Measuring work zone performance
In California, they typically measure travel time (and hence, delay) through the work zone when the project conditions/traffic conditions warrant and problems are anticipated. This is done only occasionally for major projects using traffic teams. They limit delay to a maximum of 30 minutes above the typical travel time but usually strive for a maximum of 0-15 minutes of delay, except under special conditions. California DOT is also strongly urging the consideration of innovative project scheduling during the planning process (such as full closures and extended continuous closures) to shorten the overall project duration and reduce inconvenience to the public.
California has used advanced warning information systems as pilot projects in a few locations on an experimental basis (traffic sensors sending information to a main terminal that disseminates messages to changeable message signs). They do not typically measure queue, but field crews watch for backups and notify the Resident Engineer and District Traffic Managers when queues develop. The decision is then made as to whether or not to make adjustments or to pick up the lane closure.