These projects consist of the replacement of cross ties, switch ties and ballast. In order to maintain proper track gauge and surface, it is necessary to replace ties and ballast periodically. This improves the riding quality of the trains and reduces the incidence of slow orders, which adversely affect adherence to train schedules. These projects represent part of an ongoing program to replace ties and ballast throughout the commuter territory. Projects on the Milwaukee District are split with the Canadian Pacific Railroad.