Complex Engineering and Construction Phasing at One of the Busiest Airports in the U.S.

Since 2021, HDR’s team has been working on a multi-year project to improve capacity and enhance safety on the north airfield at Ronald Reagan Washington National Airport (DCA). 

The north airfield at DCA had problematic geometry and physical limitations that contribute to congestion at the airport. Addressing these involves the realignment of multiple taxiways and expansion of a runway hold bay, as well as pavement and lighting changes to address an airfield hot spot. The overall program, consisting of three packages of projects, has an estimated construction cost of $185 million.

HDR provided conceptual, preliminary, and final engineering design for the whole program. Our work has included civil, electrical, mechanical, structural, environmental and geotechnical engineering, as well as architecture for a new airfield lighting vault and security checkpoint shelter. Following groundbreaking, we are also supporting the Metropolitan Washington Airports Authority (MWAA) with construction administration services. 

Keeping Airport Operations Running

One of the large hub airports in the United States, DCA welcomes more than 20 million passengers a year and has over 800 daily aircraft operations. But while peer airports with similar traffic average about 5,000 acres, DCA is on just about 730 acres, a very constrained site.

Working around these very busy operations and designing construction phasing options to minimize the impact has been a major goal of the project. This is a tremendous challenge when pavements require full depth reconstruction. To overcome this challenge, the project’s sequencing approach constructs as much of the new pavements possible before disrupting the existing pavements. This allows for additional aircraft routing options. 

In addition, construction phasing uses off-peak nighttime construction. Restrictions associated with the off-peak construction were worked out during extensive workshops with the various stakeholders including MWAA Engineering, Operations, and Maintenance, in addition to the airlines and FAA. The project area was divided into more than 50 individual work areas, each with its own schedule restrictions and plan for closures, gate access restrictions and restoration requirements. In some areas, closures were limited to a maximum of a five-hour nightly closure, with complete restoration required upon completion of each shift, allowing aircraft traffic to operate without disruption. 

Geotechnical Solutions

Another main challenge on the program is the geotechnical characteristics of the airfield, given its proximity to the Potomac River. Much of the airport, including the north airfield, was originally built on mudflats in the river. As a result, the design had to consider and remediate the challenging alluvial soils. 

A variety of improvements and solutions were used to address the settlement expected with the soft, fine-grained soils beneath the airfield. Surcharging, preloading, weight neutral, and wick drains were all employed, depending on operational need and site-specific ground conditions. 

A Project of Multiple Parts

The North Airfield Improvement project includes three separate bid packages: 

• Package 1 included site preparation, utility work, a new airfield lighting vault, and a new security checkpoint. It completed construction in September 2026. 
• Package 2 consists of the majority of the airfield paving and lighting work and is anticipated to begin construction in fall 2026, concluding in late 2028.
• Package 3 included rehabilitation of Taxiways J and K. Construction was completed in August 2026. 

Altogether, the project and its packages will require 75,000 tons of asphalt, more than 50,000 square yards of concrete, 2 miles of new drainage pipe and 95 miles of electrical duct bank cabling.