A review of city traffic control programs for construction and maintenance work zones

The purpose of this study was to evaluate the present stateof-the-art of city traffic control programs for construction and maintenance work zones. Information was gathered using two separate investigations to determine (l) the status of present city construction and maintenance work zone traffic control programs and (2) the effectiveness of these programs.

A survey was conducted by sending questionnaires to one hundred cities in the United States asking for information related to various aspects of the cities' work zone traffic control programs. Forty-nine cities returned questionnaires and, based on their responses, they were rated according to their degree of involvement in regulating work zone traffic controls. The results indicated that (1) there is a wide variation in the amount of importance cities place in work zone traffic control programs and (2) the majority of the cities surveyed do a less than adequate job in controlling construction and maintenance activity.

Thirty field investigations of construction or utility work zones in eight of the surveyed cities were studied to evaluate the effectiveness of the cities' work zone traffic control programs. Using a modification of a rating formula developed for a previous national study, the eight cities were analyzed according to the adequacy of each site's traffic controls. Comparing these ratings with the survey ratings using a statistical ranking procedure, it was found that there was correlation between the two scores in that effective programs produced more adequate work zone traffic controls.

The rank correlation between the survey results and field investigation scores suggested that the quality of the traffic control in work zones is dependent upon the degree of involvement the cities have in regulating construction and maintenance work zones. Because it was shown that, in general, the traffic control programs are inadequate, a model program for a typical city was proposed which if implemented, would help to improve the quality of the traffic controls for work zones.