Iowa DOT Intelligent Work Zone Program Support

Statewide, Iowa

The Iowa DOT Traffic Critical Project (TCP) Program is intended to address mobility and safety impacts caused by work zone activities with the goal of providing safe and reliable transportation systems in Iowa. SRF has provided on-going guidance and support for the development, deployment, evaluation, and continued technical support for this program by:

  • Coordinating and supporting Intelligent Work Zone (IWZ) applications by establishing processes and procedures for the IWZ team in the areas of design, deployment, maintenance, and operation.
  • Developing processes and procedures that allow district and design representatives to determine which projects are TCP and aid in selection of appropriate mitigation measures.
  • Assisting in establishing policies to support the institutionalization of the TCP Program into the DOT’s culture.

As one of the first tasks in providing IWZ systems SRF prepared an RFP that used a qualification-based procurement process to select a contractor to provide statewide IWZ deployment services. A stand-alone procurement was used – the IWZ work is not incorporated into the contract for the general contractors of each construction project. We reviewed a variety of IWZ applications for their relevance in addressing safety and mobility impacts. SRF then led the effort to coordinate the IWZ team through design, deployment, evaluation, maintenance, and operation of the systems. SRF worked closely with the IWZ vendor, developing preliminary IWZ concepts, performing device staking, assisting with software integration into the Automated Traffic Management System (ATMS) software, and developing the alert processing logic required for end-of-queue warning. This work included determination of the backhaul communication method. We then performed system monitoring to ensure all equipment was functioning and communicating properly with the traffic management software. The team performed daily and end of season system evaluation and review using performance data and lessons learned each year to develop efficiencies for future deployments and goals.

SRF also developed guidance documents in cooperation with DOT staff with the goal of providing a useful process for the selection of TCP projects and mitigation efforts at the district level. We are also working with Iowa State University to evaluate the ability of all mobility and safety mitigations to achieve the TCP Program goals. This analysis will enable the DOT to determine the effectiveness of various mitigations as well as monitor the performance of the program’s ability to select the appropriate projects, and identify mobility and safety needs in the work zone.