Quake study targets risk of building

HURRICANE, Washington County — A study on the Hurricane Fault in eastern Washington County will help cities and developers evaluate the seismic risk of building within the fault's boundaries, according to a senior scientist with the Utah Geological Survey.

"By anybody's definition, this is an active fault," said William Lund, a senior scientist with the UGS in its Cedar City field office and one of several geologists who worked on the Hurricane Fault study. "We have a pretty good idea of how big the last earthquake was, and a rough sense of when the last one was, but what we really don't know is how often quakes occur (on the Hurricane Fault)."

Lund is editor of the the Paleoseismology of Utah Series, which recently published the study through the Utah Geological Survey.

Building codes, hillside development and sensitive land ordinances passed by various cities in Washington County address developments in geologically hazardous locations, but predicting future problems is still a shaky business.

"Enforcement of code is a critical element, but the real challenge is trying to develop proper and reasonable mitigation steps to prevent problems in the first place," said Bob Nicholson, community-development director for St. George. "We have a Hillside Review Board that scrutinizes requests from developers, but we still spend a lot of time trying to prevent problems."

St. George city approved close to 2,000 building permits for dwelling units in 2005 and about half that last year, he said.

"As the price of real estate goes up, the demand to push the envelope goes up at the same time," Nicholson said. "Homes start to climb up the hillsides and build on flood plains."

La Verkin city manager Ben Reeves said developers planning to build near the Hurricane Fault, which runs along the east side of town, are required to provide a geotechnical report.

"There is a tremendous pressure on us with growth on the hillside," he said. "We have a fairly restrictive building ordinance, but the challenge is to balance property rights with the greater good of the community. We're getting a lot of complaints about homes going up on the hill."

La Verkin issued 111 building permits in 2005 and only 37 in 2006. This year, the city has already approved 25 permits, with a large development under way near the city's water tank on the east hill.