A joint venture between Tutor Perini and O&G Industries has been awarded a $1.2bn contract to design and build a 4km-long elevated railway at New Jersey’s Newark Liberty International Airport.

The “Guideway” will replace the AirTrain, which opened in 1996 and is now struggling to accommodate Newark’s growing passenger numbers.

The contract was awarded by the Port Authority of New York and New Jersey. Kevin O’Toole, Port Authority’s chairman, said: “As we work on a modern airport in Newark that will include new or expanded facilities, a reliable on-airport mass transit system will ensure that passengers and airport workers can get to where they need to go on a state-of-the-art system.”

Rick Cotton, Port Authority’s executive director, added: “Our major airports are the front doors of this region for the rest of the world, and ensuring easy, reliable public transit to and from the airport is critical.”

The Guideway is part of a larger expansion and upgrade to Newark that includes work on terminals, infrastructure, roads and taxiways. The airport’s Terminal A opened last year, replacing a 50-year-old building.

Construction is expected to begin on the Guideway next year and to complete in 2030.