DENVER — University of Washington researchers and CH2M Hill presented last week the Greenroads sustainability performance metric and best practices for roadway design and construction at the Transportation Research Board (TRB) Annual Meeting in Washington, D.C.

Modeled on existing building rating systems (LEED being the most popular), the Greenroads performance metric is a collection of sustainable roadway design and construction best practices. Each one describes a particular sustainable practice and assigns a point value according to its impact on roadway sustainability.

There are 11 project requirements that must be met in order for a roadway to be considered a Greenroad. These include such items as noise mitigation, low-impact drainage solutions, stormwater management and waste management plans.

There are also 118 voluntary credits that a project team can choose to pursue, such as providing scenic views, using recycled materials, incorporating quiet pavement and accommodating non-motorized transportation. The points associated with the voluntary credits that are achieved are added together to give a final Greenroads score.

"The LEED system has been really successful and has achieved a lot," said primary author Steve Muench, a University of Washington assistant professor of civil and environmental engineering. "Roads are a big chunk of the construction industry that has an opportunity to participate more fully in sustainability practices. I think there’s a lot of opportunity there."

Added Tim Bevan, West Region technology manager for CH2M Hill’s Transportation Business Group: "This helps our industry become more sustainable and shows the public that we can deliver sustainable roadways. In the past, roadway sustainability has not been perceived to be that important, but more and more we’re finding the public is concerned about integrating sustainability principles into roadway design and construction. The Greenroads Manual provides a compendium of research and documentation on best practices for addressing sustainability in roadway projects."

CH2M HILL and the University of Washington came together on this roadway sustainability partnership more than two years ago. Each party brings unique attributes to the Greenroads project.

To learn more about Greenroads or CH2M Hill, please visit, or, respectively.