CO 14 Sterling S-Curve Study

Project completed

Project Overview

Three major Colorado highways intersect within downtown Sterling; US 6, CO 14 and CO 138 all enter the downtown core, and—using a network of two- and one-way streets—carry traffic east-west and north-south through the city. The existing highway configurations through town limit growth and development within the downtown core, lead to out-of-direction travel, and cause disruption from heavy truck traffic.

One concept to help alleviate downtown transportation issues is to direct large trucks moving east-west through town onto a bypass or "S-Curve" alignment that would use abandoned railroad rights-of-way between 4th Street/Chestnut and 5th Street/Division/West Main, completing a direct connection between CO 14 and US 6 in the east-west direction. This idea, along with the conversion of one-way to two-way streets, has been discussed for many years, and has been evaluated in detail in recent studies including:

  • 2011: Downtown Master Plan Concepts (Colorado Department of Local Affairs)
  • 2012: Downtown Sterling Roadway Conversion Report (CDOT & City of Sterling)
  • 2013: Sterling Master Plan Update (City of Sterling)

July Open House Recap

On July 27, 2017, CDOT hosted an open house for the Sterling S-Curve project at the Sterling Public Library. CDOT gave a presentation to summarize the current project status and update the public on the remaining design efforts and upcoming construction schedule. Additionally, the project team provided boards containing general information and design details for display throughout the meeting. Eighty-six people signed-in for the meeting. See a summary of the open house, including the presentation and comment forms.

Existing Conditions & S-Curve Design Concept

The following diagrams show the existing roadway network as compared to the S-Curve design concept.

Existing Roadway Network:

S-Curve Design Concept:

Design Update

Proposed Design Concept

Through input received at past public meetings, as well as a detailed screening process, a design configuration was developed for an S-Curve alignment. A set of screening criteria were developed which focused on regional mobility, improved operations, geometric design standards and magnitude of right-of-way impact. The screening process was reviewed with CDOT and the Town of Sterling to gather feedback and revise as necessary.

This project includes the following improvements:

  • Chestnut/4th Street: Right Turn only from existing northbound 4th onto Chestnut, and Right Turn only from westbound Chestnut/S-Curve to northbound 4th  will allow the removal of the existing traffic light here; stop signs and left through movement at Poplar Street
  • Chestnut/3rd Street: Signalized intersection with two 12-foot lanes each direction and left turn lanes onto Chestnut
  • 3rd/4th Streets: Conversion from one-way to two-way from South Division to Broadway, with 3rd Street becoming Highway 138.
  • South Division Street will be converted from a one-way to two-way between 3rd and 4th Streets and reconstructed to become Highway 6 north to West Main.
  • Intersection improvements will be made at 4th/Broadway and 3rd/Broadway/Sidney to accommodate the change from one-way travel to two-way roadways.

The proposed S-Curve configuration, as well as cross-sections of the S-Curve, South Division Street and Chestnut Street, are available by contacting the project team.

West Main Street Improvements

In addition to the improvements described above, West Main Street will be reconstructed from approximately 8th Avenue (tying into the recently completed reconstruction project) east to Division Street as shown below. Installation of raised medians, median lighting and drainage improvements along with ADA-compliant sidewalks and ramps are planned with the West Main Street reconstruction.

Colorado Highway 138 Repaving

As part of project construction, CDOT will complete a mill and overlay (repaving) of Colorado Highway 138 extending from approximately 2nd Street to just north of California Street.

Next Steps

As part of the initial phase of design option screening, a scan of environmental resources was completed, with a focus on the resources of most concern: Land Use, Socioeconomics, Right-of-Way, Historic Resources, Section 4(f), Biological, Hazardous Materials, Noise, and Air Quality. In compliance with the National Environmental Policy Act (NEPA), CDOT has initiated a Categorical Exclusion to evaluate these and other resources in greater detail.

Final design and right of way acquisition will proceed through 2017/2018. The project will be advertised in late 2018 and then construction will begin in the spring of 2019.  Public outreach will continue throughout the project.