RTD downtown Denver rail work starts June 7, suspending three lines

Denver rail riders heading downtown should plan for changes starting Sunday, June 7. RTD says the next phase of its Downtown Rail Reconstruction Project begins that day and is expected to continue through the first quarter of 2027 as crews replace aging track on Colfax Avenue and in the Downtown Loop.

The agency says the work is part of a multi-year project to rebuild its oldest rail assets. RTD says the downtown track network has served the central corridor for more than 30 years, and the full-depth reconstruction is meant to improve safety and reliability.

Which lines are changing

RTD says D, H and L line service through the affected downtown area will be suspended. To keep riders moving, the agency plans to use the C Line, a temporary T Line and bus alternatives.

For D Line riders, RTD will restore C Line service between Littleton•Mineral Station and Denver Union Station, with connections to the Downtown Loop using the 16th Street FreeRide or Free MetroRide. H Line riders will use the temporary T Line between Lincoln Station and I-25•Broadway Station, while L Line riders will rely on Route 43 and alternate bus service on Colfax.

Why it matters downtown

RTD says the work covers track along Colfax Avenue between Seventh and Ninth streets and midblock sections in the Downtown Loop. The agency says no full closures are planned in the loop, but traffic may be merged to one lane.

That means more planning for commuters, downtown workers and event-goers who usually depend on D, H or L line trips into the central business district. Nearby businesses may also see changes in access and foot traffic while construction is underway.

What riders should watch next

RTD says bus Route 16 and Route ART will continue to serve the Colfax at Auraria area, and bus stops near the project should remain open. Riders are being told to check RTD trip tools and service alerts before traveling downtown.

For now, the key date is June 7. Anyone traveling through downtown Denver by rail should expect detours, transfers and possible delays as the reconstruction phase begins.

Sources

• RTD news release: Downtown rail reconstruction phase begins in June
• CBS Colorado report on Colfax rail reconstruction near Auraria Campus