The state of Colorado has long required commercial trucks to chain up during storms on highways, especially on the I-70 Mountain Corridor, a stretch of road particularly dangerous during the winter. Just a few days ago, the interstate saw two separate 20-car and 30-car pileups just 15 minutes apart. Now, according to a new set of traction law updates, everyday vehicles are also expected to follow truckers’ example.
Any two-wheel drive (2WD) vehicle — front- or rear-wheel drive — traveling on I-70 between Dotsero and Morrison from September 1 through May 31 must carry a set of snow chains or an approved traction device. The requirement doesn’t mean drivers must drive with chains for that entire period. Instead, they must be ready to use them whenever the Colorado Department of Transportation (CDOT) or Colorado State Patrol (CSP) activates the Passenger Vehicle Traction or Chain Laws during inclement weather.
A large portion of winter closures and backups stem from unprepared passenger cars that lose traction on grades or become stuck in sudden snow squalls. When the weather deteriorates, truckers are accustomed to pulling over and chaining up. 2WD vehicles are now expected to follow a similar protocol.
What happens if you’re not prepared
The updated law distinguishes clearly between drivetrain types, but no one is exempt from preparation. For 2WD vehicles, the requirements are strict. They must carry chains (or an approved alternative traction device) for at least two tires whenever traveling the corridor in winter. A $50 fine plus surcharge awaits all who fail to comply. And if you end up obstructing traffic due to a lack of traction, you can face up to $500 in penalties.
All-wheel drive (AWD) and four-wheel drive (4WD) vehicles — yes, there’s a difference between the two – are also subject to scrutiny. While they aren’t required to carry chains under normal traction law activation, they must run tires that meet state standards, which means they must be winter-rated, all-weather, or M+S tires with a minimum tread depth of 3/16-inch. A vehicle that fails this requirement is treated as non-compliant, even if it’s AWD. During the most severe conditions, when the Passenger Vehicle Chain Law is activated, every vehicle on the road, regardless of drivetrain, must chain up.
Officials also recommend practicing installation at home, in dry conditions, and not on a shoulder during a storm. Agencies advise reducing speed, increasing following distance, clearing snow from the entire vehicle, and giving snowplows significant space. Passing a tandem plow formation is now a Class A offense due to the whiteout conditions it creates.
