The University of Washington and CH2M HILL have released a project-based roadway sustainability rating system that provides performance metrics and best practices for roadway design and construction. It covers the design process, construction activities within the work zone, materials hauling activities, production of Portland cement concrete and hot mix asphalt.
The rating system was unveiled at the Transportation Research Board (TRB) Annual Meeting in Washington, D.C.
The “Greenroads Rating System v1.0 (short version PDF)” is segmented into two major sections: Project Requirements and Voluntary Credits. The rating program features 11 “Project Requirements” that must be met in order to be certified Greenroads. Requirements include noise mitigation, low-impact drainage solutions, storm water management and waste management plans.
Participants in the program can also choose to pursue any of the 118 “Voluntary Credits” such as providing scenic views, using recycled materials, incorporating quiet pavement and accommodating non-motorized transportation. The points associated with the Voluntary Credits are tallied together for a final Greenroads score. Click here for the 400-page manual.
Sustainability benefits include the reduction of raw materials use, water use, air emissions, wastewater emission, soil/solid emissions; optimized habitat and land use, and improved human health and safety, according to the report.
In the future, roadway design and construction projects may be able to pursue several levels of certification based on the Voluntary Credit points. There are four certification levels proposed: certified, silver, gold, and evergreen.
— Certified: All project requirements + 32-42 Voluntary Credit points (30-40 percent of total)
— Silver: All project requirements + 43-53 Voluntary Credit points (40-50 percent of total)
–Gold: All project requirements + 54-63 Voluntary Credit points (50-60 percent of total)
— Evergreen: All project requirements + 64+ Voluntary Credit points (>60 percent of total)
Currently, the University of Washington and CH2M HILL offer the evaluation tool for voluntary application.