"Everyone knows about the San Andreas fault, but the second most hazardous area in the West runs through Eastern Idaho here," says BYU Idaho professor of geology, Robert Clayton.

Parts of Idaho, including Pocatello are in the extreme risk category. Idaho Falls borders that area. Experts says old brick buildings in particular could crack and crumble in a quake.

In fact in the last half century two major earthquakes have struck our region.

The deadly Borah Peak earthquake back in 1983 registered 7.3. It caused death and destruction in Challis when brick walls literally crumbled.

The 7.7 quake at Hebgen Lake in Yellowstone toppled part of a mountain and caused masonry walls to crack as far away as Idaho Falls.

"There are small earthquakes every week somewhere in Eastern Idaho, but as far as quakes big enough to damage buildings there are probably only a few every decade," explains Clayton.

The central mountains, southeast highlands and Teton valley are the main areas of activity.

But maps of major faults show a huge one under Jackson, Wyoming, as big as the one that caused the Hebgen Lake quake.

Clayton says it would probably be felt as far south as Provo and as far north as the Canadian border and knock down every log cabin in Jackson.

Are we prepared if a disaster like an earthquake hits? Beneath the law enforcement building in Idaho Falls is an emergency management center that would spring into action.

There are contingincy plans for everything from earthquakes to blizzards to what would happen if the dams at Ririe or Palisade would fail. Other local governments are also prepared.

Considering the possible earthquake risk our cities have been pretty lucky so far, but as far as the big one is concerned BYUI geology professor Robert Clayton says it could happen any time. He said it's not a matter of if it happens, but when.