Speed Control Through Freeway Work Zones: Techniques Evaluation

In this paper, the implementation and evaluation of four techniques for improving the effectiveness of speed zoning in construction areas on multilane freeways are presented. The techniques are (a) the flagging procedure of the “Manual on Uniform Traffic Control Devices” (MUTCD), ( b) the use of the MUTCD flagging procedure plus having the flagger point at a nearby speed limit sign with the free hand after motioning motorists to slow, (c) a marked police car with cruiser lights and radar active, and (d) a uniformed police officer to control traffic. Each of the techniques was applied continuously on a six-lane freeway for a period of 10 to 15 days. The results of the analysis indicate that all four techniques can provide significant reduction in traffic speed through highway construction zones. The flagging methods were effective in construction areas where one lane remained open to traffic. The law enforcement methods demonstrated a stronger speed reduction capability, particularly when the lane closures result in two or more lanes open. The construction projects used for the collection of field data required speed reduction from the regulatory 55 mph to an advisory 45 mph. Although the law enforcement techniques were determined to be effective, their implementation requires a high degree of administrative coordination and cooperation involving police departments, highway officials, and construction contractors.