The Maryland Board of Publics Works on Wednesday unanimously approved a $60 million contract with Whiting-Turner Contracting Co. to expand the international terminal at Baltimore/Washington International Thurgood Marshall Airport.

The Baltimore Business Journal first reported that the project, slated to begin in the spring, will add 70,000 square feet to concourse E, which services BWI’s international flights, as well as renovate an existing 20,000 square feet.

The three-level development will…