Enhancing safety and mobility at a critical Commerce City intersection

For years, drivers, businesses, and neighbors have been asking the same question: When will something happen at 120th and US 85? While the final design and construction aren’t funded yet, this phase moves us closer than ever before. The Preliminary Engineering (PE) phase allows us to:

• Complete detailed designs
• Secure right-of-way
• Advance environmental approvals
• Strengthen future grant applications

In short: Preliminary Engineering lays the foundation for everything that comes next. Without it, the project can’t move forward.

The City of Commerce City—along with Adams County and the City of Brighton—is moving into the Preliminary Engineering (PE) phase for a new diverging diamond interchange and railroad overpass at 120th. This long-anticipated project aims to improve safety, reduce delays, and make travel more reliable for everyone.

This area has long been a bottleneck—trains, congestion, and safety issues have made getting through here a headache. The proposed solution includes:

• A diverging diamond interchange to improve traffic flow
• A bridge that will carry 120th over both US 85 and the Union Pacific Railroad
• Sidewalks and bike lanes for safer, more connected travel

These improvements will make it easier to get where you're going—whether that’s work, school, or the South Platte River Trail.