Duluth International Airport’s (DLH) concrete Runway 9/27 was in excess of 60 years old and had deteriorated to the point of warranting a complete reconstruction. However, there were challenges for the Duluth Airport Authority (DAA) to overcome during construction in order for key airline traffic, businesses and organizations to remain in use. A thoughtful and innovative construction phasing plan was needed to ensure they were not impacted by closure and reconstruction of Runway 9/27.
Specifically, in addition to commercial air service provided by Delta Air Lines and United Airlines, as well as corporate and general aviation traffic, the 148th Fighter Wing of the Minnesota National Guard is based at DLH and flies their F-16 fighter jets at the airfield. During construction and closures to Runway 9/27, a large portion of aircraft using DLH could operate on the shorter crosswind Runway 3/21. The F-16s required a longer runway length and would essentially become grounded if Runway 9/27 were to close. Closing Runway 9/27 would also impact businesses on the airfield – including the Fixed Base Operator (FBO) which serves large business and military aircraft, requiring a longer runway length. An aircraft maintenance facility on the airfield would also be impacted by closing Runway 9/27, as their primary customer flies Airbus 319 and 320 commercial service aircraft. Due to company risk management standards, those aircraft could also not utilize the shorter Runway 3/21.
In addition, the existing airfield geometry on and around the end of Runway 9/27 did not meet Federal Aviation Administration (FAA) standards and included two “Hot Spots” – that is, areas on the airfield where pilots can potentially lose situational awareness. FAA requirements call for the geometry in this to be redesigned as part of the Runway 9/27 reconstruction effort.
The DAA sought the expertise of SEH’s Airport Planning and Design group to facilitate reconstruction of the runway and reconfiguration of the end of Runway 9/27. In order to minimize the impacts to the National Guard’s fighter jet operations, traveling public and organizations noted above, the SEH team’s efforts on the project involved developing and implementing a complex, three-phrase construction plan.
- Phase 1 – Center 6,200 feet of runway
- Phase 2 – Western 2,000 feet of runway
- Phase 3 – Eastern 2,00 feet of runway
Phase 1, which reconstructed the critical center section of Runway 9/27 required complete runway closure. In close collaboration with the DAA, SEH worked with the 148th Fighter Wing to coordinate the reconstruction of a portion of the center section while the Fighter Wing was already scheduled for an extended deployment. The remainder of work done on the center section was coordinated in advance with leadership from the Fighter Wing to enable the F-16s to temporarily relocate during construction.
For the two other phases, which involved reconstruction of approximately 2,000 feet of runway on each of the runway ends, SEH’s planning and design team implemented the following tactics to minimize impacts to airfield operations:
- Displaced threshold operations, which involved shortening the runway to remain open while reconstruction took on the closed portion
- The available runway length in these phases was designed specifically to meet the needs of the 148th Fighter Wing and commercial airliner traffic
- Night closures to accommodate construction work in critical areas of the airport
- 24-hour construction for specific work elements to expedite reopening of the runway
A specific challenge for the third phase of the project, the reconstruction of the eastern end of the runway, was reconfiguring the runway geometry in order to meet FAA design standards. In order to do this, the SEH undertook a fast-paced planning study to identify potential solutions to eliminate problematic intersections, improve taxiway geometry and meet FAA standards and guidance. The study included substantial communication with key stakeholders to obtain feedback on the upcoming airfield changes in order to ensure all concerns were addressed.
The planning study ultimately identified a solution that included the relocation of the end of Runway 9/27 and threshold as a key element of the geometry improvements completed as part of the third phase. The SEH team’s planning effort also included updating the Airport Layout Plan (ALP) to show proposed geometry improvements, Airports GIS and initiation of new instrument flight procedures to the relocated runway end.
The three-phased runway reconstruction effort included a collaborative process with the FAA, Minnesota Department of Transportation Office of Aeronautics, airport staff, airfield tenants and users and other stakeholders. SEH also developed and implemented a robust public outreach effort, including tools like the following to provide ongoing education and information around the project’s status and impact:
- Neighborhood notifications
- Construction flyers
- Electronic weekly newsletters
- Website updates
- Press releases
- Construction tenant working groups
- Weekly tenant call-in meetings
The three phases of reconstruction effort included removing the two-mile long Runway 9/27 and replacing it with improved base materials and 13-inch concrete pavement. Additionally, portions of the adjacent Runway 3/21 where the two runways intersected were also reconstructed, eliminating the need for Runway 9/27 to close for future reconstruction efforts of Runway 3/21. For comparison of size of the reconstruction effort, the two miles of runway pavement repaired during the reconstruction is equivalent to more than 24 miles of highway.
SEH's efforts on the project also included many electrical improvements including new in-pavement runway centerline lighting, touchdown zone lighting and edge lighting. The lighting improvements included the installation of approximately 500 LED lights and nearly 40 miles of electrical cable. The Runway 27 in-pavement MALSR threshold bar lights were relocated and coordinated through an FAA reimbursable agreement. The SEH team also installed Precision Approach Path Indicator (PAPI) lights on the west end of the runway. These lights provide visual guidance for pilots to safely land their aircraft. To control everything, a new Airfield Lighting Control Management System (ALCMS) was installed, allowing lighting control and communication from the Air Traffic Control Tower (ATCT) to the runways and taxiways.
As part of the overall project, the DAA and SEH design team worked with the 148th Fighter Wing to remove and replace aging military arresting gear equipment. This equipment provides a cable system across the runway to quickly and safely stop landing F-16 aircraft. Coordinating this work with the planned runway closure of the center section of the runway eliminated future impacts to the runway.
The FAA provided funding for 90 percent of the total costs of the project. For the remaining 10 percent local share, SEH helped secure $6.6 million from the State Legislature through a direct appropriation to the State Airport Fund to be used exclusively on Duluth Airport Authority projects.
Collaborative long-term planning and creative design solutions combined with stakeholder outreach and engagement made this runway reconstruction project successful. The new runway is set to serve Duluth, Northeast Minnesota, Northwest Wisconsin and the 148th Fighter Wing for the next 50 years.
- 2020 Honor Award | American Council of Engineering Companies, Minnesota Chapter (ACEC-MN)
Runway 9/27 Reconstruction, Duluth International Airport
City of Duluth, Minnesota
Duluth Airport Authority
- Triggering Event Master Plan study
- Two miles of reconstructed runway
- Relocated runway end and threshold
- Instrument approach procedure development
- 200,000 square yards of concrete
- Electrical improvements including installation of approximately 500 runway lights and nearly 40 miles of electrical cable
- Airfield signage and markings
- Airfield Lighting Control Management System
- Military arresting gear
- Obstruction removal
- Relocation of taxiway connector
- Airport planning
- Project design
- Environmental review
- Wetland delineation and permitting
- Civil engineering
- Construction administration
- Funding acquisition assistance and support
- Public outreach and stakeholder engagement