Project Elements

Express Lanes

Express Lanes increase roadway capacity and help manage congestion on highways. Ultimately, they provide drivers the freedom of choice—whether they choose to ride the bus, carpool or pay a toll.

Visit our Express Lanes web page for more information on Express Lanes in Colorado.

Express Lanes provide multiple options of getting to your destination (in addition to free, general-purpose lanes) while also providing the great advantage of improving trip reliability in a region experiencing rapid growth, development and congestion.

The North I-25 Express Lanes project will add capacity to the existing roadway by providing one new express lane in each direction with a painted buffer separating it from the three free general-purpose lanes. The Express Lanes will operate 24 hours a day, 7 days a week, and toll rates will fluctuate depending on the amount of traffic using the Express Lanes so traffic can operate at free-flow conditions. Automatic collection points will be located between each major interchange for each direction of travel.

Intelligent Transportation Systems equipment will be installed and integrated with the Express Lanes project, previously constructed on I-25 from US 36 to 120th Avenue. Users will be able to choose to take the Express Lanes from downtown Denver to north of 120th Avenue.

An operations system will include loop detectors, variable message signs, real-time digital video cameras, toll-collection and process units, and enforcement equipment to collect traffic data, disseminate real-time travel and pricing information to drivers, and support enforcement.

The High Performance Transportation Enterprise (HPTE) is pursuing a contract with the E-470 Public Highway Authority for toll collection, processing, customer service and other back-office needs.

Express Bus/Transit/Carpooling

Patrons of existing and future Park-and-Ride facilities, and Bustang, the new regional bus service from Northern Colorado to Denver Union Station, can use the Express Lanes system for a faster, more reliable trip. The project will also construct a bus and HOV bypass at the southbound 120th Avenue on-ramp, allowing for the implementation of ramp metering. This will increase the operational function of North I-25 and improve safety on the corridor.

Roadway Improvements

The project will widen I-25 to the outside, maximizing the use of existing infrastructure. The entire asphalt section of the roadway within the project limits will be repaved, providing improved skid resistance and drivability, new pavement markings, signage and delineation. A safety edge will be added to the new pavement to eliminate pavement edge drop offs.

Retaining and Noise Walls

Crews will construct approximately 3,000 feet of retaining wall along the corridor to minimize impacts to right-of-way, open space, new development, parkland (Section 4(f)) and wetland areas. Nearly 5,000 feet of noise walls will be constructed, including:

  • 1,850 feet of 14-foot high noise wall at Thorncreek Village
  • 1,100 feet of 12-foot high noise wall at the Tanglewood multifamily development
  • replacement of a deteriorating wood noise wall with a new 2,000-foot wall adjacent to the residential properties south of the existing Bus Tunnel (SW quadrant of 120th Avenue interchange)
    The proposed new wall will be concrete, which is a more effective sound barrier, aesthetically pleasing, and provides corridor continuity with the project to the south.

Drainage and Water Quality

The project will provide water quality treatment for the corridor in accordance with CDOT's new MS4 permit. Primary treatment includes four water-quality ponds along with a 4-foot-wide natural-lined ditch system to convey highway runoff to the ponds.