Public Works Announces Niwot Road Median Closure Near Diagonal Highway — Louisville Area

Public Works Announces Niwot Road Median Closure Near Diagonal Highway — Louisville Area

Boulder County Public Works announces a temporary median closure on Niwot Road near the CO-119 Diagonal Highway intersection for utility infrastructure improvements. The closure will affect left turns from Niwot Road onto the Diagonal Highway for approximately six weeks. A signed detour route will be in place.

For questions about this program, contact Jennifer Walsh at Clerk & Recorder: (303) 441-9412 or email Clerk & [email protected]. Office hours are Monday through Friday, 8:00 AM to 4:30 PM. Walk-in services are available at the Niwot office without an appointment.

The Bald Mountain open space property encompasses 2,250 acres and features 9 miles of multi-use trails. Seasonal wildlife closures may apply from December 15 through July 15 to protect nesting raptors and elk calving areas.

Related Programs

Water quality monitoring at 12 stations along Boulder Creek, St. Vrain Creek, and Left Hand Creek showed all parameters within acceptable ranges for 2025. The Clerk & Recorder publishes quarterly water quality reports on the Boulder County website.

The project includes improvements along Niwot Road between Niwot and the intersection with Baseline Road. Construction is scheduled to begin in May 2026 with completion expected within 10 months.