Business model assessment in faecal sludge management in selected Vietnamese cities

An assessment of business models in faecal sludge management (FSM) in 3 largest Vietnamese cities of Hanoi, Hai Phong, and Ho Chi Minh has been conducted through interview of 1,000 households and survey at 20 FS emptying operators. The public enterprises keep a significant market share for FSM. However, these enterprises run FSM business as a ‘‘must do” activity, which is subsidized by the city’s budget. In order to reduce operation costs and to make benefit, most of private enterprises are practicing illegal FS dumping. Financial status of private enterprises looks less optimistic in scenarios where FS is required to be brought to landfill or composting plant. A number of enterprises would not find capital recovery within 5 years, and some others would face loss. For sustainable FSM business, costs for adequate FSM should be recovered, while regulatory support and coordination role of local authorities are needed

The economic returns of sanitation interventions in Vietnam

Results of sanitation interventions in 9 rural and 8 urban sites have been evaluated, comparing open defecation with different range of sanitation facilities. Both quantitative and tangible benefits of sanitation and hygiene improvements versus averted costs of interventions were analyzed. Study results show improved sanitation is a socially profitable investment – pit latrines in rural areas have an economic return of at least 6 times the cost, and off-site treatment options in urban areas have an economic return of at least 3 times the cost. Net benefits from low-cost options are especially high, offering an affordable opportunity to poor households. Sanitation options that protect the environment are more costly to provide, but while environmental benefits are difficult to quantify in economic terms, the benefits are highly valued by households, tourists and businesses. Study results provide valuable information to allocate adequate resources for sanitation and hygiene improvement at central and local levels

Co-treatment of organic fractions of urban waste for energy recovery: a case study from Hanoi city, Vietnam

The authors have quantified material and energy flows in two options of co-treatment of organic fractions of wastes by composting, and by anaerobic digestion. The results shown thermophilic anaerobic co-digestion of septic tank sludge, sewage sludge and organic municipal solid waste has provided the biogas yield of 19.6 m3 per ton of mixed waste, equal to 114 kWh of heat and power. The calculation for the case of Long Bien district, Hanoi city has shown anaerobic co-digestion of waste fractions could generate 111,220 kWh of heat and power per day, helping the waste treatment complex to be selfsufficient in terms of energy. Besides, 32.2 MWh/day of surplus energy could be sold to the grid. This option also reduced emission of greenhouse gases versus composting. The study can be used as basis for cost-benefit analyses in selection of appropriate urban waste management options aiming at efficient utilization of engineering infrastructure systems, waste treatment and resource recovery

How cheap can hygienic latrines be?

A construction and operation costing of 12 types of hygienic latrines widely used in rural areas of Vietnam and presented in the Hygienic latrine Manual of the Ministry of Health, using traditional construction materials has been conducted. The cost of latrines using traditional construction materials is ranging from USD37.5 (VIP) to USD194.4 (Septic tank constructed by brick for treatment of black and grey wastewater from sitting bowl toilet). Annually averted O&M costs of Vietnamese latrines range from USD1.86 (VIP) to USD 4.58 (wet latrine with septic tank) per capita per year. Costs of hygienic latrines can be further reduced, applying solutions such as using local materials for construction, reducing the tank volume by using the water-saving flushing devices or applying more frequent tank emptying services and mass production of latrine components. The less a hygienic latrine costs, the more chance for poor people in different places can get access to improved sanitation

Novel application of local GAC adsorption to remove organic matters and pesticides in rural drinking water treatment

Novel application of granular activated carbon (GAC) using renewable and low cost materials to remove pesticides and organic matters was studied in the rural water treatment plant (WTP), in Hai Duong province, Vietnam. The treatment efficiencies of the a series of processes such as coagulation/ flocculation, horizontal sedimentation, rapid sand filtration and adsorption using three types of GAC (activated carbon from bituminous coal, from bamboo and from coconut shell) and the overall treatment trains were evaluated by studying several parameters such as turbidity, COD, pesticides (chlorpyrifos, diazinon, carbofuran). Results show that the two locally produced adsorbents have a similar efficiency to commercial activated carbon for adsorption. The removal efficiency was somewhat lower for both materials, but in the same order of magnitude. The removal of pesticides and organic matter with a column filled with activated carbon derived from bamboo was found the best among the two locally produced materials, approximately 30% and 23% higher than those observed for the column filled with activated carbon from coconut shells. It concludes that bamboo-derived activated carbon adsorption can be employed on an alternative to commercial activated carbon and could be a feasible option for drinking water treatment

Technologies for sanitation: how to determine appropriate sludge treatment strategies in Vietnam

Developing appropriate technologies for the sanitation chain in low- and middle-income countries is crucial to protect public and environmental health. This includes treatment systems for the sludge produced in onsite and centralized systems (i.e., faecal and wastewater sludge). As the quantities and characteristics of sludge differ from city to city, this requires context-specific technologies. This case study was conducted to identify potential management strategies in five cities in Vietnam. The influence of the enabling environment, existing infrastructures, local sanitation practices and socioeconomic contexts on the selection of technology was assessed through literature reviews, household surveys and interviews. A checklist of influential aspects is presented to make best use of local opportunities and minimize the risks of technology failure. This approach is applicable to develop sludge management strategies in other cities

FAQ: faecal sludge quantification and characterization - field trial of methodology in Hanoi, Vietnam

Characterizing and quantifying faecal sludge (FS) at a city-wide scale in low- and middle-income countries is essential for designing and planning appropriate FS treatment facilities. However, there currently is no accurate methodology for the estimation of these values. The FAQ (faecal sludge quantification and characterization) study developed a methodology, and is validating it in Hanoi, Vietnam and Kampala, Uganda. The method utilizes spatially analysed demographic data as a predictor of FS characteristics. Extensive sampling has been conducted to field test the presented method. This paper presents results of collected and analysed secondary data, and preliminary results of the TS, VS, COD and SCOD concentrations from household septic tanks in Hanoi, which were on average 26,471, 19,395, 37,541 and 713 mg/L respectively, and ongoing data analysis is being conducted

Decentralized wastewater management - a Hanoi case study

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