The modes of American transportation and its infrastructure transformed in order to accommodate the expansion of activities on the home front. Managing this transformation became the responsibility of reorganized federal agencies like the Civil Aeronautics Administration and the Office of Defense Transportation, who received critical assistance from private industry, as well as other agencies not accustomed to the work. While more advanced engines were put to use on new rail lines, roads were constructed and improved outside military installations across the southeast. Adding to the complexity of an already taxed transportation network, runway capacities at many airports increased to meet the demand. One of the many results of all this activity on the rails, land, and in the air was traffic congestion for individual citizens, who were often forced to alter their commuting schedules.