Eco-Street: Quantifying Energy Efficiency of Roads over Their Lifespan

The objective of this paper was to investigate the practicality and benefits of applying theoretically proposed environmental competency measures to the construction of roads, with LEED standards for building construction as the initial framework for analysis. A short coming of credit based systems for environmental evaluation is that they have the potential to reward activities of minimal positive environmental impact activities equally with activities that have a greater impact on the environment. A rating system that certifies projects on achieving a certain level of energy conservation in measureable units of consumed energy (Eco-Streets) is developed herein. To validate the rating system developed, three road design options of varied environmental impact are evaluated with the Eco-Streets rating system. For comparative purposes, the road cases are also evaluated under Green Roads; a credit-based system developed by the University of Washington for environmental rating of roadways. The results of Eco-Street and Green Roads agree other with respect to overall environmental benefit. The conventional road structure was the least desirable option environmentally, followed by remove and replace using recycled materials, with the best results for in-place recycling and full depth reclamation design option. However, there was a significant difference in total energy consumption calculated for the design options under Eco-Street with respect to the transportation of materials, there is a significant difference. Under Green Roads all options are rated equally. Since transportation of materials consumes a large portion of the energy consumed during construction, it is believed that points attributed to transportation of materials under Green Roads are insufficient.