Frequently Asked Questions


The I-70 East Project will be built in Phases. Work is currently underway on "Phase 1", also known as Central 70, that spans from I-25 to Chambers Road. "Phase 2" will eventually expand improvements to Tower Road. Phase 1 of the Project will:

  • Add one Express lane in each direction
  • Restripe from I-25 to Brighton Boulevard
  • Reconstruct I-70 from Brighton Boulevard to I-270
  • Widen from I-270 to Chambers Road
  • Remove the 57-year-old viaduct and lower the interstate
  • Construct a new 4-acre park over the interstate to reconnect the communities.

Revenue sources for the entire Central 70 Project include allocations from various sources, but there remains a gap between the estimated cost of the entire Project and the revenue available to build it. Because of the funding limitations, the Project will be constructed in phases over time. Phase 1 is the only defined phase for the Project at this time.

A Project being built in phases must: 

  • Connect logical termini (which is defined as rational endpoints for a transportation project and corresponding environmental review)
  • Be of sufficient length to address environmental matters on a broad scope
  • Have independent utility in that they would be usable and a reasonable expenditure even if no additional transportation improvements in the area are made
  • Not restrict the consideration of alternatives for other reasonably foreseeable transportation improvements.

We understand that Phase 1, or the current Central 70 Project, does not fully address all of the concerns in the I-225/Chambers Road area, however, we believe that the improvements being made with the current Central 70 Project will provide some relief. East of Quebec Street, Phase 1 will result in lower traffic volumes on the local street network. Phase 1 will also decrease westbound travel times on I-70 through the Project area by about 30% and eastbound travel times by about 50%. Once both Phase 1 and 2 are complete there will be greater time savings.

Phase 2 incorporates the remaining improvements needed to complete the entire Central 70 Project. This Phase would stripe in an additional tolled express lane from Brighton Boulevard to Quebec Street. Phase 1 constructed this section of I-70 wide enough to accommodate the additional lane.

From Quebec Street to Chambers Road, I-70 would be widened for an additional single lane in each direction, one going eastbound and one going westbound.

From Chambers Road to Tower Road, capacity is increased by widening to accommodate additional lanes. Three direct connections are included from the tolled express lanes to I-270, I-225, and Pena Boulevard to accommodate region and airport traffic. These direct connections result in a shift of eastbound I-70 to create room for the connections. 

Implementation of future phases may not occur if funding beyond the initial phase cannot be identified.

The Central 70 Project will:

  • Add one Express lane in each direction
  • Restripe between I-25 and Brighton Boulevard
  • Reconstruct I-70 between Brighton Boulevard and I-270
  • Widen between I-270 and Chambers Road
  • Remove the 57-year-old viaduct and lower the interstate
  • Construct a new four acre park over the interstate to reconnect the communities.

The purpose of the Central 70 Project is to implement a transportation solution that improves safety, access and mobility and addresses congestion on I-70.

The need for this Project results from the following issues:

  • Increased transportation demand
  • Limited transportation capacity
  • Safety concerns
  • Transportation infrastructure deficiencies
  • Reduced congestion and improved reliability on Denver’s most significant east-west corridor
  • Increase in Denver’s attractiveness as a place to do business
  • Aging infrastructure brought up to modern engineering standards

Traffic will be in final configuration by late 2022 with landscaping, installation of park elements and additional punch-list items continuing through 2023. 

This Project will cost $1.2 Billion, with contributions from Colorado Bridge Enterprise, Senate Bill 228, Denver Regional Council of Governments (DRCOG) and the City and County of Denver

  • Viaduct remains in place until 2021
  • Three lanes open in each direction on I-70 during rush hours
  • Limited number of full closures and major traffic switches on I-70
  • Programs/incentives to encourage carpooling and transit use
  • Coordinated on-ramp and cross street closures to maintain access

The park was a request of the neighborhood and is one of the many mitigations provided by the Project. The 4-acre park over the highway that will connect the Elyria-Swansea neighborhoods that were divided when the viaduct was built in the 1960s.

Yes, Kiewit Meridiam Partners and CDOT have teamed up for this Project. KMP will operate and maintain the highway for 30 years once the Project is completed. However, The High-Performance Transportation Enterprise (HPTE) will set the toll rates based on keeping the right amount of vehicles in the Express Lanes so travel times are reliable and CDOT will keep the tolls.

Express Lanes & Tolling

Adding an Express Lane can provide a level of travel reliability that a new general-purpose lane cannot; traffic on an Express Lane can be managed so vehicles are moving efficiently. Express Lanes on other highly traveled corridors in the state have proven to be successful in increasing roadway capacity, managing congestion, and providing travel choices, a reliable trip and improving travel times across all lanes.

