Frequently Asked Questions

What is the latest with the Central 70 Project?

  • On January 19, 2016 the Federal Highway Administration providing final approval for the Central 70 Project. This approval (a Record of Decision) concludes the 14-year environmental study process and allows the project to move forward to construction. 

What does the Central 70 Project include?

The project is designed to improve the safety, mobility and community connections along one of Colorado’s most congested interstate segments. It will bring the infrastructure improvements to I-70 since this stretch of interstate was completed in the late 1960s. In the intervening years, usage of this highway has skyrocketed to nearly 200,000 vehicles daily.

These improvements include:
  • The addition of one new Express Lane in each direction from I-25 to Chambers Road.
  • Removal of the 50-year-old viaduct and lowering of the interstate between Brighton and Colorado boulevards.
  • Construction of a new, four-acre cover over the interstate between Clayton and Columbine streets.
    • This new, four-acre cover over I-70 is modeled after dozens of similar, successful public spaces over highways across the nation. CDOT is working closely with the City and County of Denver and local residents to design an active, thriving, year-round space to connect the neighborhood.
  • Project mitigations such as support for new low-income housing development and significant improvements to Swansea Elementary School.

When you say Express Lanes, what does that mean?

Express Lanes use tolls to manage congestion and keep travel times reliable for all motorists. Express Lanes will use a dynamic pricing system in which tolls can change in price depending on the level of congestion. As traffic increases, the toll price goes up, helping to keep you moving on the Express Lanes. Carpoolers and motorcyclists travel for free. These lanes are currently in place on I-25, US36 and the I-70 mountain corridor.

Is the lowered section a tunnel?

The highway between Brighton and Colorado boulevards (about 1.8 miles) will be built below ground level. It will look very similar to I-25 between Broadway and University Boulevard. However, there will be a 4-acre cover built over the highway for about three blocks of this lowered section – between Columbine and Clayton streets.

Has a ‘cover’ been added to other highways in the country or is CDOT the first to try this plan?

This is not a new idea. There are examples across the country over the past 60 years where covers have been added over freeways to form parks and join neighborhoods. Cities that have highway covers include New York, Seattle, Boston, Phoenix, Duluth and Dallas. St. Louis has one under construction and Los Angeles and Chicago have proposed a cover park over upcoming highway construction. As with any public space, the success of these covers relies on creating a safe, active and vibrant space. CDOT has partnered with the City of Denver, Swansea Elementary School, and local residents to design this cover. The City of Denver will have ultimate responsibility for programming and maintaining the space. View the most recent rendering of the cover.

What happens to 46th Avenue that currently runs under the viaduct?

46th Avenue will be rebuilt to carry traffic on both sides of I-70 and will remain at ground level. The street will be rebuilt to current city standards, including sidewalks and street lighting.

We’ve heard about this project for a long time. Is this really going to happen or is CDOT still studying options? What if we have a different idea for where this project should be built?

This project has been studied for 14 years and has involved one of the most extensive outreach processes in CDOT history. Multiple alternatives have been reviewed and analyzed and hundreds of public meetings have taken place. The preferred alternative has been selected based on a number of criteria and we are ready to move forward with actually building the highway. The final Record of Decision (ROD) from the Federal Highway Administration was issued on Jan. 19, 2017. Now that this has been issued, the developer selection will take place. Construction is expected to begin in 2018.

How long will this project take to build and when will it be complete?

Construction is scheduled to start in 2018 and it will take approximately four to five years to complete.

Does CDOT have a plan for drainage on Central 70?

Yes, the project includes a comprehensive and independent drainage system designed to handle a 100-year storm event. The Central 70 drainage plan addresses water from two sources: Water that falls directly into the lowered highway (known as the onsite system) and runoff from surface streets (the offsite system). Drainage Fact Sheet

Will CDOT be buying my property?

All questions on property acquisition should be directed to Tawana Kelly, the Central 70 CDOT Right-of-Way Manager at [email protected] or 303.757.9846.

How will traffic be managed during construction?

The final details of how traffic will be managed during construction will be determined by the developer, once they are selected. CDOT will require that the existing number of lanes on I-70 be maintained and open during construction except for very limited number of evening and weekend closures. It is expected that lanes will be narrowed and realigned as construction takes place, so some delays will occur. However, CDOT will be working with the Developer to develop programs that encourage carpooling, biking and use of RTD’s new A-line to help reduce construction delays.

How much will Central 70 cost to build? How will it be paid for?

The total estimated project cost for the Phase I Project is $1.17 billion.

  • Funding is provided through a variety of sources. See the list below.
  • There is no new tax increase required to construct the project.
  • Although a developer team will design, build, and help finance Central 70, the state will receive the tolls collected from the Express Lanes. The tolls are not part of the public-private partnership agreement with the winning developer team.
Source $ Amount
Colorado Bridge Enterprise Safety Surcharge $850 Million
Denver Regional Council of Governments $50 million
Senate Bill 09-228 Transfers $180 million
City and County of Denver $37 million


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