Center for Weather Impacts on Mobility and Safety (C-WIMS)/Center for Transportation Research and Education (CTRE)

Overview of Weather Related

R&D

Historically

• Partnership with Iowa DOT– Progressive winter maintenance program

• Concept Vehicle• Weatherview• Iowa MDSS evaluation• Early weather impacts safety and mobility

studies• Aurora Program Management

Following the AMS and BASC Reports

• June, 2004 Iowa held a Weather Issues in Transportation meeting (Iowa DOT-FHWA-CTRE)– Over 100 representatives from throughout north

America• Transportation professionals• Technology provider• Enforcement• DOT maintenance field staff• FHWA• Traffic operators• Private carriers

Work Shop Recommendation

• Identified and ranked 25 research project/programs• Called for the creation of a center to provide

leadership for Midwest transportation weather research Issues– Reduction in safety and mobility impacts of weather– Provide leadership in the development of research

agendas– Support a forum for unmet, high priority needs– Raise financial resources– Work with other universities to develop a competitive

research program

Early projects

• Traffic Demand – Traffic Safety – Traffic Flow Relationships

• Travelers will defer and divert trips depending on the type of trip.

Like

lihood

of

Div

ers

ion• Intercity trips

• Intracity discretionary trips• Work trips• Commercial vehicle trips

Traffic Flow Relationships

Capacity = Max FlowFlow = Speed x DensityDensity = 1/Headway

Urban speed and capacity reductions

• Snowfalls & rainfalls of varying intensity

• Reduced visibility

• Head winds

• Cold weather

Safety

Relative Crash Severity

Safety Conclusions

• Drivers learn to driver over the winter weather season

• Winter weather crashes become more severe as:

Urban Rural

Lower Higher

Classification Classification

Current projects

• Isolating crash hot spots

• Winter safety audits

• Measuring impacts of mitigation strategies