Caltrans quite clearly feels that stronger emphasis on the TCP is required. This comes from the state that was a pioneer in work zone safety practices. It is also from a state whose work zone traffic controls on Caltrans-administered highways are generally superior to those I have observed in most other states. The needed detail in the TCP depends on the complexity of the work and on the conflicts between traffic and the work. TCP should include provisions for adequate clearance between public traffic and work areas, work periods, and lane closures based on careful consideration of anticipated traffic volumes, and minimum exposure time of workers through simplified design and methods.
Early project planning for traffic control is very important.
This traffic control plan should include, but not be limited to, such items as signing, application and removal of pavement markings, construction scheduling, methods and devices for delineation and channelization, placement and maintenance of devices, roadway lighting, traffic regulations, and surveillance and inspection. The Traffic Manual provides that on portable concrete barriers the effect of impacting the ends of the barriers should be mitigated. Likewise, they may increase safety under such conditions. Caltrans states that most work zones can be divided into five areas as illustrated in Figure 1. The Manual provides a description of each of the elements.