US-285 & S Broadway Project

Project Overview

The US-285 & S. Broadway Interchange Reconstruction project will reconstruct the S. Broadway bridge over 285, the adjacent ramps, and US-285 itself from approximately Bannock St to Sherman St. The project will replace the aging and outdated bridge, improve roadway geometry, and improve pedestrian and bicycle facilities within the interchange.

Project Schedule

The design phase started in December of 2020 and was completed in early 2022. The project was initially advertised for construction in June of 2022 and the bid opening held on July 26, 2022. Due to unexpectedly high bids, construction cannot start until additional funding is identified for the project.

Proposed Improvements

Interchange Configuration

The consultant worked with the City and CDOT to develop and review possible interchange configurations. Ultimately, the analysis resulted in the recommendation and selection of a tight diamond interchange, similar to what exists today. Compared to the existing interchange, the proposed interchange will feature:

• Improved roadway geometry compared to the existing diamond
• Improved storage space for northbound left turning traffic
• Safer crossings with fewer conflicts between pedestrians and traffic at each crossing
• Provides more accessible greenspace by shifting the ramps closer to US-285
• Maintains a similar footprint which eliminates the need to acquire private right-of-way

Roadway Geometry Improvements

The new interchange will include 3 through lanes in each direction on US-285, while improving roadway geometry to meet modern standards for driver and pedestrian safety and comfort. The new interchange will modify the curve on US-285 to provide a more predictable and comfortable driver experience. The ramps will be designed to provide softer departure angles. The signalized intersection at US-285 & S. Sherman St will be removed to eliminate hazardous conflicts between US-285 traffic, S. Sherman traffic, and merging traffic to and from S. Broadway. The new geometry at Sherman St will only allow the option of traffic making a right turn from westbound US-285 to northbound Sherman St.

Bridge Replacement

The existing S Broadway bridge over US-285 is over 70 years old and does not meet modern design standards for roadways such as vertical clearances, appropriate lines of sights, and shoulders. This project will replace the outdated and deteriorating structure with a longer bridge to accommodate the additional lanes underneath. The bridge replacement gives the City the opportunity to improve on other sub-standard features on the S Broadway cross-section as well. Such improvements may include: an improved pedestrian and bicycle experience through wider sidewalks and a buffer zone between pedestrian and vehicle traffic, improved aesthetics on a keynote piece of infrastructure in the downtown district, and narrower lanes promoting safer driving as traffic enters the pedestrian dense downtown district.

Retaining Walls

As part of the bridge replacement the existing retaining walls will be removed. The new retaining walls will consist of short, cheap walls arranged in a stepped configuration to make up the elevation difference between US-285 & S. Broadway. In addition to a lower up front cost, these walls are easier to access and maintain, providing cost savings throughout the life-cycle of the new interchange.

Drainage

The additional lanes on US-285 will add more surface run-off that will need to be collected and responsibly discharged into the nearby Little Dry Creek. The proposed storm sewer system has a higher capacity than the existing system and incorporates storm water quality features including rain gardens and hydrodynamic separators.

Multi-Modal

The multi-modal improvements made through this project will be subtle, yet impactful. The types of bicycle and pedestrian facilities will remain primarily the same throughout the project, however, key changes will be made to improve the pedestrian and bicycle experience. The project incorporates the following characteristics to improve bicycle and pedestrian safety and comfort:

• Wider sidewalks on the S Broadway bridge
• Buffer zones between pedestrian and vehicle traffic wherever possible
• Improved overall aesthetic of the interchange
• Leading pedestrian intervals in the traffic signal phasing
• Roadway geometry that slows right turning traffic and provides higher pedestrian visibility
• Pedestrian refuge islands that shorten crossings and reduce the number of conflicts in a giving crosswalk

Aesthetic Improvements

The project will make significant changes to the visual characteristics of the interchange. The new bridge will incorporate prominent gateway features in the form of bookend columns with a large City of Englewood facing US-285 traffic. The bridge and retaining walls will feature colored and textured concrete to further draw attention to the city’s downtown district.

Project Funding

This project has three sources of funding. Federal funds awarded via a grant through the DRCOG Transportation Improvement Program, State Funds, and City of Englewood funds. The funding breakdown is as follows:

$7.6M (Federal Grant) + $3.1M (CDOT) + $4.2M (City of Englewood) = $14.9M