Greening Rail Infrastructure for Carbon Benefits

Abstract

Metropolitan Sydney has a network of rail corridors almost 400 kilometers in length, which vary in width from narrow cuttings to wide easements. With an appropriate selection of vegetation species, these corridors can be used to offset carbon emissions from railway operations. Simultaneously, the plantings will improve air quality, reduce pollution and storm water flows, ameliorate urban heating deliver biodiversity gains and improve urban design and property values. A pilot study was carried out on a representative section of one of the major rail lines in Sydney in 2016. A detailed inventory of vegetation on the selected site was obtained through a field survey and a variety of tools were used including i-Tree Eco to benchmark current carbon sequestration and storage (CS&S) levels. Study outcomes include the existing carbon capacity of the rail corridor's above-ground (and substrate) biomass and air pollution reduction. It also presents estimates of CS&S potential by identifying future planting areas within the pilot study corridor. These results are valuable for infrastructure policy formulation directed towards carbon emissions as well as securing the co-benefits noted above.