Wednesday, January 6, 2010

Temps help road prep crews

Kentucky Transportation Cabinet crews are getting a break from warmer than expected pavement temperatures today. Warming pavement has allowed highway crews to increase the amount of pre-treating of highways they can complete in advance of an approaching winter storm.

Crews anticipate being able to pre-treat highways until later afternoon and maybe into the evening hours tonight to help prepare highways for winter precipitation. The U.S. Weather Service has issued a winter storm warning for most of Western Kentucky tonight through Thursday.

Under normal conditions salt brine sprayed onto road surfaces will dry to a fine powder and remains there until it is activated in the early hours of a winter weather event. However, brine can freeze instantly instead of drying when pavement surface temperatures fall below 25 degrees, running the risk of creating a hazard instead of a benefit for motorists.

At this time, crews plan to start pre-treating “A” Snow Priority Routes which are generally Interstates, Parkways and U.S. Highways first, then move to “B” Snow Priority Routes if weather and time allow. Due to temperatures limiting the time available to pre-treat, highway engineers say it is hard to predict how much pre-treating can be completed before the winter precipitation hits Wednesday evening.

Motorists are advised to be alert for slow moving trucks on area highways as crews try to complete as much pre-treating as possible during the limited window of opportunity.
Motorists need to be aware that even on the limited number of highways that crews are able to cover, temperatures will be cold enough to greatly limit the effectiveness of pre-treating.

Driving conditions are likely to deteriorate fairly quickly on untreated highways when the snow starts and may not be much better on road surfaces that crews are able to pre-treat. Even as crews spread salt after the precipitation hits, cold temperatures, wind, and the threat of drifting snow will severely limit the ability of highway crews to improve driving conditions.

The Salt Institute cites both U.S. and German studies that found treating highways with salt can reduce vehicle crash injuries by 80 percent or more during winter weather. However, in temperatures below 20 degrees the ice melting ability of salt and other ice-fighting chemicals is greatly reduced.

Road condition reports for major routes in Kentucky are available by calling 511 or by visiting the 511 travel and traffic information Web site at http://511.ky.gov.

A list of Snow Priority Routes for District 1 counties is available at http://www.transportation.ky.gov/D1/Snow.htm.

Motorists are encouraged to monitor local news media to get regular updates on weather and road conditions during this winter weather event.