Roughness Optimization of Road Networks: An Option for Carbon Emission Reduction by 2030

The Paris climate agreement requires all nations to reduce greenhouse gas (GHG) emissions. Accordingly, countries have made ambitious targets to be achieved by 2030. Road transport as a major GHG contributor has been embraced by electric vehicle and renewable energy (EV&RE) initiatives to reduce emissions. However, the projected EV&RE penetration by 2030 is small in contributing to the emission reduction targets. On the other hand, life cycle carbon footprint assessment of road infrastructure identifies that rolling resistance due to road roughness contributes most of the GHG emissions. Reduction of networkwide roughness level is often difficult to achieve because of an ever-constrained funding regime. This study found that roughness level can be optimised with both carbon emission reduction and positive benefit-cost outcomes. This result may, therefore, help in achieving important road sector contributions toward 2030 emission reduction targets.