A chain-reaction fatal collision at the start of Thanksgiving travel last Wednesday was a strong reminder of the danger posed by fast-changing winter weather conditions in the Inland Northwest.
One person died in the four-vehicle crash involving a semitruck, two passenger cars and a pickup on a stretch of freeway that had iced over.
What was actually a series of collisions left debris strewn across the eastbound lanes and shoulders with the semitruck sprawled down the embankment on Interstate 90 at an overpass above Medical Lake-Four Lakes Road near Cheney.
Washington State Patrol troopers at the scene said an icy roadway and drivers going too fast for conditions led to the accident.
The heavier amount of holiday traffic may also have been a factor.
Apparently, a thick layer of fog had formed overnight along the freeway about 11 miles southwest of downtown Spokane, causing ice to stick to the pavement and leaving white hoarfrost on trees, grass and freeway shoulders.
Trooper Jeff Sevigney said the overpass itself was extra slippery because the pavement had become colder than the approaching freeway pavement, likely because the overpass had cold air circulating beneath it.
Bridges and overpasses are known for being icier than other sections of roadway. Shaded sections of road can also be dangerous for black ice.
Approaching drivers may not have suspected the icy conditions when they hit the slippery surface. A pickup initially slid out, then crossed the median into the westbound lanes where it clipped the westbound semi, which had swerved to avoid the collision.
That sent the semi through the median into the eastbound lanes where it collided with two passenger cars, killing a woman in one of them. The semi then plunged down the embankment.
Sevigney said people “need to use caution. It’s wintertime in the Northwest.”
He said he has investigated other accidents caused by similar circumstances, and urged drivers to watch out for unexpected icy stretches of roadway.
Sevigney said areas around Spokane where the terrain rises, including the West Plains, are susceptible to the conditions encountered during Wednesday’s accident.
Fog that freezes is more likely late at night through mid-morning this time of year. Frost accumulating along the roadway and surrounding landscape is a clue that danger is near.
Vehicles with outside thermometers will help drivers know when black ice may be present.
“This is not an uncommon occurrence in our area,” he said.
Keep your vehicle supplied, prepared
In addition to keeping an eye out for black ice and other unexpected icy stretches, drivers should remember to carry winter emergency supplies, public safety experts said.
Those include tire chains, flares or reflectors, extra clothing, gloves, a hat, boots, a blanket, food or snacks, water, a first aid kit, an empty container with a lid, a flashlight, a charged cellphone, a shovel, an ice scraper and snow brush, and sand or cat litter.
Having extra fuel in the tank is also a good idea.
Drivers should consider the possibility that a collision could disable their vehicle, causing them to lose heat and light. Emergency goods will keep you safe and warm until help arrives.
Also, being caught in a traffic jam or slowdown could consume onboard fuel more quickly than anticipated, making it important to have an extra supply in the tank.
The Washington state Department of Transportation recommends getting your car in top working order with properly inflated tires and adequate tread. The battery, belts, hoses, radiator, lights, heater and wipers all need attention to maintain them in working order.
Work will restrict traffic on Mission
In Spokane Valley, westbound traffic on Mission Avenue between Bradley and Thierman roads will be reduced to one lane from 8 a.m. to 3 p.m. today through Friday.
Flaggers will direct traffic. Access to businesses will be maintained.
Wider chain-up area open near I-90 pass
A larger chain-up area on I-90 3 miles east of Snoqualmie Pass has been opened.
The DOT has implemented a new overhead sign system to direct chaining up.
Trucks and passenger vehicles are being asked to follow the directions on the sign to find a space in the chain-up area.
Double parking by trucks is no longer allowed.
The wider area will reduce the risk of collisions between moving vehicles and drivers and passengers who get out of their vehicles to install tire chains.
The use of overhead signs is an extension of the state’s expanding digital communications network known as intelligent transportation systems.