The Metropolitan Washington Airports Authority selected HNTB to design a loop tunnel system that allows automated people movers to link all the airport’s terminals and concourses.

The tunnel system was built under the airfield and would house an automated people mover that would shuttle passengers safely and efficiently between the airport’s three busiest terminals. The 10-mile, multitunnel project also accommodates a new baggage handling system, underground tugs, utilities, pedestrians and maintenance.

Based on the location of the tunnel segments, HNTB employed not one but three tunnel mining techniques. MWAA favored cut-and-cover construction for the tunnel segments, where access did not disrupt airfield operations. The New Austrian Tunneling Method and tunnel boring machines were used for burrowing under active taxiways and concourses.

HNTB led negotiation of the public-private partnership that extended the Washington, D.C., rail system to the Dulles Airport. The extension is part of a Washington Dulles improvement program designed to accommodate the region’s growing air travel needs.

•    Loop design allows APMs to link airport terminals, concourses
•    Some tunnels accommodate pedestrians and various airport operations
•    P3 leads to airport rail-service extension



Location: Washington, D.C.

Client: Metropolitan Washington Airports Authority