Project Profile: I-225 ‘R Line’ Light Rail Transit, Denver

The Interstate-225 (I-225) Rail Line, officially designated the R Line, is an 11.2-mile light rail transit (LRT) system enhancing connectivity between the key metropolitan hubs of Denver and Aurora, Colorado. Developed as a critical component of the Regional Transportation District’s (RTD) FasTracks program, the project involved complex civil and electrical engineering within the I-225 highway median to establish a vital commuter link serving major employment centers, including the Anschutz Medical Campus.

Technical Specifications

The R Line’s alignment is predominantly located within the median of the I-225 highway, a design choice that required intricate phasing to minimize disruption to existing traffic flows. The project’s civil engineering scope included the construction of eight new stations, multiple bridges, and the complex reconstruction of the Yale Bridge to accommodate both highway expansion and the new double-track light rail system. Integration with existing infrastructure was critical, particularly at the Nine Mile station, demanding precise planning to merge new and old segments of the network seamlessly.

The line is powered by a robust 825V DC overhead catenary system. Electrical infrastructure includes 11 traction power substations strategically placed along the corridor to ensure consistent power delivery to the rolling stock. The fleet consists of double-ended light rail vehicles, providing operational flexibility and efficiency. A modern communications backbone, utilizing fiber optic cables, connects the line’s systems—including CCTV, public address systems, and Variable Message Signs (VMS)—to a central operations control center for real-time monitoring and management.

Key Takeaways

• Integrated Infrastructure Development: The project exemplifies successful co-development of rail and highway infrastructure, with the rail line construction coordinated with the Colorado Department of Transportation (CDoT) to optimize resource utilization and public investment.
• Enhanced Regional Connectivity: By linking key destinations such as the Aurora City Centre and the Anschutz/Fitzsimons Medical Center, the R Line serves as a critical north-south spine in the regional transit network, alleviating traffic congestion and improving access to major employment hubs.
• Effective Project Delivery Model: The project’s success, initiated from an unsolicited proposal by Kiewit Infrastructure, highlights the effectiveness of collaborative partnerships between public agencies like RTD and experienced private engineering and construction firms.

Frequently Asked Questions (FAQ)

When did the Denver R Line open?

The Denver R Line, also known as the I-225 Rail Line, officially began passenger service in February 2017.

Who built the I-225 Rail Line?

The I-225 Rail Line was developed by the Regional Transportation District (RTD) with Kiewit Infrastructure serving as the primary construction contractor. Key partners included AECOM for engineering and design, SEMA Construction, and the Colorado Department of Transportation (CDoT).