Viaduct Demolition - spring 2021 

As part of CDOT’s Central 70 Project, the 57-year old viaduct between Brighton and Colorado boulevards will be demolished to make space to build the future eastbound lanes of lowered I-70 and 46th South Avenue.

Demolition of the two-mile-long viaduct will be ongoing starting the weekend of May 21 through the summer of 2021.

Additional Information

  • Will and Will Not 
  • Viaduct Demolition 


The new lowered section lanes of westbound I-70 are wide enough to accommodate all six lanes of traffic. This is possible because we are expanding the highway’s width to accommodate one additional lane in each direction, and wider shoulders.

    A series of small lights will illuminate the lanes below. Once eastbound and westbound I-70 traffic is in its final configuration, more than 1,700 LED lights will be in place to help promote safety and prevent slow downs as traffic enters the tunnel. More than 80 of these lights will be used for emergency lighting and therefore will be on 24-7. In the instance of a power outage, there is a large generator that will turn on to ensure there will always be lighting in the tunnel, no matter the circumstance.

    Motorists should be prepared for the potential of slower traffic while entering the lowered section as folks become adjusted to the new environment. The lowered section, and tunnel in particular, is intentionally designed to allow for normal flow of traffic without encouraging slower traffic. CDOT strongly suggests motorists to continue flowing at a normal speed through the lowered section to prevent crashes or unnecessary congestion.

    Motorists can expect to be in this configuration for about 18 months, until the future eastbound lanes of I-70 are complete.

    The speed limit on I-70 between Brighton Boulevard and Chambers road will remain at 55 mph. 

    The drainage on the cover park is a unique element of this robust system on the Project. As the water falls onto the cover park, it is allowed to seep down through multiple layers before it is collected in an impervious layer just above the concrete bridge deck. It is then channeled into pipes on the north and south side of the park before making its way to the pump station with other stormwater. This stops ponding in the park while preventing water from leaking down onto the highway below.