CTRE is an Iowa State University center, administered by the Institute for Transportation.

Address: 2711 S. Loop Drive, Suite 4700, Ames, IA 50010-8664

Phone: 515-294-8103
FAX: 515-294-0467

Website: www.ctre.iastate.edu/

Iowa State University--Becoming the Best

Wet Reflective Pavement Marking Demonstration Project

Water decreases pavement marking retroreflectivity significantly


Principal investigators:

Co-principal investigators:

Student researcher:

Project status


Start date: 08/01/08
End date: 07/31/11


Report: Wet Reflective Pavement Marking Demonstration Project (4.39 mb pdf) January 2012

Tech transfer summary: Wet Reflective Pavement Marking Demonstration Project (1.37 mb pdf) Nov 2011



About the research


One of the leading complaints from drivers is the inability to see pavement markings under wet night conditions. This issue is a major source of dissatisfaction in state department of transportation (DOT) customer satisfaction surveys.

Driving under wet night conditions is stressful and fatiguing for all drivers, but particularly so for the more vulnerable young and older driver age groups.

This project focused on the development of a two-year long-line test deck to allow for the evaluation and demonstration of a variety of wet-reflective pavement marking materials and treatments under wet night conditions.

Having the opportunity to document the performance of these various products and treatments will assist the Iowa DOT and local agencies in determining when and where the use of these products might be most effective.

Performance parameters included durability, presence, retroreflectivity, and wet night visibility. The test sections were located within Story County so that Iowa DOT management and staff, as well as local agencies, could drive these areas and provide input on each product or treatment.