Work Zone Data Exchange (WZDx)
Version 3.1 of the WZDx Specification was published by the Work Zone Data Working Group this past month. V3.1 enhances and cleans up the specification without making major changes or breaking backwards compatibility. V3.1 of the WZDx Specification and release notes can be found on the WZDx GitHub repository.
The U.S. Department of Transportation (U.S. DOT) will host a webinar on the WZDx Specification on April 29, 2021 as a complementary effort to National Work Zone Awareness Week. Register here.
The Work Zone Data Exchange (WZDx) Specification enables infrastructure owners and operators (IOOs) to make harmonized work zone data available for third party use. The intent is to make travel on public roads safer and more efficient through ubiquitous access to data on work zone activity. Specifically, the project aims to get data on work zones into vehicles to help automated driving systems (ADS) and human drivers navigate more safely.
WZDx Demonstration Grants
The U.S Department of Transportation (U.S. DOT) awarded $2,372,254 on January 15, 2021 for Work Zone Data Exchange (WZDx) Demonstration Grants to fund 13 projects in 13 States. The Notice of Funding opportunity (NOFO) for this WZDx Demonstration closed on August 3, 2020. The purpose of this research program is to increase the safety of the traveling public through the production of consistent public work zone data feeds across jurisdictions. This was a one-time funding opportunity for public roadway operators to make unified work zone data feeds available for use by third parties and collaborate on the WZDx Specification development.
USDOT hosted a solicitation information session webinar on the WZDx Demonstration Grants on June 25, 2020.
Why is the WZDx Specification being developed?
Improving access to work zone data is one of the top needs identified through the USDOT's Data for Automated Vehicle Integration (DAVI) initiative.
Up-to-date information about dynamic conditions occurring on roads – such as construction events – can help ADS and humans navigate safely and efficiently. Many IOOs maintain data on work zone activity. However, a lack of common data standards and convening mechanisms makes it difficult and costly for third parties – including original equipment manufacturers (OEMs) and navigation applications – to access and use these data across various jurisdictions.
Inspired by the General Transit Feed Specification (GTFS), USDOT launched the WZDx Specification to jumpstart the voluntary adoption of a basic work zone data specification through collaboration with data producers and data users. Longer term, the goal is to enable collaborative maintenance and expansion of the specification to meet the emerging needs of ADS.
More broadly, through this project, USDOT aims to identify a repeatable approach to accelerate harmonization of local data sources that can improve roadway safety and efficiency.
A USDOT and American Association of State Highway and Transportation Officials (AASHTO) co-sponsored virtual event on Increasing Worker and Driver Safety through Access to Work Zone Data from May 19, 2020 is available here with associated slides.
Who is involved in developing WZDx?
The Federal Highway Administration (FHWA) and Intelligent Transportation Systems Joint Program Office (ITS JPO) co-led the early stages of the WZDx project and remain actively involved along with the Bureau of Transportation Statistics (BTS), Federal Motor Carrier Safety Administration (FMCSA), and others in the USDOT. Several data producers and data users voluntarily developed version 1.1 of the specification in collaboration with USDOT and have started to set up data feeds based on it.
In 2019, the Work Zone Data Working Group (WZDWG) was established under the Federal Geographic Data Committee (FGDC) Transportation Subcommittee with the primary goal of developing version 2 of the WZDx Specification based on lessons learned from version 1.1 and new insights from the user community. Version 2 of the Work Zone Data Exchange (WZDx) Specification was released in early 2020. Several data producers have already established WZDx feeds based on version 2:
- The Texas Department of Transportation data feed based on WZDx Specification v2.0 can be found here.
- The Massachusetts Department of Transportation data feed based on WZDx Specification v2.0 can be found here.
- The Maricopa County Department of Transportation data feed based on WZDx Specification v2.0 can be found here.
- The Iowa Department of Transportation data feed based on WZDx Specification v1.1 can be found here.
In April 2021, the WZDWG published version 3.1 of the WZDx Specification. Changes made to the WZDx specification for v3.1 sought to enhance the usability of the specification without making major changes or breaking backwards compatibility. The proposed changes were approved in late March of 2021 and were merged into the specification to form WZDx version 3.1.
What changed in version 3.1?
The following new features, refactoring, and fixes were made to the WZDx Specification:
- Add local-access-only restriction
- Add license property to the RoadEventFeedInfo object
- Refactor LaneType enumerated type to deprecate values that can be determined from other properties of the Lane object, such as order, status, and lane_restrictions
- Add road_names property to the RoadEvent object and deprecate road_name and road_number
- Deprecate the total_num_lanes property on the RoadEvent object as the RoadEvent's lanes array can be used to determine the number of lanes
- Add optional bbox property to allow providing a GeoJSON Bounding Box for the WZDxFeed and RoadEventFeature objects
- Add an id property to the RoadEventFeature object in order to provide a road event identifier, ensuring better alignment with the GeoJSON ID recommendations
FHWA is leading efforts, via the Work Zone Data Initiative (WZDI), to develop a standard approach for collecting, organizing, and sharing data on the "when," "where," and "how" of work zone deployment. The goal of this national initiative is to create and accelerate the adoption of a consistent language for communicating work zone activity data across jurisdictional and organizational boundaries. Adoption of this common language will result in enhanced work zone management practices leading to improved mobility and safety in and around work zones for both workers and the traveling public.
First-level support for questions regarding WZDx specifications has been integrated into the USDOT Connected and Automated Vehicle Support Services Help Desk. Our experts can connect you to the answers you need as you work to make travel on public roads safer and more efficient through ubiquitous access to data on work zone activity. For assistance or questions about setting up a WZDx data feed, please contact WZDxSupport@dot.gov.
For information on the WZDx project, WZDI, or anything else related to the DAVI initiative, please contact AVDX@dot.gov.