Return to winter driving is reason for caution; don't pass plows

January 10, 2018

Snowplow drivers are asking for help from citizens following a handful of near misses already this winter involving citizens' vehicles and snowplows.

Driving near snowplows requires care and patience, and snowplow drivers are reporting risky behavior from drivers this winter, including passing the Wyoming Department of Transportation's new tow plow in Fremont County, passing other trucks and tailgating.

WYDOT snowplows are out on the highways every day and many nights, and WYDOT employees are attempting to provide a safe, high quality and efficient transportation system for the citizens of Wyoming.

WYDOT deploys many bright yellow snowplows when battling snowstorms, and when working the roads, these plow trucks have amber, red and blue flashing lights mounted on top of the cab and on the back of the sanders.

These snowplow professionals need cooperation from drivers so they can do their jobs and keep the road safe for drivers. Give them room to operate.

"Stay well back from operating snowplows," said WYDOT District Maintenance Engineer Lyle Lamb of Basin. "They are spreading sand and anti-icing and de-icing chemicals on the roadway. It's always a good idea to stay back from snowplows while their operators are doing their jobs."

Snowstorms this winter haven't yet brought deep snow to northwest Wyoming's valleys. "Our guys have been out there spreading sand and using salt brine to break up ice," Lamb continued. "Please drive on the areas where sand the chemicals are being applied. This driving behavior helps break up the snow and ice. Please understand what our guys are doing, and please, don't pass the plows."

With limited visibility, snowplow drivers can't see vehicles behind them if the vehicles are too close to the plows. As the old adage goes, if you can't see the plow driver's mirrors, he/she can't see you.

"Remember, the safest driving surface is behind the plow. If you must pass, don't pass on the right into the plume of snow being moved," Lamb said. "Be sure on two-lane highways that you have plenty of time to pass. Keep a close watch, these huge plows often stir up their own whiteout conditions while doing their work."

A tow plow was used extensively for the first time last winter in the Riverton and Lander areas, and other parts of the state. A second tow plow in northwest Wyoming will be assigned to the Cody and Powell areas this spring.

Lamb said the tow plow is a trailer mounted, 26-foot plow that is towed behind a 10-wheeled plow truck. It has the capability of plowing and treating the highway with salt brine on an entire additional lane of roadway at normal highway speeds when completely deployed. The entire trailer unit shifts to the right, using movable axles on the trailer unit as well as hydraulic controls between the truck and trailer. It can take the place of another plow truck by allowing one truck to plow two lanes of roadway, or a single lane of roadway and an eight-foot shoulder."

Goals for operating a tow plow during the past two winters on Fremont County highways include improved highway safety and snow-plowing efficiency.

"The tow plow does the work of two trucks, and it has proven effective in Fremont County. The problem we've had early this winter is citizens passing the tow plow while it's operating," Lamb said. "Our drivers have even reported citizens passing the tow plow on the right side of the highway while it's discharging snow from two lanes of highway in the same direction. It's unsafe and could result in a costly crash where someone could be seriously injured, or worse yet, the person could die."

Snow plan helps WYDOT set priorities

WYDOT maintenance crews have a plan of attack during winter storms. Limited resources require priorities to be made.

A snow removal plan goes into action during storms, creatiing a prioritized list of routes based on traffic counts and school bus routes. This plan is divided into four levels: high volume, medium volume, low volume, and closed. The snow plan is available at This web site can also be used to access road and travel information, including web cameras and road closure information.

High volume roads are plowed up to 24 hours a day, and usually consist of interstate highways and urban routes, such as Interstate 80 in southeast Wyoming.

Medium routes are plowed to keep them passable and reasonably safe, and are a secondary priority to high volume routes. Low volume routes are only serviced after high volume and medium volume roads have been cleared, and are only plowed during daylight hours. Closed refers to seasonally closed roads, where the cost of keeping them clear outweighs their use.

Exceptions to the plan include school bus routes, which are plowed at least twice a day, regardless of their priority.

WYDOT uses liquid de-icers and anti-icers to battle ice on roads

In the course of winter maintenance, WYDOT treats roads with liquid de-icers and anti-icers to keep ice bonding to our roadways, or to remove the ice if it has already formed.

These mixtures include salt/sand, liquid salt brine, magnesium chloride and beet juice. When snowfall can be predicted, some of these chemicals are sometimes applied to roads before storms to help keep snowpack from accumulating, and to assist with the removal of snow after the storm.

"We try to prevent the snowpack from forming, but we can't always do that. Chemicals do help with the removal of the snowpack after the storm," Lamb said.

Other chemicals are used continuously to help battle snowpack and icy conditions.

"We do what is called 'pre-wetting.' This is where we use a salt/sand mixture that has been pre-wet with a chemical, usually salt brine (salt mixed with water). This helps the sand stick to the road," Hallsten said.

Salt, or sodium chloride, is the most common and cheapest tool for fighting ice. Salt has an important role in ice removal. Using salt on roads lowers the temperature at which ice will melt, and helps to prevent the formation of ice at lower temperatures. But when temperatures drop below 15 degrees Fahrenheit, salt becomes ineffective.

Another compound, GeoBrine, is another WYDOT tool for battling ice on our highways. Also known as beet juice due to its association with sugar beets, the sticky, red solution is composed of 60 percent salt brine and 40 percent beet juice, which give it the red color. GeoBrine is often used as a preventative action when roadways are pre-wetted prior to storms.

Salt brine freezes at 6 degrees below zero when mixed properly, while GeoBrine freezes at 26 below zero.

Beet juice works by basically stopping the ice and snow from bonding to the pavement during the storm, which allows WYDOT maintenance workers to plow off excess moisture easier and quicker, which clears roads faster. Pre-wetting roads helps WYDOT to provide safer conditions for drivers during the storm as well. This helps maintenance crews from spending excessive amounts of time chipping ice off highways throughout northwest Wyoming.

Supplementing beet juice mixtures in WYDOT's battle against icy road conditions allows ice and snow to melt at lower temperatures, and also provides a preventative coating on the highways which lasts longer, giving crews a chance to get more snow and ice of the roads in a timely manner.

"We try to prevent the snowpack from forming, but we can't always do that," Lamb said.

While research verifies fewer accidents occur on treated highways, these de-icers and anti-icers can be sprayed up on vehicles from tires and wind.

"After storms, we'd suggest washing your vehicle to minimize the long-term effects of these chemicals," Lamb said.

Information links may help in planning your winter outings

  • National Weather Service (Riverton)
  • WYDOT road conditions –
  • WYDOT road conditions – 1-888-WYO-ROAD
  • Northwest Wyoming Twitter: @d5pio or @WYDOT_Northwest
  • WYDOT 511 Mobile Smart Phone App
  • 511 Notify – Dial 511 on your cell phone to obtain road information.  This system can  also be enabled to deliver road alerts as text messages to your phone or emails to your computer or phone on routes that the user identifies. Go to WYDOT's 511 Travel and Information website and choose the 511 notify icon to set-up your account.
  • And in case of emergency, the following number may be contacted for assistance: Wyoming Highway Patrol (24 hours per day) - (800) 442-9090.

Questions about this news release may be directed to WYDOT Public Relations Specialist Cody Beers at 856-1341.