99% of people on the coast would not need to evacuate for a distant tsunami.The really deadly tsunami, the one people on the Northwest coast have to prepare for, is one that will happen locally.
That is, when someone at their head quarters sees an earthquake off the coast, he can press a button and make all the sirens on the coast sound the alarm.
The Oregon coast sirens: The sirens on the Oregon coast are not centrally controlled.
No one in Japan expected a 1,000-year event to happen off their northeastern coast.
An 8.1 earthquake had been forecast as the maximum for the area, and a 7.5 at the Fukushima plant.
We’ve learned about the cost of that underestimation.
Chile: The difference between Japan’s subduction zone tsunami and the one in Chile in February 2010 is that in Chile, there were no seawalls, and no warning systems to sound the tsunami alarm.
Portland earthquakes: There are three known major faults in the Portland area.
The apparent recurrence period for large earthquakes on the faults is once every 2500 years.
In Japan, the homes and other buildings were generally not built to sustain tsunami damage.
Many wood-frame houses were broken off their bases by the tsunami: without an anchor in the ground, the homes were carried off by the rushing waters.
Tsunami damage around Brookings and Oregon’s south coast: The Japan tsunami did million of damage to the port at Brookings, quite a bit of damage at Gold Beach, a little bit at Port Orford, and a minuscule amount as far north as Depoe Bay.