Decentralized wastewater management – a Hanoi case study

Introduction Hanoi is currently undergoing a process of intensive industrialization and modernization. The population in the smaller Hanoi urban zone has risen dramatically from 300,000 in 1954 to its current population of more than 1.7 million which is 60% of the total population in the area of greater Hanoi. It is predicted that this will rise to 2.5 million amongst 4.5 million of total population of Hanoi by 2020. This rapid urbanization has created significant environment pressures and unsustainable demands on natural resources. Amongst these are problems related to the provision of infrastructure for collection and treatment of urban wastewater. Out of the total population of greater Hanoi, it is believed that 65% have access to sewerage services and the wastewaster discharged flows into the large drainage channels which flow out from the city. The amount of wastewater in Hanoi is currently estimated to be about 460,000 m3/day. Except for domestic black wastewater (app. 20% of total) which is treated in septic tanks, and a limited amount of industrial and hospital wastewater which passes through preliminary treatment, all wastewaters are discharged untreated into surface water bodies which drain towards the Nhue and Red rivers. The wastewater that flows from the city is widely used by farmers and peri-urban agriculturists living on the edge of the city. The reuse of wastewater increases production in agricultural and aquacultural systems, but there are possible negative impacts on human health of wastewater irrigation activities, which are of concern to the public health sector. The paper focuses on the institutional framework for the provision of services and infrastructure for wastewater management and discusses opportunities for decentralization in the Vietnamese context. The paper uses two examples of wastewater management in two districts of Hanoi to illustrate aspects of decentralization in decision-making processes and management arrangements at the local level. The role of the Peoples’ Committees (PC) in service provision and their linkages and interactions with the agencies responsible for provision of large scale centralized services at the city level are highlighted. The paper also describes how these linkages could be strengthened to improve the quality of service provision, promote greater sustainability, and explores opportunities and constraints to wide replication.