries. Maiden put the odds of such a quake within the lifetimes of people living in the Pacific Northwest at 30 percent.
"It's an event that we have to plan for, and anything we want to see survive needs to be made resilient against such an event," he said.
In Oregon, according to a 2007 study, nearly half the schools in the state face a high risk of collapse in a quake; low-lying coastal towns, meanwhile, have little to no protection against the tsunami that could result.
"We are not even close to being well enough prepared," said Wang.
That isn't going to change anytime soon. To retrofit a major building against earthquakes can cost millions of dollars, and, as the Japan tragedy illustrated, offers no guarantees. The cost of retrofitting every building in Portland alone would run in the tens of billions of dollars.
Spending that sort of money is an extremely tall order even when the economy is doing well, and when states and the federal government are suffering serious budgetary woes, as they are today, it's nearly unimaginable.
Consider: Even in San Francisco, where building codes are more stringent and a 6.9 magnitude quake caused widespread devastation more than 20 years ago, more than 17,000 structures remain unprotected today.
In light of the economic realities, officials are focusing on education and creating safe zones. There have been exceptions, such as an effort in Portland to retrofit schools, but it's a deliberate process at best: It's more than a decade until Oregon law mandates that public safety buildings be retrofitted, and an a program to retrofit all the state's schools is not scheduled for completion until 2032.
"We know that we live in earthquake country," said John Schelling, Earthquake and Tsunami Program Manager for Washington State Emergency Management. "We've been very proactive when it comes to trying to prepare our vulnerable coastal communities for this type of a threat."
That largely hasn't meant building sea walls and reinforcing buildings, however. Project Safe Haven, for example, is a "vertical evacuation" program to make sure there is safe space for coastal residents to get to in the event of a tsunami. One focus of the effort is to create artificial high ground where residents can go in the event a tsunami, through controlled burns to create safe areas and the erection of reinforced buildings.
Yet there is little money to implement the program, according to Schelling. And the meager money that goes to Washington State as part of the National Earthquake Hazard Reduction program - about $100,000 per year - is now projected to be cut in half, he said.
In Oregon, Maiden said, much of the focus has also been on education. Yet the hundreds of thousands of dollars that fund the education effort each year, which comes via a short-term term grant from the National Oceanic and Atmospheric Administration, is now threatened. The budget passed by the Republican-led House earlier this year
If there's a silver lining in the tragedy in Japan, domestic earthquake experts say, it's the opportunity to focus public attention on the risk faced at home. The disaster could boost efforts to build a tsunami-proof structure in Oregon's Cannon Beach, for example -- one that would be the first of its kind in North America. If nothing else, experts say, the Japan tragedy could prompt residents take a moment to consider that they are not immune from the same sort of devastation being felt on the other side of the ocean.
"We have a tremendous threat," Wang said. "The Japan earthquake is a tragic reminder of what the Pacific Northwest will one day experience. There's no getting out of it."