Quantifying the Environmental Impact of Vehicle Emissions Due to Traffic Diversion Plans for Road Infrastructure Construction Projects: A Case Study in China

Current LCA-based environmental impact assessments rarely consider the environmental impact of traffic network deterioration due to temporary road closures during road infrastructure construction processes. This study proposes a quantification method to evaluate the environmental impact of traffic diversions during the road infrastructure construction process. The environmental impact assessment method ReCiPe 2016 was selected to evaluate the environmental impact of pollutant emissions from deteriorated traffic conditions. Ten types of traffic emissions were estimated by emission factors and traffic conditions. A case study quantified the potential environmental impact of traffic emissions resulting from four diversion plans based on an actual bridge-construction case study in Chongqing city of China. Results revealed that different diversion plans could lead to different final environmental impacts. "Global warming" dominated both "Human health" and "Ecosystems" impacts. In the "Human health" category, more than 95% of the environmental impact was contributed by global warming. Similarly, the impact of "Global warming" was higher than 75% in the "Ecosystems" category. CO2 emissions were the main contributor to the overall "Global warming" impact in all four diversion plans. The traffic speed under traffic diversions before and during road infrastructure construction processes is the major factor influencing the overall environmental impact (endpoint).