21st Avenue Railroad Crossing to Close Oct. 28 for Approximately Three Weeks - City of Longmont
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21st Avenue Railroad Crossing to Close Oct. 28 for Approximately Three Weeks

Orange Train crossing Longs Peak Avenue in Longmont with green trees in the background under a blue sky.

October 26, 2026 – The City of Longmont will begin Phase 2 construction at the 21st Avenue railroad crossing on Wednesday, Oct. 28, requiring a full closure of 21st Avenue at the railroad tracks for approximately three weeks. The closure is part of the Railroad Crossing Safety Improvements (Quiet Zones) Project.

 

During this phase, BNSF Railway will complete railroad safety improvements, and construction crews will construct sidewalks.

 

Drivers must use alternate routes before reaching the railroad crossing. There is no through access on 21st Avenue, and nearby residential streets do not provide a way around the closure.

 

Detour Routes

  • Eastbound on 21st Avenue: Local traffic only past Collyer Street. All other drivers should turn onto Collyer Street and travel south to 17th Avenue or north to Highway 66. There is NO outlet through the Villas at Park Crest neighborhood east of Estes Lane. Commuters who continue toward the railroad tracks will have to turn around and return to Collyer Street.
  • Westbound on 21st Avenue: Drivers should use Alpine Street to reach 17th Avenue or Highway 66. Other neighborhood streets such as Mt. Sneffels will remain open but Alpine St. is the recommended detour.

Motorists are encouraged to plan ahead, allow extra travel time and follow posted detour signs. Local access will be maintained on either side of the railroad crossing, but vehicles will not be able to cross the tracks.

 

Pedestrian Access and Construction Information

The pedestrian crossing on the north side of 21st Avenue will remain closed. Pedestrians should use the temporary sidewalk on the south side of 21st Avenue to cross the railroad tracks.

 

Construction Hours

Work will occur Monday through Friday, 7 am to 5 pm, with some weekend work as needed. The closure is expected to last approximately three weeks, but dates may change due to weather, BNSF coordination or unexpected construction conditions. Trains will remain active throughout construction.

 

About the Quiet Zone Project

The improvements at 21st Avenue are part of the City’s effort to enhance safety at railroad crossings and establish Quiet Zones, where trains are generally not required to sound their horns during routine operations.

Completion of construction does not automatically establish a Quiet Zone. The City must submit documentation to the Federal Railroad Administration (FRA) for approval. Train horns are expected to stop at the 21st Avenue crossing in summer 2027.

 

For the latest construction information, visit the Group 2 Quiet Zones project webpage. Questions or concerns can be directed to the project hotline at 720-526-2044 or QuietZones@longmontcolorado.gov.