The Work Zone Data Exchange (WZDx) data specification is part of a larger effort by the Federal Highway Administration (FHWA) to modernize work zone data. Prior to the Work Zone Data Initiative (WZDI) and the WZDx specification, there was no standard for handling the complexities of work zone data lifecycle management, work zone common core data elements, and their definitions. The specification itself was developed to provide a reference guide or standard method of digitally communicating work zone activities. Early versions of the specification focused on communicating work zone data elements to connected and autonomous vehicles. More broadly, work zones are dynamic and involve many stakeholders, and developing a standard definition for communicating work zone information digitally is essential to the increasing demands of agencies to become more data driven with their operations and maintenance activities.
WZDx Version 1.x was developed to provide infrastructure owners and operators (IOO) the ability to transmit authoritative data to mapping and equipment manufacturers of connected and autonomous vehicles (CAV) with the goal of adding additional use cases in the future. In 2019, the Work Zone Data Working Group (WZDWG) was established to advance the WZDx specification. Several changes were identified and made to the specification before the release of version 2, such as adopting a relational model approach, eliminating nested tables, and making the specification more scalable. The GeoJSON format was also formally adopted by the group to facilitate easier use of the data by consumers. Road closure impact reporting was simplified to include partially closed, fully closed, and fully open options. Lane-level restrictions were added to the specification so that agencies could report work zone impacts for each lane of roadway, when available.
Subsequent versions of the specification include additional agency functions and additional external stakeholders.
Only a few agencies have successfully implemented the work zone data specification into production. This low adoption rate exists despite a high degree of interest in the specification itself based on comments found on the official GitHub site and discussions between IOOs and the FHWA. Based on these comments and conversations, the slow adoption of the standard appears to stem from other roadblocks and challenges. Following is a list of challenges that agencies face in working with work zone data:
Efforts to advance and develop the specification can be found on the WZDx GitHub website, which is open and available to the public. The site also contains tools for validating JSON files and developing a data feed. These tools are currently only available for version 1.1, but version 2.0 tools are expected in the near future. In January 2021, the USDOT awarded nearly $2.4 million in WZDx demonstration grants across 13 states to aid adoption.
08-119 Research Products:
Roadway work zones can create hazardous conditions for motorists, pedestrians, and highway workers, and better, more accurate, and more timely data can reduce the risks of driving in work zones. Collecting, consolidating, and distributing this information, however, has been an ongoing challenge. The objective of Federal Highway Administration’s (FHWA) Work Zone Data Exchange (WXDx) initiative was to develop and promote the use of a common specification to collect and share data on work zone activities. This report presents case studies from five agencies on their past, on-going, and planned use of smart work zone technologies as a source of data for their WZDx feeds. The intended audience for this report includes state, regional, and local agencies seeking to use smart work zone technologies, as well as those looking to establish a WZDx feed and those integrating real-time data with other data sources, such as work zone planning and tracking systems. This report will assist agencies by highlighting recent and ongoing efforts by peer agencies; summarizing their challenges, lessons learned, and recommendations; and providing additional resources.
Additional Resources:
FWHA developed this framework to assist transportation agencies and the work zone stakeholder community in establishing a standardized approach for digitally describing work zones and for communicating WZED with contractors, neighbor agencies, third-party data consumers, and other key stakeholders.
Iowa Department of Transportation (IDOT) implemented its WZDx data feed through a data integration project that extracts and transforms data from existing systems and then republishes that data using the WZDx specification.
Maricopa County Department of Transportation (MCDOT) is a regional agency responsible for maintaining roadways within the Phoenix metropolitan area in cooperation with the Arizona Department of Transportation (ADOT). Both agencies share responsibility for maintaining a regionally integrated traffic data-sharing entity, called AZTech, which serves as the central data-sharing system across the region’s traffic and emergency management agencies.
The purpose of the WZDI is to develop a recommended practice for managing work zone event data (WZED) and to create a consistent language, through the development of a data dictionary and supporting implementation documents, for communicating information on work zone activity across jurisdictional and organizational boundaries.
