Weir Gulch Channel Improvements and Decatur St Bridge

Project Overview

Weir Gulch Segment 1 is a key project in a high-priority basin to reduce flood risk to the Sun Valley neighborhood, increase pedestrian and bike mobility, promote natural habitat and increase recreation along this section of the gulch.This project is a partnership between Denver Parks and Recreation, the Mile High Flood District (MHFD) and the City and County of Denver.

The scope includes replacement of the existing concrete culvert at Decatur Street with a bridge and channel modifications along Weir Gulch from the South Platte River to 8th Avenue. The channel improvements will provide additional conveyance capacity while providing diverse plantings.  Redesign of the adjacent trails and sidewalks to increase mobility along the corridor is also included in the project.

 

Project Location

Weir Gulch near W 9th Ave & Decatur

Project rendering of the Weir Gulch project

 

Project Timeline

An infographic timeline of Weir Gulch Segment 1 Construction through 2026

Current Project Activities

  • Construction activities began on Monday, Oct. 20, 2025. As of January 2026, crews have:
    • Continued demolishing the north portion of the existing concrete box culvert east of Decatur Street.
    • Excavated dirt and materials west of Decatur Street to prepare the area for the future concrete drop structure.
    • Excavated the roadway and surrounding concrete on Decatur Street between Barberry Place and 9th Avenue.
  • As construction continues, crews will:
    • Continue demolition of the concrete box culverts and excavate the site.
    • Begin building the new bridge structure over Weir Gulch crossing Decatur Street.
    • Perform work on underground drainage systems and utilities. 

Decatur Street and 9th Avenue Closure

As of Thursday, Nov. 13, the 9th Avenue and Decatur Street intersection is closed. The road closure is necessary as crews will demolish the existing concrete culvert to facilitate construction of the new Decatur Street bridge and promote the natural habitat of Weir Gulch. Vehicles, pedestrians and cyclists will be detoured around the construction area. 

Weir Gulch Decatur Street Detour Map

 

RTD Bus Route 9 Detour

RTD Route 9 will be detoured to 8th Avenue and Federal Boulevard between the South Platte River and Federal Boulevard.

Trail Closure

As of Thursday, Nov. 13, the Weir Gulch Trail between 8th and 9th avenues from Federal Boulevard to the South Platte River Trail is closed as since it’s an active construction zone. 

Cyclists will be detoured to Hazel Court and the Lakewood Gulch Trail to access the South Platte River and Weir Gulch trails. The Weir Gulch Trail is open west of Federal Boulevard. Please visit Denver Parks and Recreation’s trail detours page for more information. 

Work Hours

Construction workdays and hours are anticipated to be Monday through Friday from 7 a.m. to 7 p.m. These hours could be adjusted for specialty work.

Heavy equipment may operate between the hours of 7 a.m. to 5 p.m. any day of the week. Material deliveries and staging may occur overnight. All project activities and schedules are weather dependent and subject to change.