Truckers in Colorado need to be aware of new chain law requirements this year. On May 20, 2024, Governor Jared Polis signed the Commercial Vehicle Highway Safety Measures bill (formerly SB24-100) into law.

A key aspect of the new law is the expansion of the number of roadways where truckers must carry chains during the fall, winter, and early spring seasons.

Previously, the law mandated that commercial vehicles on I-70 between mileposts 133 (Dotsero) and 259 (C-470) carry chains at all times from September 1 to May 31. The new law now extends this requirement to commercial vehicles with a gross vehicle weight rating of 16,001 pounds or more, covering additional routes, including:

  • I-70 west of mile marker 259 (Morrison)
  • State Highway 9 from mile marker 63 to 97 (Frisco to Fairplay)
  • U.S. Route 40 west of mile marker 256 (Empire)
  • U.S. Route 50 west of mile marker 225 (Salida)
  • U.S. Route 160 west of mile marker 304 (Walsenburg)
  • U.S. Route 285 west of mile marker 250 (Morrison)
  • U.S. Route 550 — Entire route

Violating the chain law in Colorado can result in a $50 fine and a $17 surcharge.

Additionally, starting August 7, 2024, the new law prohibits commercial vehicles from driving in the far left lane of I-70 in certain areas unless passing is specifically allowed or required by law. These areas include:

  • Mile markers 115.5 to 131.0 (Glenwood Canyon)
  • Mile markers 169.5 to 173.0 (Dowd Junction)
  • Mile markers 180 to 190.5 (Vail Pass)
  • Mile markers 205.5 to 221.0 (Eisenhower-Johnson Tunnel)
  • Mile markers 224.0 to 228.5 (Georgetown Hill)
  • Mile markers 243.0 to 247.0 (Floyd Hill)