Colorado Public Works Journal, Fall/Winter 2022

Fall/Winter 2022 61 RTD FASTRACKS Pauline Haberman Rail repairs at RTD’s 18th•Stout Station extend the life of the agency’s oldest light rail line The Regional Transportation District (RTD) recently completed repairs to a section of aging rail at its 18th•Stout Station in downtown Denver. The rail was installed 28 years ago as part of the D Line, or Central Corridor Line, which is RTD’s oldest operating line. Crews repaired a portion of rail at the station and an adjacent at-grade crossing that had experienced some settling due to heavy usage by an increasing amount of train and vehicular traffic. The downtown loop light rail line is “street running” with embedded track, so it shares numerous at-grade crossings with vehicles. Since the line opened on Oct. 7, 1994, vehicular loads have increased dramatically, not just in terms of traffic volume, but also in terms of overall weight. Construction vehicles, delivery vans and cars have become heavier, exacting an increasing toll on the roadway surface and track structure over time. At 18th•Stout Station, light rail train traffic has also dramatically increased. Tracks that initially carried just the D Line now also see trains for the H and L lines. In fact, over 200 trains travel through that point daily. The constant “poundings” gradually break down key track elements such as rail, ties, ballast and subgrade, eventually causing the rail to lose profile, or settle, in places. Because the track is embedded in the roadway, it is more difficult for crews to routinely maintain than track that is “open ballasted” (track where you can see the ballast and ties and can easily access them to conduct maintenance). When track must be replaced, RTD takes steps to replace the rail/vehicle crossings with more robust materials, such as concrete leveling slabs that provide increased subgrade stability, engineered precast concrete crossing panels instead of individual railroad ties, and approach slabs that transfer lateral loads to increase longevity and operational performance on the line. The author Pauline Haberman is Project Manager, Special Projects, Regional Transportation District and can be reached at The work to replace the section of rail at 18th•Stout Station required de-energizing the line from Wednesday, Oct. 12, through Tuesday, Oct. 18, so crews could remove track elements, then set new rails, ties, ballast, track panels and other elements, and pave and stripe the crossing. During the work, RTD suspended service on the D and H lines north of Theatre District•Convention Center Station and completely suspended L Line service. Customers were encouraged to use any of the multiple bus routes that serve the affected area, and refer to RTD’s Trip Planner and Next Ride web apps to plan trips in advance and see train and bus locations in real time. The project was successful thanks to extensive coordination among RTD, the contractor, KCI (Krische Construction Inc.) and the city of Denver, which worked together to complete the work on time despite the challenges of inclement weather and working alongside active downtown traffic. Regular service on the D, H and L lines resumed in time for the start of the service day on Wednesday, Oct. 19.