Safety and Mobility Impacts of Winter Weather – Phase 3

Project Details
STATUS

Completed

START DATE

07/01/12

END DATE

09/30/14

RESEARCH CENTERS InTrans, CTRE, CWIMS
SPONSORS

Federal Highway Administration State Planning and Research Funding
Iowa Department of Transportation
Mid-America Transportation Center
U.S. DOT RITA

Researchers
Principal Investigator
Zachary Hans

Director, CWIMS

Principal Investigator
Neal Hawkins

Associate Director, InTrans

About the research

Highway agencies spend millions of dollars to ensure safe and efficient winter travel. However, the effectiveness of winter-weather maintenance practices on safety and mobility are somewhat difficult to quantify. Safety and Mobility Impacts of Winter Weather – Phase 1 investigated opportunities for improving traffic safety on state-maintained roads in Iowa during winter-weather conditions. In Phase 2, three Iowa Department of Transportation (DOT) high-priority sites were evaluated and realistic maintenance and operations mitigation strategies were also identified.

In this project, site prioritization techniques for identifying roadway segments with the potential for safety improvements related to winter-weather crashes, were developed through traditional naïve statistical methods by using raw crash data for seven winter seasons and previously developed metrics. Additionally, crash frequency models were developed using integrated crash data for four winter seasons, with the objective of identifying factors that affect crash frequency during winter seasons and screening roadway segments using the empirical Bayes technique.

Based on these prioritization techniques, 11 sites were identified and analyzed in conjunction with input from Iowa DOT district maintenance managers and snowplow operators and the Iowa DOT Road Weather Information System (RWIS) coordinator.

TOP