Sugarloaf Road Boulder, Colorado

Following historic flooding in Colorado, repairs to Sugarloaf Road went beyond correcting existing issues to include several enhancements. The Otak design added a bikeable shoulder and drainage plans, altogether enhancing resilience and active transportation infrastructure for Boulder County communities.

A Roadway Designed for Flood Recovery, Resilience, and Active Transportation

Failed retaining walls along Sugarloaf Road during historic flooding required immediate repair guidance. As part of an overarching FEMA-administered Flood Recovery Program, the final design not only corrected drainage issues that caused wall failures and debris to enter the roadway but also allowed the new wall and drainage design to provide for an uphill climbing bikeable shoulder for known heavy bicycle traffic to the area. Three-tier gravity retaining walls and mechanically stabilized earth (MSE) walls were used to create a wider roadway that accommodates these enhancements. Working closely with county staff and with input from public outreach, several wall options were presented that intended to blend in with the natural environment, while ensuring it was constructible, in compliance with various permitting, and maintainable for years to come. Expedited delivery of this project included initial work to develop a temporary retaining wall to fully open the roadway to the public until completion.