US 550–US 160 Connection South Project

Work this Week
May 8-14, 2022

US 160 Grandview Interchange Bridge Closed May 10 through Summer 2023

  • Alternate route for accessing south-side residences and businesses - including Target Rental, Skyway Auto and Durango Organics - will be the east and west intersections of County Road 232 at US 160 (please see link to map at left)

Bridge Closure Information: As part of the US 550-US 160 Connection South Project, the Colorado Department of Transportation and contractor Lawrence Construction will be closing the main Grandview Interchange bridge over US 160 on Monday, May 9. The bridge will remain closed through the summer of 2023. The closure of the bridge will facilitate safe excavation on the south side, where the new connection to US 550 is being constructed. Once material from the hillside is excavated, crews will remove a portion of the retaining wall. New walls will be constructed and the highway grade will be tied into the existing bridge.

About the Project

The Colorado Department of Transportation began construction of the US 550—US 160 Connection South in late summer 2020—the final phase of the project to complete the region’s first full interchange. CDOT will construct this project using the design-build process, partnering with a contracted team led by Lawrence Construction Company. 

The overall project scope involves constructing a new, 1.1 mile, four-lane section of US 550 north of La Plata County Road 220 to connect the major highway with the existing US 160 interchange, and widening a 3.3-mile section of US 550 south of CR 220 to four lanes, tying into the CR 302 intersection. 

Project Facts

  • Budget: $98.6 million
  • Contractor:
    Lawrence Construction Co. and RS&H, Inc.
  • Timeline: Summer 2020 to ummerS 2023
  • Location: US 550 & US 160 Interchange south of Durango, near Grandview and Three Springs

Current Construction Activities - Winter/Spring ‘21-’22

  • Earthwork, excavation of material north of CR 220
  • Complete roadway subgrade for new northbound alignment, CR 302 to US 160 interchange
  • Pave new northbound lanes (spring) 
  • Continue construction of the large and small mammal crossings
  • Continue placement of stormwater pipes

Please refer to Key Construction Steps, (left), for more detailed information.

Project Work Zone


The Design-Build Process

The design-build process is a two-step project delivery method where the design and build phases are combined into one contract. It represents a risk-sharing approach that assigns the inherent risks to the party that is best suited to mitigate, transfer or absorb those risks that are a part of any construction project. Design-build encourages innovation and efficiency to leverage the risks and add value to the contract.

Project Benefits

By realigning US 550 to connect with the US 160 interchange in Grandview, the project will greatly enhance safety for passenger and commercial vehicles, as well as cyclists. The new connection will eliminate the steep, curved grade of the current US 550. This realignment will greatly improve safety by creating a full-service, continuous-flow interchange that eliminates signalization and at-grade intersections (including that at the base of Farmington Hill) where crashes can occur. Safety will also be improved through the widening of US 550 to four lanes, with widened shoulders and auxiliary lanes for safer merges onto and off of the highway. Finally, the project will increase safety through wildlife underpass crossings and deer fencing, which will reduce animal-vehicle collisions.

Construction Impacts

  • From 6:30 a.m. to 6 p.m., Monday through Saturday (most weeks), motorists may encounter brief, intermittent stops near CR 220 and/or on the eastbound US 160 off-ramp just east of the US 550 junction for trucks entering/exiting work areas.
  • For weekly updates on specific traveler impacts, please see and choose the Interactive Map.