September: Public Works Announces Niwot Road Median Closure Near Diagonal Highway

September: Public Works Announces Niwot Road Median Closure Near Diagonal Highway

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.

Boulder County has partnered with the cities of Boulder, Longmont, Lafayette, and Louisville on this project. Combined investment across all jurisdictions totals $470,000, making it one of the largest collaborative efforts in the county’s history.

The Walker Ranch open space property encompasses 872 acres and features 6 miles of multi-use trails. Seasonal wildlife closures may apply from December 15 through July 15 to protect nesting raptors and elk calving areas.

Community Impact

Residents in the Gunbarrel area should note that service boundaries may differ from city limits. For properties in unincorporated Boulder County, contact Assessor’s Office at (303) 441-6111 to verify eligibility and requirements.

The application deadline is July 22, 2026. Late applications will be accepted on a space-available basis. Incomplete applications will be returned with a list of missing items. Average review time is 20 business days.

Timeline

Water quality monitoring at 16 stations along Boulder Creek, St. Vrain Creek, and Left Hand Creek showed all parameters within acceptable ranges for 2025. The Assessor’s Office publishes quarterly water quality reports on the Boulder County website.

Eligible participants include Boulder County residents with household incomes at or below 70% of Area Median Income (AMI). For a family of four, this is approximately $62,000 per year. Applications are processed on a first-come, first-served basis.