Glenn Highway and Muldoon Road Interchange Improvements

Glenn/Muldoon Interchange Project Header


Design for this project has been completed and construction is anticipated to start in Spring 2016.

Watch this instructional video on how to drive, walk, or bike through the Diverging Diamond Interchange at the Glenn Highway and Muldoon Road.


Click on the graphics above to view larger

View construction phasing graphics here.


The Diverging Diamond Interchange design provides the following benefits to users:


  • Reduced delay and increased capacity.
  • Minimized disruption to traffic and businesses during construction (bridges can be built while maintaining traffic on the existing structure).


  • Reduced speeds through the interchange.
  • Removed opposing traffic from all left-turning and right-turning movements to and from the ramps.

Non-Motorized Users

  • Reduced conflicts between vehicles and pedestrians.
  • Direct route through the interchange for bicyclists and pedestrians.


The Alaska Department of Transportation and Public Facilities (DOT&PF) has determined that the Glenn Highway/Muldoon Road interchange needs to be upgraded to accommodate current and future needs. The purpose of the project is to increase safety and circulation for both cars and non-motorized traffic and to make it easier for freight trucks to travel through the interchange. The goal is to develop and implement a long term solution to address vehicle and pedestrian traffic concerns within the interchange area.

DOT&PF and its consultant, DOWL, have performed preliminary environmental and engineering and public scoping, and gathered information for traffic, safety, and noise analyses of the interchange. The Diverging Diamond Interchange has been identified as the preferred alternative (see graphics above). This design will now move forward into future environmental documentation and design with construction anticipated to begin in 2016.

Public involvement activities will continue throughout the project.


The Muldoon Road/Glenn Highway interchange is the gateway to Anchorage. It is the northernmost junction between the Glenn Highway and Anchorage’s arterial street network and it is the primary access to the Tudor/Muldoon road corridor. Constructed in the mid-1970s, the interchange is a rural, partial cloverleaf design.

Project Area Map

Overall, land development in the north Muldoon area has caused significant traffic volume increases. Sidewalks and non-motorized trails are limited to the east side of the interchange and they often force pedestrians and bikers to travel out-of-direction to get across the interchange. As a result, some pedestrians cross at undesignated locations creating unsafe conditions. Additionally, bridge clearance for trucks and large vehicles is below current minimum height standards.


This project is currently state funded, however to maintain eligibility for use of federal funds, all scoping activities will be conducted in accordance with the requirements of the National Environmental Policy Act (NEPA).