Strengthen Work Zone Safety and Mobility Through Integrated ITS Strategies and Performance Measurement.

Key lessons learned regarding the WZITS technology strategies included the following. 

Integrate Complementary ITS Strategies for Greater Effectiveness

• Employ queue warning systems in conjunction with variable speed limits to increase effectiveness. Automate systems if possible, but provide adequate operator connectivity if manual intervention is necessary.
• Use precise wording and images to clearly communicate the merging pattern of dynamic lane merge systems to drivers. 
• Install variable speed limit sensors by lane, as by-lane volume and speed data are crucial to adjust speeds in real-time. 
• Review local and state law for permissions, limitations, and applicability of automated speed enforcement systems within a deployment area. 
• Consider installing advance warning signs and offer a probationary period to improve compliance with automated speed enforcement (ASE). This approach helps familiarize travelers with ASE technology. To ensure adequate notice, warning signs should be installed at least 600 feet ahead of the system to inform drivers of its location and operational status.
• Ensure clear visibility and proper spacing when deploying work zone notification systems. Agencies should place equipment to avoid obstructing drivers’ views of workers and maintain adequate distance between warning devices and construction areas to enable safe and smooth driver reactions.
• Provide adequate acceleration and deceleration distances for construction vehicles when configuring entering/exiting notification systems. 
• Conduct feasibility studies and benefit and cost analyses on proposed temporary ramp metering locations to validate applicability in solving targeted problems (mainline congestion, safety issues at merge zones, construction impacts, special event impacts, etc.). 
• For real-time traveler information systems, deploy detection units with remote monitoring and configuration. This can allow for battery-power savings as well as early detection of malfunctioning units and other inconsistencies. For incident management systems, collect data on speeds, crashes, incident clearance, etc. to evaluate the system for accuracy and reliability. This is critical to gain and maintain public trust and compliance.

Build Work Zone Performance Measurement on Consistent Baseline Data

• Establish a foundation of consistent baseline data collection (before, during, and after construction) to evaluate short- and long-term impacts.
• Collect standardized data on traffic volumes, speeds, queues, crashes, and exposure using traditional sensors, automated systems, probe data, or application programming interface (APIs) that aggregate multiple sources.
• Use a tiered performance framework aligned with agency goals, project duration, anticipated closures, and available resources.