The West Coast is ripe for an earthquake early-warning system similar to the one that bought Japanese citizens and businesses precious seconds before the crippling force of the March 11 quake struck their country.
But it wouldn’t be cheap, costing some $20 million a year over several years to build a network of earthquake sensors, data transmitters and information receivers stretching across the fault-ridden West Coast.
Those were some of the key findings of earthquake scientists from Washington, Oregon and California who gathered Monday and Tuesday at the University of California at Berkeley to explore the feasibility and rough costs of an earthquake early-warning system.
Their enthusiasm was tempered by the federal budget crisis, which makes funding such a system an uphill battle.
“We’d like to move forward, but the budget is a problem,” said Doug Given, earthquake early-warning coordinator for the U.S. Geological Survey. “I hope it won’t take a killer quake to build the system.”
The benefits of even 30 seconds of advance warning are many, the earthquake scientists said. It would be enough time for trains to slow down before they derail, prevent planes from landing or taking off, help schoolchildren and office employees duck and cover, and give factory operators time to shut down sensitive equipment.
An early-warning system would be useful for all three types of earthquakes experienced in the Pacific Northwest, noted Bill Steele, a seismologist at the University of Washington. For example:
The Cascadia subduction zone off the Washington and Oregon coasts is capable of producing huge earthquakes equal to what happened in Japan. The most recent major rupture where the oceanic and continental plates converge was in 1700.“When the Cascadia subduction zone ruptures again, this system could provide four minutes of warning, in an ideal case, that strong shaking is headed to the population centers of western Washington and Oregon,” Steele said. “It could also speed tsunami warnings to coastal communities.
Alerts from a deep earthquake under Puget Sound, akin to those in 1949, 1965 and 2001, could arrive tens of seconds before the damaging shaking began.
People living next to the epicenter of a shallow crustal earthquake wouldn’t get much warning. However, because the damaging waves of energy from a quake travel about two miles per second, someone living in Olympia would receive about 30 seconds of warning if a shallow earthquake on the Seattle fault occurred.
In Japan, Tokyo received up to 30 seconds of advance warning, while Sendai, a city near the epicenter, had five to 10 seconds of warning.
A West Coast early-warning system is not a cure-all, said Richard Allen, associate director of the U.C. Berkeley Seismological Laboratory. But it would complement other pieces of earthquake preparedness, including strong building codes and emergency planning.
“We don’t know when the next damaging quake will happen,” Allen said. “But when it does, we’ll wish we had an early-warning system.”
As a first step, the earthquake scientists are hoping to generate interest in a prototype system funded with public and private money.
But ultimately, its the federal government’s responsibility to provide the base support for the system, Steele said.
A system with a price tag of roughly $80 million over five years would be built in California first, followed by a Pacific Northwest addition estimated to cost $65 million over five years, the scientists recommended.
“It’s a proven system; they just did it in Japan,” Allen said.
John Dodge: email@example.com