Christopher Ward, who served as executive director of the Port Authority of New York and New Jersey for three years, is widely credited with getting the $20 billion-plus rebuilding of the World Trade Center back on track after it slid over budget and behind schedule. Since stepping down from the huge public agency last year, Mr. Ward has rejoined the private sector, taking a senior position with the U.S. arm of Spanish construction firm Dragados. Mr. Ward is helping the company win major infrastructure contracts at a time when the New York region is rebuilding after Superstorm Sandy. In January, he started as head of the nonprofit Metropolitan Waterfront Alliance.