12/17/2012
Reed Hollinshead
ITD Communication
208-334-8881
reed.hollinshead@itd.idaho.gov
Despite more than 28 feet of snow and 50 avalanches, ITD snowfighting provides fewer closures
BOISE - ITD's snowfighters devote much of their work week to thinking about highways and bridges, so that valley drivers don't need to. In fact, few efforts are as clearly linked to highway safety or are as beneficial to motorists as the snowfighting battles waged each winter in southwestern Idaho.
The sheer volume of traffic and travelers is a big factor: the region features the largest population base and geographical
area in the state - lots of drivers and many miles of roads.
With more than 50 inches of snow accumulated in some mountain areas already this winter season, the annual battle is well under way. "When we have at least 20 inches at Banner Summit, there is potential for avalanches," said Idaho Transportation Department Avalanche Forecast Manager Bill Nicholson.
The Avalanche Forecast team, two full-time (Nicholson and Chantel Astorga) and two seasonal employees, began daily forecasting for slides in the notorious “Avalanche Alley” area between Grandjean Junction and Banner Summit Nov. 1. The 11-mile section is home to about 60 avalanche chutes and 90 percent of the avalanches in the state that affect highways.
“We evaluate the strength of the existing snowpack and the incoming stresses such as snow, water weight, wind and temperature to create an avalanche-hazard forecast," said Nicholson. "Our goal is close the highway before any avalanches release that could threaten motorists. Then we can clear the highway off safely and reopen it as soon as it is safe."
Click here for Nicholson's sound bite.
Following that plan, the unit has been able to reduce the average number of closure days on Idaho 21 significantly, despite routinely receiving more than 300 inches of snow in a winter season.
Last winter, for example, there were only 21.5 days of closure despite 338 inches of snow and 50 avalanches that tumbled down on the highway. The historic averages before and after the Avalanche Forecasting team are listed below:
With Avalanche Forecasting (last 3 years)
Avg. snowfall: 314 inches
Avg. closures: 16 days
Before Avalanche Forecasting (1999-2009)
Avg. snowfall: 227 inches
Avg. closures: 42 days
This is a tremendous service to drivers and businesses in the area. If the road is closed, the detour route adds 82 miles to the trip - if you know about the closure before you leave. Otherwise, it could add 276 miles on the southern detour or 596 on the northern detour - longer than a trip to Seattle!
The road used to be closed all winter long, every winter, as a precaution.
ITD is armed and ready to handle whatever the winter season brings. The region has switched to a winter schedule of two shifts of employees, changing between 2 and 4 a.m., that ensures 24-hour coverage on high-volume routes. ITD has 83 pieces of snowfighting equipment (de-icers, sanders, graders and plows) to clear more than 2,600 lane miles of roads in the region. This does not include another 37 loaders and backhoes that load sanders and clear turnouts.
For the latest highway and weather conditions, call Idaho Traveler Services at 5-1-1. For online updates, visit the website at 511.idaho.gov. Telephone and Web reports are available 24 hours a day and are updated as conditions change.
All ITD initiatives are linked to safety, economic opportunity, mobility and the role the department serves as an advocate for drivers and a good steward and gatekeeper for taxpayer funds.