Field Evaluation of Flashing Arrowboards at Freeway Work Zones

This report documents research conducted in the evaluation of flashing arrowboards when located in advance of lane closure work zones. The effects of supplemental arrowboard placement were compared to the effectiveness of the arrowboard placement normally used by District 14 of the SDHPT. The research indicates that a supplemental arrowboard placed in advance of the beginning of a cone taper can be extremely effective if the sight distance to the arrowboard improves the effective sight distance to the work zone. This improvement is dependent on the horizontal and vertical alinement of each work zone. The supplemental arrowboard can be placed up to 2500 ft. in advance of the taper to increase the effective sight distance to the work zone. Distances greater than 2500 ft. may result in drivers moving back into the blocked lane.