A sustainable approach towards rural development: dry toilets in Nepal

Existing inadequate sewerage systems and direct disposal of household waste into water courses has tremendously increased water pollution. Dry toilets are feasible in rural and peri-urban areas to reduce the consumption of costlier water that is required for flushing. As conventional treatment technologies require high investment, and operation and maintenance costs, dry toilets are the only suitable option left for sanitation in the 21st century when working with limited financial resources. To reduce environmental degradation and overcome this problem, the dry toilet is only the realistic option in Nepal. Two reactors, one exposed to sunrays and the other without sunrays, were constructed. In the model with sunrays, it was found that in 48 days of observation faecal coliform presence depleted to 610 cells per gm from the initial value of 7 x 10(10) and volatile organic matter came down from 98.09% to 70.18%. Similarly, in the other model, the destruction of faecal coliform in 65 days was found to be 920 cells/gm while the destruction of organic matter took 75 days. Also, observing from 313 people in a cluster on the pilot project, the annually recovered value of N, P and K was found to be 1565 kg, 125 kg, 344 kg, respectively. This paper deals with the different types of dry ecological toilet, their performance and feasibility study in Nepal, with the full involvement of local people, based on complete laboratory analysis and regular monitoring. Using dry toilets will save 14 LPCD, which is equivalent to 14 MLD and the resulting demand will become only 80 MLD for the urban area of Kathmandu. The result advocates the implementation of ecological dry toilets to save valuable water wasted in flushing, as well as saving the resources needed to treat the waste.