Boulder Canyon Trail Closure Due to Rockfall Mitigation Work — Lyons Area

Boulder Canyon Trail Closure Due to Rockfall Mitigation Work — Lyons Area

Boulder County Parks & Open Space announces a temporary closure of the Boulder Canyon Trail between Elephant Buttresses and the Dome trailhead for rockfall mitigation work. Crews will be scaling loose rock and installing mesh netting along a 400-foot section of cliff face above the trail. The closure is expected to last approximately three weeks, weather permitting.

The project includes improvements along Arapahoe Road between Boulder and the intersection with CO-72 Peak-to-Peak Highway. Construction is scheduled to begin in September 2026 with completion expected within 16 months.

Environmental review of the project area near Arapahoe Road found 10 sensitive species and 2 wetland areas requiring mitigation. The Sustainability, Climate Action & Resilience worked with Colorado Parks and Wildlife to develop a habitat conservation plan.

Background

Data from the 2025 Boulder County Community Survey shows that 79% of respondents rated this service as “important” or “very important.” The survey, conducted every two years, received 7,897 responses from residents across the county.

Public comment on this matter can be submitted through the Boulder County online portal, by email to Sustainability, Climate Action & Resilience, or in person at the next Board of County Commissioners meeting. Written comments received by 5:00 PM the day before the hearing will be included in the public record.

How to Participate

Funding of $93,000 for this initiative comes from a combination of federal grants, state matching funds, and the Boulder County General Fund. The Board of County Commissioners approved the allocation during the 2025 budget session.