Urban semicentralised supply and disposal: innovations and challenges for Hanoi, Vietnam

The development of the world population is characterised by two trends: absolute population growth and rapid urbanisation. In the urban region of Hanoi, the capital of the Socialist Republic of Vietnam, extensive urbanisation contributes to a deficient provision of infrastructure causing environmental degradation and health problems for large parts of the population. The protection of the environment, as well as the preservation of historic urban fabric, requires new approaches to infrastructure supply. The semicentralised approach, focusing on supply and treatment structures on the neighbourhood level, offers a solution to the challenges imposed by urbanisation. Contrasting existing plans for conventional centralised sewerage systems in Hanoi, it allows the closing of certain cycles on a local level. Within an integrated approach local technologies, such as septic tanks, can be used further on. As it is process oriented, existing management structures of waste and wastewater treatment are to be considered and incorporated.