Touring the local landslides
EAGLE COUNTY Gravity works. That means things like rocks, or even hillsides, are usually trying to fall down.To explain how gravity and the falling-down process works locally, the Vail Symposium Wednesday hosted a lecture and tour of local geologic hazards by Colorado State Geologist Dr. Vince Matthews.The classroom was mostly full during Matthews lecture, with more than 30 people signed up. Many of those people were like Jim Abbee of Eagle-Vail.Ive always had an interest in geology, Abbee said. When I drive up and down the highway Im fascinated by the landscape.That landscape poses a lot of potential hazards. Matthews defined hazards as things nature does normally, but that get in the way of people.Locally, that mostly means landslides and rockfalls, especially since theres been a lot of building on the valley floor, which gravity will eventually pepper with rocks and other debris.
Landslides can sit idle for years, Matthews said. In fact, theyre everywhere in the mountains. The trouble will sometimes come if a road gets cut through the base of a landslide.
An obvious place to see that is between Eagle and Gypsum, where U.S. Highway 6 has triggered what Matthews called a textbook slide thats easily seen from Interstate 70.I was driving to Glenwood Springs one day and saw it, Matthews said. By the time I stopped to take a picture, I was probably a half-mile past it.Slides like the one in Red Canyon can be triggered when something like a home foundation lets gravity take material from the top of the slide to the bottom.Gravity works on boulders, too. Locally, a giant ditch above an East Vail neighborhood catches plenty of rocks. But, Matthews said, the ditch should have gone a little farther west.That ditch, carved into the hillside above the homes, was paid for in part by property owners agreeing to pay a bit more property tax. Owners to a little west of the existing ditch didnt participate in the project.A few years later, in 1997, a half-dozen boulders slammed into some condos. One of those boulders rolled into a bedroom where a woman would have been sleeping if she hadnt taken on a few extra hours at work.That was totally preventable, Matthews said.Preventing damage from rockslides and other hazards is fairly simple, Matthews said. And, he added, its far less expensive to deal with hazards before building than after.A condominium complex in Glenwood Springs that has been dogged by slumping soils, rockfalls and other hazards was recently awarded a $12 million settlement to fix the damage.
One of the biggest hazards, though, is one people in Colorado dont give much thought to: earthquakes.The Denver area was hit by several quakes in the 1960s, triggered by pumping industrial waste into a fault. But mountains are created by faults, which continue to move long after theyve finished thrusting up peaks.It turns out the Gore Range is among the youngest, and most active of those faults. State experts have estimated that if a full-strength quake hits the Front Range, the damage would be in the billions, with thousands of dead and injured.It could be our (Hurricane) Katrina, Matthews said. And nobodys paying attention.Out of the classroom and on the road, people who signed up for the seminar were having a great time.Its very interesting if you live here, said Alberta Johnson of Singletree. You can impress your relatives by telling them about alluvial fans.This is the second year Matthews has come to talk about local geology, and several people on Wednesdays tour had taken last years excursion, which covered the area between Wolcott and Glenwood Springs.Im a geologist, too, said Nick Kuich of Edwards. Its very interesting to me to learn about the local geology.Evelyn Strauch of Cordillera had just finished a couple of books about volcanoes.This is a terrific complement to those, Strauch said. And I love to know about the local environment.Staff Writer Scott N. Miller can be reached at 748-2930, or firstname.lastname@example.org.Vail Daily, Vail Colorado