Assessment of urine diverting dehydrating toilets as a flood-resilient and affordable sanitation technology in the context of Bangladesh

Bangladesh has made a significant contribution to supply improved sanitation facilities in rural areas in recent years. As it is the most known option, pit latrines were the most favourable technology. Yet, as Bangladesh is a country of flooding and high groundwater table, pit latrines not only flush out and cause pollution; they also become inaccessible during floods, and remain filled with silt after the floods. Every year floods destroy many sanitation facilities and force people to resort to open defecation, despite the capital-intensive investment. Urine Diversion Dehydration Toilets (UDDTs) were evaluated on their suitability in flood-prone areas and their affordability in the context of Bangladesh. A survey conducted in two flood-prone areas of Bangladesh showed that with an average height of 0.69 m the UDDTs are higher than the average highest flood level of 0.31 m. To decrease cost and construction complexity, a local design was developed based on the current pit latrine, at 50% of the costs of the current UDDTs. Although the resulting cost is still not within reach for most Bangladeshi, the affordability could be increased by taking into account avoided emptying costs as well as the added value of human excreta as a fertilizer.