Work Zone Performance Monitoring

The CATT Lab developed the Work Zone Performance Monitoring (WZPM) tool for Maryland State Highway Administration to assist in compliance with requirements in the Final Rule on Work Zone Safety and Mobility.

WZPM tool targets three different user groups:

  • Project engineers and managers – Real time performance and alerting capabilities.

  • Public affairs officials – Real-time and historical performance information when responding to customer inquiries.

  • Planners and decision makers – Review of past performance and information on work zone costs associated with user delays.


WZPM tool uses probe vehicle data to show real-time flow information within and around a work zone. The users are able to view the current flow conditions including speed, travel time, and queue length through the work zone or within an arbitrary number of miles upstream and downstream from the work zone. The real-time flow information is plotted and compared to the historical conditions to identify slowdowns, delays, and poor mobility in general. In addition to flow information, WZPM tool calculates User Delay Cost (UDC) associated with each work zone to communicate the cost of time, and fuel consumption and emissions the users are experiencing due to the work zone.


WZPM tool pulls incident information from Maryland State Highway Administration’s Coordinated Highway Action Response Team (CHART) system to show nearby incidents and lane closures that may impact or may be impacted by the work zone. The tool maintains a historical count of nearby incidents to provide additional information related to frequency of incidents and their relationship to the work zone. Live CHART CCTV feeds are also available to allow the tool users to view the traffic conditions.