West Alameda Bridge Replacement over South Platte River and Other Multi-Modal Improvements

• Replace the West Alameda Avenue bridge over the South Platte River
• Reconstruct South Lipan Street from West Alameda Avenue to the north where it ties into South Platte River Drive (the reconstruction will consist of one lane in each direction with a dedicated southbound left turn lane)
• Close South Platte River Drive north of West Alameda Avenue to West Cedar Avenue and remove the signal on Alameda Avenue
• Re-construct a portion of the South Platte River Greenway Trail
• Construct a cycle track on the north side of Alameda Avenue between South Kalamath Street and South Lipan Street
• Restore pedestrian and bicycle access on both sides of this heavily used corridor (all barriers preventing pedestrians and bicycles from using the south side of Alameda Avenue to cross between South Lipan Street and South Kalamath Street will be removed when construction is complete)
• Improve the intersection of West Alameda Avenue and South Kalamath Street
• Construct a water quality pond to the northeast of West Alameda Avenue and South Lipan Street intersection
• Add a new outfall in the South Platte River, from the proposed new water quality pond
• Modify the existing water quality pond to its ultimate capacity located to the south of West Alameda Avenue and west of I-25
• NOT included in this project currently, due to lack of funds and other potential options, is the West Alameda Avenue to northbound I-25 ramp
• West Alameda Avenue project map

• Improve safety for motorists, pedestrians, and bicyclists
• Improve connectivity to the South Platte River Greenway Trail
• Provide greater transportation options for the surrounding communities
• Optimize highway system operations and reduce congestion and delays

In 2006, an Environmental Statement (EIS) was completed for improvements to I-25 (Valley Highway) from Logan Street to US 6 and adjacent portions of South Santa Fe Drive and South Kalamath Street, plus West Alameda Avenue between South Lipan Street and South Kalamath Street.  The EIS was followed by a Record of Decision published in 2007.  The EIS process was used to develop, evaluate, and eliminate or advance potential alternatives for transportation improvements.  The EIS included the Preferred Alternative with the following major elements:

• I-25 Mainline: Widening of I-25 to provide a consistent section with four through lanes plus auxiliary lanes in each direction through the project area. (Complete).
• I-25/Broadway: Tight diamond interchange (The City and County of Denver has a current project to reconfigure the interchange. Construction is expected to start in Spring of 2022).
• I-25/Santa Fe Drive: Single point urban interchange with a flyover ramp for northbound Santa Fe Drive to northbound I-25 (Complete).
• US 6: Ramp improvements at I-25/US 6 interchange (Complete).
• I-25/Alameda: Offset partial urban interchange at I-25 and Alameda Ave (in development, excluding the Alameda to northbound I-25 on-ramp).

Preliminary design and a phased implementation plan for the overall interchange project were completed in 2008. Due to limited construction funding, it was planned that the project would be constructed in multiple phases.  Phase one was split into four smaller construction packages (titled Valley Highway EIS Phases 1.1 through 1.4) and are now complete.  This project, sometimes known as Valley Highway EIS Phase 2, had approximately 85% design plans and specifications completed in 2016. Phase 2.0 also included a ramp from West Alameda Avenue to northbound I-25, replacing the existing “Cedar” onramp to northbound I-25. There is not enough funding to construct the ramp in this project, but it will not be precluded by this project.  Furthermore, Valley Highway EIS Phases 3 and 4, which contemplate moving the BNSF Railroad from the current alignment to provide space for improved ramps and mainline I-25, may enable other options for providing an improved northbound on-ramp.  Phases 5 and 6 were improvements to US 6 and I-25, and they have been completed.

 I-25 Valley Highway Environmental Impact Statement (EIS) and ROD