Hundreds of earthquake sensors to be installed across Alaska

ANCHORAGE (AP) -- Three hundred earthquake monitors will be installed across Alaska in the coming years.

A panel of scientists and engineers now is deciding where to locate the first 10 monitors, which will arrive in May. Many of them will be installed in Anchorage, where some will be wired into buildings and others placed in the ground to sense what happens at different depths.

The monitors are part of a national drive to expand and improve upon an existing, loosely connected network of seismic sensors across the country. Eventually, some 7,000 monitors will be installed nationally.

Most of the monitors will be installed in urban areas that are earthquake prone. It is expected to take up to seven years to get the system in place.

By watching what happens to buildings when the ground shakes, engineers and architects should be able to design structures more likely to withstand bigger quakes. The system also should increase the efficiency of emergency response teams.

The program, directed by and financed through the U.S. Geological Survey, costs $170 million to install and $47 million to operate annually.

Existing earthquake monitoring systems in the United States are fragmented and in many places outdated. Some are operated by governments, some by universities, some by individuals.

''Monitoring hasn't kept pace with increased risk, especially in heavily populated urban areas'' that have grown up over and around seismically unstable ground, said John Aho, an Anchorage structural engineer and chairman of an advisory committee formed to decide where to locate the monitors installed in Alaska.

Many of the monitors will be installed in and around Anchorage, but seismologists also want to put them in Fairbanks and Valdez, maybe along the trans-Alaska oil pipeline, on the slopes of volcanoes along the Aleutian chain. Some communities, such as Larsen Bay on Kodiak Island, which has been rattled by three quakes of magnitude 6.5 or greater in the past two years, want better instrumentation, said Roger Hansen, the state seismologist.

Federal agencies say when earthquake damages are averaged out, the cost comes to some $4.4 billion a year in the United States -- more than for any other kind of natural disaster.