Challenges and Potentials of Ecological Sanitation: Experiences from the Cases in Vietnam and Malawi

Abstract

The world’s sanitation systems must be up to the challenge of addressing the global crises of water shortages and food insecurity in the face of a growing population. To help address these problems, ecological sanitation (Ecosan), which typically involve the use of urine-diverting dry toilets (UDDTs) and the application of excreta in agriculture, can be employed. This paper discusses the challenges and potentials of the Ecosan approach in terms of 3 essential requirements—continuous defecation use, reduction of health risk, and use of excreta—by examining 3 cases of Ecosan use in Vietnam and Malawi. The experience with traditional Ecosan in rural Vietnam suggests that dry sanitation practices that apply Ecosan are effective at reducing fecal contamination in the surrounding water environment, thereby reducing the health risk from unavoidable accidental ingestion of contaminants. However, current sanitization processes involving the application of manure to agricultural products represent a significant health risk challenge. The experience with modern UDDTs in rural Vietnam suggests that they can be continuously used for defecation for long periods of time without intervention, while there remain major challenges to continuous use from physical damage to the UDDT structures. The proper management of fecal chambers can successfully control the offensive odors that are a source of wide concern. In rural Malawi, the introduction of modern UDDTs successfully fostered a demand for the use of feces by raising the perception of its value in agriculture and through an integration of the Ecosan project into an agricultural technology transfer program. Urine use, by contrast, did not gain a wide acceptance, suggesting that raising an awareness of the effects of urine on agriculture is a key challenge. Thus, although some challenges still need to be overcome, 3 cases of Ecosan showed bright potentials of the Ecosan approach from the 3 essential requirement.