Modification of Existing EcoSan Toilets in Rural Bangladesh

Abstract

Sanitation, one of the most vital parts in environment is a great concern for the developing countries in the world. Bangladesh is one of the most threatened countries of climate change due to its vulnerable geographical location which led to severe water and sanitation crisis. Common features of defecation facilities in the country include pit toilets with or without water seal, hanging toilets, direct pit pour-flash toilets, toilets with septic tank, urine diversion toilets etc. The health burden associated with poor sanitation condition is staggering and hence there is a dire need of holistic approach to call for hygienic, eco-friendly and sustainable sanitation technology. EcoSan toilets are found as one of the most appropriate and proven technological options, as these are cost effective, environment friendly as well as socially sound. Eco-San toilet is a urine diversion toilet and based on the idea that urine, feces and water are resources in an ecological loop. The toilet has a special squat plate in which urine is diverted through the pipe and thus separated from the feces which fall directly downwards into a vault. Wooden ash is added to cover the feces after every visit and thus feces is dried out for which easier handling and transferring is possible. The urine can be collected separately, making it available as a liquid fertilizer. Also the solid component, being semi dry, it does not smell so much and its potential as a fly breeding medium is much reduced compared to the mixes of urine and feces. Eventually, the feces become completely composted. Moreover, it does not need to use water for cleaning and flashing. However, Eco-san has a great potential to contribute safely in transforming human urines and faces into organic fertilizers for eco-friendly agriculture and producing food-crops. This study had been carried out in Banshbaria village in Kcshabpur Upazila of Jessore District due to its high vulnerability to water logging. From geographical perspective, the village was located in the catchments of river "Kobadak". This village was named EcoSan village because 94 no. of EcoSan toilets had been installed in this village by foreign agencies from 2008 to 2012. Due to siltation, the river spread over adjacent area of the village is gradually losing its flow capacity. As a result, the waterlogged condition in the monsoon had damaged the management and safe disposal of human excreta in this area. Pit latrines with various types of super-structure as well as open spaces used for defecation are usually flooded in the rainy season which cause pollution to water sources in the area. The villagers had been suffering from water borne diseases like diarrhea, dysentery, skin diseases with fever, etc. It was found that they were extremely demanded of improved sanitation options (toilets) for safe disposal of human excreta in waterlogged condition. Specific objectives of the study were to (1) study the field performance of existing EcoSan toilets regarding its socio-economic acceptance by rural population in Bangladesh; (2) identify the technical problems in the operation and maintenance of EcoSan toilets; (3) investigate any possible contamination of groundwater/surface water resources around the EcoSan toilets; and (4) Design modification of EcoSan toilets for its sustainable development in rural Bangladesh. A detailed field survey was carried out in the study area to investigate the level of socio-economic acceptance of EcoSan toilet by rural population. Social acceptance of the EcoSan toilet was found to be 31.25% on the basis of various operation and maintenance aspects in real field situation such as waterlogged condition, religious aspect, recycling of human urine and feces into organic fertilizers for agriculture, children and elderly people users, etc. On the other hand, considering the chemical properties of nutrients in urine and feces derived fertilizer, equivalent profit of recycled human excreta was found to be BDT 286.28/EcoSan user/year. EcoSan toilets were treated as a source of business through community based organization (CBO). This study revealed that the medical cost and income loss after installation of the EcoSan toilet was far less than it was before. The EcoSan toilet users were also found to be well-practiced in hygiene behaviors. Several technical problems in operation and maintenance of the existing EcoSan toilets were identified in this study. The major operational difficulties include: removing lid of defecation hole before defecation; being transferred from defecation place to anal washing place; adding ash into feces chamber and placing the lid over the hole. Moreover, the identified maintenance problems include: cleaning the evaporation bed, replacing the corroded heat panel, removing the blockage in pipes, extracting the feces from vault, etc. Various surface/ground water samples were collected around EcoSan toilets and water quality parameters were analyzed to investigate any contamination of surrounding water sources. Water quality parameters were selected in two categories: a) physicochemical such as pH, S042 , P043 , NO3 , DO, BOD5, COD and b) microbiological such as total coliform, fecal coliform, and E.coli. Experimental results of pH, SO42, PO43 , NO3 in both surface/ground water were found to be satisfactory within the acceptable limit of Bangladesh standards. BOD5 value was higher in surface water than groundwater but COD value was lower in surface water in comparison to groundwater. Microbiological water quality was better in groundwater than surface water. The DO level was found to be little bit low. A modified design of the existing EcoSan toilet was proposed to minimize the operation and maintenance difficulties in the prevailing system. In the modified design, users need not to being transferred from defecation place to anal washing place and hence would use the toilet at one sitting. Finally, it can be concluded that the EcoSan toilets have great potentials for its promising application in the context of rural Bangladesh.