County Line Road Closing for 100 Days, Major Safety Upgrades Planned

Drivers and residents who use County Line Road should plan now for a full closure of the roadway between University Boulevard and Broadway beginning Tuesday Jan. 6, 2026. Both directions of County Line Road will be closed between Clarkson Street and the U Haul business access for approximately 100 days, with the roadway expected to reopen in mid April 2026. Construction activity will generally occur Monday through Friday from 7 a.m. to 7 p.m., and Saturday work may occur with approval from Douglas County.

County officials said crews must close the road to safely import, move and place a very large volume of earth at Lee Gulch, an amount the project describes as equal to filling 40,000 washing machines. The fill operations will remove a dip at Lee Gulch to level the roadway, improving drainage, driver line of sight and public safety before paving and other finishing work proceed. Because of the scale of the earthwork, the roadway cannot safely support regular traffic during this phase and will remain closed during off hours even when crews are not actively working.

Access arrangements aim to preserve business and residential access while rerouting through traffic. Business access will remain open, with University Boulevard recommended for reaching businesses east of the closure and Broadway for businesses to the west. Residents will retain access to Clarkson Street via Dry Creek Road and County Line Road. Through trips should use C 470 between University Boulevard and Broadway to bypass the work zone. A detour map and project updates are available on the county project webpage.

The closure is one element of the County Line Road Widening and Reconstruction Project that began construction in September 2025. The $30 million effort, led by Douglas County in partnership with the City of Littleton, the City of Centennial and the Denver Regional Council of Governments, will add one travel lane in each direction, install a new traffic signal at Clarkson Street, mill and overlay pavement in the City of Littleton between Phillips Avenue and Broadway, and add new sidewalks. The overall project is slated for completion in September 2027.

For more information residents and businesses may call the project hotline at 720 795 9622 ext. 2523 or email [email protected]. Motorists are urged to follow posted detours, obey speed limits and exercise extra caution near the construction zone for the safety of workers and the community.