Updated Short-Term Freeway Work Zone Lane Closure Capacity Values

This report reviews previous studies of work zone capacity, summarizes the analysis of new capacity data collected as part of Study 1108, and presents recommendations for estimating the capacity of short-term freeway work zone lane closures. The new data indicate significantly higher average capacities for closures from 3 to 1 lanes and from 2 to 1 lanes than older values reported in the 1985 Highway Capacity Manual. The recommendations for estimating capacity include a base capacity value of 1,600 passenger cars per hour per lane and adjustments for the intensity of work activity, the percentage of heavy vehicles in the traffic stream, and the presence of entrance ramps near the beginning of the lane closure.