The urbanisation-environment conflict: Insights from material stock and productivity of transport infrastructure in Hanoi, Vietnam.

Developing regions experience rapid population growth and urbanisation, which require large quantities of materials for civil infrastructure. The production of construction materials, especially for urban transport systems, however, contributes to local and global environmental change. Political agendas may overlook the environmental implications of urban expansion, as economic growth tends to be prioritised. While elevating the standard of living is imperative, decision-making without careful environmental assessments can undermine the overall welfare of society. In this study, we evaluate the material demand and in-use stock productivity for the large-scale development plan for transport infrastructure in the city of Hanoi, Vietnam, from 2010 to 2030, combining geospatial and socioeconomic data with statistics on roads and railways. The results show that the total material stock could rise threefold from 66 Tg in 2010 to 269 Tg in 2030, which roughly translates to an addition of 30 Empire State Buildings per year by mass. The materials we account are required for construction exceed the availability of local sand and will need to be gathered farther away. Furthermore, the material stock productivity of the transport infrastructure appears to have been declining overall since 2010, and this trend may continue to 2030. These findings demonstrate the importance of informing urban planning with a comprehensive assessment of construction materials demand, supply capacity, and environmental impacts. Policy priorities for improving the in-use stock productivity are also recommended towards achieving a more efficient utilisation of natural resources.