To use any Colorado Express Lanes, you will need an ExpressToll account and pass to avoid a higher license plate toll. The Switchable HOV Transponder is the only pass that allows you to choose the carpool option and use the lanes for free if the driver has two or more passengers. Motorists can get a pass by visiting

Tolls will be determined as the Project nears completion.

Toll revenues will pay for the tolling equipment and installation, tolling operations and maintenance of the Express Lanes in the I-70 corridor to include snow plowing, debris removal and pavement repairs.

Travel Impacts

Decreasing traffic impacts is a top priority for CDOT. During construction, three lanes of traffic will be maintained in each direction on I-70 during peak travel times the vast majority of the time. Most lane and ramp closures will occur overnight, during non-rush times. Drivers will notice that lanes will be narrower and the interstate speed limit will be reduced.

During construction, motorists using the corridor may experience more delays than normal. Please check the latest information on road conditions before heading out. If necessary, allow some extra time to reach your destination. 

During construction, drivers are asked to stay on I-70, and avoid using local streets to bypass construction. You will not save time by detouring to local roads.

There will be utility work, ramp reconstruction and other construction activities that periodically affect roads connecting to I-70, but the bulk of the work is being done within the highway corridor. Highway lanes will be kept open during peak travel times to encourage drivers to stay on I-70 in lieu of seeking off-corridor detours, and with other local road improvement projects occurring simultaneously on some of the side streets, drivers will quickly learn that travel times won’t improve by avoiding the highway.

Interstate lane closures will be limited to nights and off-peak travel times whenever possible. A regular Safety Patrol will help move impaired vehicles quickly.

The Project team will coordinate with major events in the area and region, and work around-the-clock and on weekends (when needed) to deliver this Project on time, on budget and with as few impacts as possible.

Environmental Protections

Yes, CDOT conducted a comprehensive analysis of the air quality impacts of the Central 70 Project following guidance and protocols set by the US Environmental Protection Agency (EPA) and the Colorado Department of Public Health and Environment. This work, which accounts for the growth in traffic through the year 2040, has shown that the Project meets all national health-based air quality standards set by EPA. CDOT would not have received Federal approval for the Project without making this determination.

CDOT has provided an unprecedented level of public involvement tailored specifically to communities adjacent to I-70 in order to find ways to improve the Project and lessen its impacts. Through this process, the following specific and innovative commitments were developed:

  • Lowering the highway and providing a park with urban landscape adjacent to Swansea Elementary School.
  • Providing residents close to the highway construction with storm windows, furnace filters, attic insulation and two free portable or window-mounted air conditioning units
  • Providing $100,000 to facilitate access to fresh food
  • Providing an HVAC system and new doors and windows for Swansea Elementary School, plus two new additional classrooms
  • Providing $2 million in funding to support affordable housing in the Elyria-Swansea Neighborhood
  • Providing eligible residents of Globeville, Elyria and Swansea with free transponders, pre-loading of tolls or other means to reduce barriers to using the Express Lanes after the Project is completed


Yes, CDOT has examined options that would reroute portions of I-70 at many different junctures over the 15-year planning process. The concept of entirely moving a section of interstate that serves hundreds of thousands of commuters and freight vehicles every day is not a reasonable alternative nor is it one that would benefit local communities. At an estimated $3.2 billion cost, a reroute would result in significant traffic increases to the local street network and the construction of a major six-lane boulevard through Elyria and Swansea that would need to serve some of the region’s largest freight distribution centers.

Traffic forecasting for the Central 70 Project was done using the 2035 Denver Regional Council of Governments (DRCOG) trip-based travel demand model, which is the latest Compass model released by DRCOG. Compass is a regional model that applies projected land use data, including population and employment growth, to project future traffic conditions. This model incorporates household and employment data for the region and accounts for roadway and transit projects, including RTD’s commuter rail line (the A Line).

DRCOG owns and maintains this regional base model that incorporates every municipality within the DRCOG region, which includes the nine counties of Adams, Arapahoe, Boulder, Broomfield, Clear Creek, Denver, Douglas, Gilpin, Jefferson and the southwest portion of Weld County. Each alternative considered in the Final EIS was incorporated into DRCOG’s base model to determine future travel forecasts within the study area. These projections were used to determine the number of lanes needed for each alternative to accommodate future traffic growth.

In the more than 15 years spent planning this Project, the Colorado Department of Transportation and Federal Highway Administration looked into several alignment options for I-70 between I-25 and Tower Road. These alternatives, presented and refined during a series of public meetings and hearings, included several general-purpose and managed lane options for the section of highway between Brighton and Colorado boulevards along with options for rebuilding the viaduct in this section or removing it altogether and building I-70 below grade. This process yielded the preferred alternative – the partial cover lowered alternative – as the one with the most public support, the best in terms of improving safety and mobility, and the one that would restore and enhance the community while allowing Swansea Elementary to remain in its current location.