US 285 at Kings Valley

About the Project

This project will design a grade-separated interchange at US 285 and Kings Valley Drive located in Conifer, Colo. This interchange will consist of a typical diamond configuration for three legs of the interchange and a loop off/on-ramp for the fourth leg. Vehicles will travel beneath US 285 allowing them to enter and exit Kings Valley Drive without having to cross multiple lanes of traffic on US 285. This project will help with improving safety, performance, and operations at this intersection. 

CDOT Region 1 recognizes the US 285 and Kings Valley Drive Interchange Project as a regional priority and identifies the project as such in the CDOT 10-Year Plan. Please review the CDOT 10-Year Plan, Region 1 listing under “US 285 Improvements near Pine Junction” for more information.

Due to funding constraints, CDOT is ‘shelving’ the project at the Design Office Review (DOR) plan level (or 60%) until construction funding becomes available. CDOT is actively pursuing construction funding avenues, such as Federal Grants. Once construction funding is finalized, CDOT will continue the design process and construction can occur 12 to 18 months after design resumes.

Based on preliminary design, the interchange construction is expected to cost $70 million, with a total project cost of $77 million.

Project Area

The project is located at the US 285 and Kings Valley Drive intersection in Conifer, Colo. in Jefferson County.

Schedule & Important Dates

  • The project will be ‘shelved’ at the Design Office Review (or 60%) design level in the summer of 2025, due to construction funding constraints.
  • When construction funding is identified and encumbered, design will resume and take 12 to 18 months (this includes necessary Right-of-Way purchases) before construction can begin.
  • The construction schedule will become more finite once design resumes but is estimated to take two years to complete.
 Project Background

In 2002, CDOT completed a 53-mile-long feasibility study of the US 285 corridor from Foxton Road to Fairplay.  This study served to identify corridor needs based on future traffic volumes and patterns. The study identified a wide range of improvements, ranging from small, localized enhancements to major widening of segments. This plan was finalized in an Environmental Assessment (EA) in 2004 and concluded that US 285 should be widened to four lanes in addition to the following improvements:

  • Richmond Hill Interchange
  • Kings Valley Interchange
  • Shaffers Crossing / Elk Creek Interchange
  • Parker Road Interchange
  • Deer Creek Interchange
  • County Road (CR) 43A Interchange (by Developer)
  • Pine Junction Interchange
  • Mountain View Park-and-Ride Interchange
  • Crow Hill Runaway Truck Ramp

Since 2004, the improvements at Richmond Hill (completed in 2007), Deer Creek (completed in 2009) and Shaffers Crossing (completed in 2011), as well as widening between Foxton Road and Richmond Hill have been completed. These early phase improvements were selected due to the severity of the crash history at these locations.

The next improvement identified in the 2004 EA is to convert Kings Valley from an intersection to an interchange.

In late 2019 and during the re-evaluation effort, CDOT became aware of changed conditions at the project site since the completion of the 2004 EA.  These conditions included a historic property (i.e. Conley Coffee Shop), a historic district, and a conservation easement (Mountain Area Land Trust). Due to these changed conditions, an alternatives analysis was conducted in 2021 and identified an alternative that reduced impacts to historic properties while still meeting the overall purpose and need of the project. Design of this alternative has been in process since and is currently at the DOR (or 60%) design level.

 Project Benefits
  • This project will help improve safety at this intersection by reducing the number of conflict points, primarily Approach Turn and Head-on crashes. This will, in turn, reduce both the number and severity of future crashes.
  • The grade-separated interchange allows cars to turn left in and out of Kings Valley Drive by traveling beneath US 285, instead of crossing multiple lanes of traffic. This will help to improve safety and operations at this intersection.
  • The project will create safer multimodal connectivity for the community north and south of US 285. Existing conditions require crossing five lanes of traffic with no pedestrian connections or sidewalks.
  • The creation of a south frontage road and the relocation of the north frontage road will help to improve access, performance, and efficiency. The grade-separated crossing will facilitate an uninterrupted flow of traffic through this portion of the corridor.
  • The design of this interchange avoids historic structure impacts in the area.