With winter and snowy, slippery roads right around the corner, it is the perfect time to educate drivers about Colorado’s Commercial Vehicle Chain Laws and Passenger Vehicle Traction Laws.

All commercial vehicles traveling on I-70 between Sept. 1st and May 31st, between Milepost 133 (Dotsero) and Milepost 259 (Morrison), must carry sufficient chains at all times. On all other roadways in Colorado, commercial vehicles are required to put chains on their tires when CDOT puts Chain Law into effect. When Chain Law is in effect, commercial vehicles must put chains or alternate traction devices (ATDs) on at least four of the drive wheel tires, or all of the drive wheel tires if the vehicle has fewer than four drive wheel tires. Buses are required to chain or have ATDs on two drive wheel tires. When Chain Law is active, it will be posted on the large message boards along the highway and on the fixed highway signs. You can also visit cotrip.org to see where chain law is active. Failure to comply with Commercial Vehicle Chain Law can result in a total fine of up to $1,157.

The message boards will also notify you when Passenger Vehicle Traction Law is in effect. During winter storms, or when conditions require, CDOT will implement the Traction Law. During Traction Law, all motorists are required to have at least one of the following:

  • 4WD or AWD Vehicle with at least 3/16” tread depth.
  • Tires with a mud and snow designation (M+S icon) and 3/16” tread depth.
  • Winter tires (mountain-snowflake icon) and 3/16” tread depth.
  • Tires with an all weather rating by the manufacturer and 3/16” tread depth.
  • Chains or an approved alternate traction device (auto sock or cables).

From Sept. 1st to May 31st, Traction Law is always active on I-70 from Dotsero to Morrison. Failure to comply with Traction Law can result in a total fine as high as $657.

Along with Chain Laws and Traction Laws, remember that when driving in winter conditions, slower speeds and increased following distance can make the difference between arriving at your destination
safely and being involved in a crash. Please drive safely and pay attention to the changing road and weather conditions!