Construction Begins Sept. 28 on 21st Avenue for Railroad Quiet Zone Improvements - City of Longmont
Advisory

Beginning Sept. 2, the Development Services Center (385 Kimbark St) will be closed to the public every Wed, 8 – 11 am.

Construction Begins Sept. 28 on 21st Avenue for Railroad Quiet Zone Improvements

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

September 21, 2026 – The City of Longmont will begin construction at the 21st Avenue railroad crossing on Monday, Sept. 28, as part of the Railroad Crossing Safety Improvements (Quiet Zones) Project.

 

Construction is expected to continue in two phases through mid-November. The railroad crossing will be fully closed to vehicles during each phase but will reopen for about 24 days between phases. The pedestrian crossing on the north side of 21st Avenue will remain closed throughout construction.

 

Note: Trains will remain active on the railroad tracks throughout construction.

Phase 1 full closure:

Sept. 28 through approximately Oct. 9

The railroad crossing will be fully closed to vehicles while crews work on drainage improvements and construct curbs and medians.

 

    • Drivers will be detoured to Collyer Street, 17th Avenue and Alpine Street.
    • The pedestrian crossing on the north side of 21st Avenue will be closed. Pedestrians will need to cross 21st Avenue at Meadow Drive or Olympia Avenue and use the temporary sidewalk on the south side to cross the railroad tracks.

Temporary reopening

Approximately Oct. 10 through Nov. 2

The railroad crossing is expected to reopen to vehicles from Oct. 10 through Nov. 2. The pedestrian crossing on the north side of 21st Avenue will remain closed during this period.

 

Phase 2 full closure:

Scheduled for Nov. 3 through Nov. 24

The railroad crossing will fully close to vehicles again for approximately three weeks while BNSF completes railroad safety improvements and crews construct sidewalks.

    • Drivers will again be detoured to Collyer Street, 17th Avenue and Alpine Street.
    • The pedestrian crossing on the north side of 21st Avenue will remain closed through mid-November. Pedestrians will continue to use the temporary sidewalk on the south side of 21st Avenue to cross the railroad tracks.

 

Dates are approximate and may change due to weather, BNSF coordination or unexpected construction conditions.

Construction hours:

Monday through Friday from 7 am to 5 pm, with some weekend work as needed.

 

Quiet Zone Designation:

Construction of the required safety improvements does not automatically establish a Quiet Zone. Once improvements are complete, the City must submit documentation to the Federal Railroad Administration (FRA) for approval. The 21st Avenue crossing is expected to become part of a Quiet Zone 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.