Evaluation of Rural Intersection Treatments

Project status

In progress

Start date: 07/01/15
End date: 11/30/17


Principal investigators:

Co-principal investigators:

About the research

In Iowa, intersection crashes account for 30 percent of severe crashes, with 40 percent of those crashes occurring in rural areas. Rural intersection crashes can be very severe due to the high approach speeds present. Additionally emergency response is often longer in rural areas which exacerbates the severity of crashes when they do occur. Crashes at rural intersections are frequently a result of failure to yield. As a result, agencies attempt to find countermeasures which encourage drivers to stop and yield appropriately. As noted in the background section below, a number of countermeasures have been utilized to reduce crashes and improve intersection safety. In several cases the treatment has showed mixed results and in other cases, only limited information about the effectiveness is available. Since even low cost treatments require some maintenance, it is important for agencies to have better information about the effectiveness of the various treatments before investments are made. The objective of this research is to select one or two promising rural intersection treatments and evaluate their impact on improving safety. The team will select high crash intersections and then evaluate the treatment. Since it is difficult to conduct a crash analysis in the short-term, measures of effectiveness will focus on unsafe driver behaviors and evaluate how the treatments affect those behaviors. The study will focus on rural two-way stop controlled intersections. The intent is to evaluate lower-cost devices (less than $5,000). Changes in geometric conditions (i.e., construction of a roundabout, addition of turn lanes) is beyond the scope of this study.



  • Iowa Department of Transportation
  • Iowa Highway Research Board
  • Midwest Transportation Center