Officials consider 9.0 quake impacts

Wahkiakum County officials got something to think about Tuesday--the likely impact of a 9.0 magnitude earthquake off the coastline.

The shifting in tectonic plates along the Cascadia fault would likely cause several minutes of shaking, and in 20-30 minutes, a tsunami would arrive that would inundate lowlying areas along the coast.

Emergency planners from the Washington Military Department said 3,300 people would likely die, another 25,000 would be injured, and the region would experience widespread disruption of power, transportation and food distribution.

The tsunami resulting from a subduction zone earthquake is expected to cause widespread damage and loss of life in areas along the coast, said Jim Hutchinson, TFER Project Lead for the Washington Military Department's Emergency Management Division.

People would have 20-30 minutes to reach high ground, and they would have to walk, for the shaking will likely damage and block roads.

The region would experience disruption of the electric power grid. Bridges could collapse or be separated from their approaches. Communications networks would experience outages. Natural gas lines are at risk of damage, and railroad lines would likely be cut by landslides, bridge collapses or other effects of the quake. The ability of the region to produce and ship supplies such as gasoline would be disrupted.

The disruption of highways will make it difficult or impossible to carry injured persons inland to hospitals. Fuel will be scarce, and local officials will have to decide what vehicles they will mobilize.

Sewer and water mains are at risk. "A concrete pipe will probably break," Hutchinson said. "Steel or poly pipe might be okay."

Damage to railroads, highways, and buildings will disrupt the food supply. Hutchinson said some areas along the coast, such as the area north of Grays Harbor, will become "food deserts."

Hutchinson said state emergency managers are developing a response plan. Basically, he said, responders will have to come from the inland area to the coastal areas.