A sustainable roadway

A sustainable roadwayBy Melissa Nipper

Greenroads, a rating system for roadway design and construction, is paving the way for agencies, organizations, contractors and others who desire a tool to implement and assess sustainability strategies.

Developed by the University of Washington and CH2M HILL, a global full-service consulting, design, construction and operations firm, Greenroads is a performance metric for roadway design and construction that awards points for more sustainable practices.

It’s becoming a useful tool for agencies across the country, including the Oregon Department of Transportation (ODOT), a Greenroads research sponsor that is currently testing the rating system with several of its projects.

“The overall goal of Greenroads is to improve roadway sustainability,” said Steve Muench, associate professor in the civil and environmental engineering department at the University of Washington. “It’s a set of best practices that works within existing regulations. If there is a choice to be made within existing regulations, Greenroads encourages you to choose the sustainable option.”

Mapping sustainability

Greenroads was modeled after Leadership in Energy and Environmental Design (LEED), the internationally recognized green building certification system developed by the U.S. Green Building Council. Muench hopes Greenroads will provide a similar benchmark for roadways by spotlighting sustainable practices for roadway construction.

“You can look at what’s happened in the building industry over the last 15 years and use it as a looking glass for roadways,” Muench said. “It’s likely things will move the same way with a greater awareness of sustainability.”

Awareness will also increase as more projects use the Greenroads rating system and eventually become certified. Certified projects will receive permission to use the Greenroads’ logo on road signs, marketing materials and other publicity, Muench said.

Owner agencies, developers, design consultants and contractors could choose to pursue official certification or use Greenroads in other ways that are either voluntary or prescriptive. For instance, developers and designers could use Greenroads as a list of potential ideas for improving the sustainability of a roadway project.

Project teams could also use Greenroads point values or certification levels as goals or benchmarks for new roadway projects or metrics by which they can measure and manage their roadway sustainability efforts. The road to certification

How does a road become Greenroads certified?

To help quantify the sustainable attributes of a roadway, the developers of Greenroads established best practices that are divided into two types — required and voluntary.

“What we have done with Greenroads is suggest specific performance metrics so that if your concern is sustainability, here are some metrics to look at,” said Sam Seskin, transportation planning director with CH2M HILL.

Required best practices, called Project Requirements, are those that must be done as a minimum in order for a roadway to be considered a Greenroad.

Voluntary best practices, or Voluntary Credits, are those that may optionally be included in a roadway project. Each Voluntary Credit is assigned a point value depending upon its impact on sustainability.

“We have developed documentation and information that supports each credit and describes what the user can do to comply,” said Tim Bevan, senior project manager at CH2M HILL.

Asphalt is a major factor in several Voluntary Credit categories, including those dedicated to pavement technologies, materials and resources, and construction activities.

“When you consider asphalt as a material, the contractors who place it and the producers who make it, the asphalt industry is extremely relevant to one-half to two-thirds out of the total 108 voluntary credits,” Muench said.

Greenroads also allows a project or organization to create and use up to 10 points worth of its own Voluntary Credits (called custom credits), subject to approval.

Project teams apply for points by submitting specific documentation supporting the Project Requirement or Voluntary Credit they are pursuing. Once a project is complete, the Greenroads independent review team verifies the application and assigns a Greenroads score.

Greenroads projects may also choose to pursue a certification level — Certified, Silver, Gold and Evergreen — based on the points associated with the Voluntary Credit achieved. The more points earned, the higher the certification level.

While no projects have received official Greenroads certification yet, Greenroads has reviewed 20 pilot projects and studied another 30 submitted projects. The Greenroads Foundation, a non-profit, third-party corporation was established in the summer of 2010 to manage certification reviews for roadway and bridge projects using the Greenroads Rating System. Muench anticipates the first official Greenroads certification will take place in 2011.

Testing the tool

ODOT currently has four projects that are Greenroads test subjects, said Lyn Cornell, ODOT research coordinator and Greenroads project manager. “We are evaluating Greenroads to see if ODOT wants to adopt it in the future,” Cornell said. “Greenroads is a wonderful source. One of the best things about it is nothing is forced and you can just use it as a tool.” A recent ODOT project using Greenroads in an advisory capacity is the U.S. 97 Lava Butte to South Century Drive project, located in central Oregon along U.S. 97.

This project involved increasing the capacity of the existing two- and three-lane highway to four lanes, reconstructing an interchange and constructing an alternative access to Lava Lands Visitor Center.

“We did not use the Greenroads criteria when developing the project,” said Stephanie Serpico, project manager with ODOT. “Once the project was in construction, we went back and reevaluated based on the criteria.”

The project rated above average based on Greenroads’ criteria, Serpico said.

It earned points for many sustainable practices, including credit for using reclaimed asphalt pavement (RAP). According to the Lava Butte Greenroads’ case study, ODOT personnel estimated that using RAP on the project saved $10 to $15 per ton of pavement.

The project also earned points for obtaining at least 90 percent (based on cost) of materials, including asphalt, from suppliers located within a 50-mile radius of the project site. Using local suppliers for the asphalt reduced the costs for transportation.

“I think Greenroads is a very helpful tool in defining what is a sustainable project,” Serpico said. “We are often asked how are ODOT projects sustainable, and Greenroads provides a quantitative method of answering that question.”

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