Operational stage evaluation of urban roads in achieving carbon neutrality

Current methods for assessing road sustainability require a comprehensive approach considering traffic-related pollution and analyzing the environment’s capacity to mitigate it. This study aims to develop a methodology for evaluating the sustainability of the operational stage of the road by introducing a novel metric called “Level Of Green (LOG).” The LOG concept establishes a relationship between the quality of the roadway environment and the emissions produced by road traffic. A comprehensive approach was adopted by integrating pollution load and carbon sink capacity for specific roadway segments in India. The pollution load was quantified using emission factors, while the carbon sink capacity was assessed using the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model. The annual traffic load was used to estimate the pollution load for a given year. The Land Use and Land Cover (LULC) map was generated using ArcGIS, and carbon pool data was used as input into the InVEST model to determine the carbon sink capacity. The Level of Green (LOG) was calculated by determining the ratio of emissions to carbon sink capacity, providing a quantitative measure of the sustainability of the road. In this study, the LOG was evaluated for ten locations, and the results indicated that all of them fall under sub-critical conditions, with LOG values below 1. This suggests that these locations are currently sustainable, as traffic emissions do not exceed the environment’s capacity to absorb pollution.Additionally, a web-based platform named ‘Sustainable Adaptation of Mobility Action (SAMA)’ was developed to quickly evaluate the LOG of any road segment. SAMA provides the capability to assess the sustainability of any road segment, considering factors like emissions and carbon sink capacity, and thereby helps to evaluate the LOG of any road segment quickly. Future research could enhance the LOG metric by including additional pollutants, longer road sections, and factors like seasonal variations, social and economic influences, and environmental conditions for a more comprehensive assessment of road sustainability.