Work Zone Driving Tips

During construction of the Westbound I-70 Mountain Express Lane, drivers will encounter narrower lanes, temporary concrete barriers along the shoulder and median to protect workers, reduced speed limits, lane closures during off-peak travel hours, and shifting lanes to divert moving traffic around work zones. These conditions make it critical for you to:

  • Pay attention to changing roadway conditions
  • Heed work zone speed limits and directional signs
  • Avoid distractions when driving
  • Watch for workers along or in the median and shoulder areas of I-70
  • Leave plenty of room between your vehicle and the one ahead

Mountain Driving Tips

Driving through Colorado’s high country offers unique challenges even without the presence of construction activities. Steep uphill and downhill grades can put an extra strain on your vehicle, and roadway curves and rock formations can affect sight distances. With this in mind, here are some tips for driving through the mountains:

  • To prevent overheating, turn off your air conditioner and roll down the windows when traveling up a steep grade. Running the air conditioner puts extra strain on your engine and might cause your vehicle to overheat.
  • If your car is struggling up a hill, shift into a lower gear so you can maintain a consistent speed.
  • If your car is starting to overheat and you can’t immediately pull over, turn your car’s heater to the highest setting as you would on a freezing cold morning. This can help “bleed off” some of the engine’s extra heat which might buy you some time until you can safely pull over.
  • When driving downhill, use your engine and transmission to slow the car down instead of continually pushing on the brake pedal which can burn out your brakes. Shift to a lower gear (use “L” or “2” is you have an automatic transmission) before starting downhill to help slow the car down.

  • Keep an eye out for animals, particularly at night.
  • Make sure you have enough gas if traveling through remote areas.
  • If you’re driving slowly, pull into a turnout or move over to the right on a straightaway to let faster-moving traffic pass.
  • Give some extra space between your vehicle and the one in front of you since sudden stops can occur at any time

Traction Law

Anyone driving the I-70 mountain corridor between Morrison and Dotsero from Sept. 1 to May 31 needs to comply with the state’s Traction Law. 

According to this law, no matter what kind of drive train your vehicle has (all-wheel drive, four-wheel drive, front-wheel drive or rear-wheel drive), you need to have tires with at least 3/16” tread depth. If you do not have all-wheel or four-wheel drive, your tires need to have a mud and snow (M+S) or winter (mountain-snowflake) designation or have an all-weather designation from the manufacturer. These designations can be found on the tire’s sidewall.

For more information about the state’s Traction Law, visit

New Technology

To improve driver safety along the I-70 mountain corridor, Smart Work Zone technology signs are being activated along the corridor. These signs include truck warning system signs placed in various locations during construction and a permanent queue warning system sign placed along eastbound I-70 near the US 40/Empire interchange.

The truck warning signs work in conjunction with roadway sensors placed in areas where trucks are frequently entering the highway. When a truck passes the sensor, a variable message sign farther back along the I-70 corridor starts to flash, warning motorists in time to slow down and yield to the slow-moving trucks.

The queue warning sign works in much the same way by interfacing with roadway sensors that detect when travel speeds start to slow down and traffic volumes start to increase so drivers farther back can slow down and avoid rear-end collisions.

Colorado: The Official State Web Portal