Faecal sludge containment characteristics and their implications on safe desludging in unplanned settlements of Dar es Salaam, Tanzania.

In unplanned urban settlements, where onsite sanitation systems are the norm, desludging of faecal sludge (FS) containments is a necessity because of the lack of land space to enable new construction. Poorly designed toilet facilities however may jeopardize the progress towards attainment of safely managed sanitation. This study examined FS characteristics and containment design and their effect on safe desludging with a case of two selected unplanned settlements of Dar es Salaam, Tanzania. The analysis focused on design features for the strength of the containment, access to the containment, and desludging characteristics of the FS. The Desludgeability potential of FS was determined on basis of flow behaviour explained in terms of moisture content and volatile solids. Research results showed that partially lined pits, lack of containment access holes and solid wastes are design and usage features which negatively affect containment strength and potential for safe desludging. The analysis further found that, only 54.8% of containments studied have FS that can be desludged by either mechanized or hand pumps. Pour flush toilets and septic tanks indicated a slightly higher potential for safe desludging compared to traditional pit latrines, however, the difference is not statistically significant (P = 0.180). Thus, safe desludging is a problem across all types of containments. To enhance safe desludging in Dar es Salaam, three key design features and usage ought to be urgently addressed: first, a requirement to ensure that all pits are fully lined inside, second, the mandatory presence of an access hole for FS desludging and third, limitations on solid waste entering the pits.

Contributing to the debate on categorising shared sanitation facilities as 'unimproved': An account based on field researchers' observations and householders' opinions in three regions, Tanzania.

BACKGROUND: Health risks associated with poor sanitation behaviours continue to be reported mostly from low-income countries (LICs). Reports show that various factors limit many people from accessing and using improved latrines, forcing some to opt for sharing latrines with neighbours, others practicing open defecation. Meanwhile, debate prevails on whether shared latrines should be categorised as unimproved according to WHO/UNICEF-JMP criteria. We contribute to this debate based on results from a study undertaken in three regions, Tanzania. MATERIALS AND METHODS: Data were collected through observations in 1,751 households with latrines, coupled with collection of opinions from heads of such households regarding the latrine-sharing practices. Bivariate and multivariate logistic regression analyses were performed to assess associations between the outcome and possible predictor variables. RESULTS: Of all 1,751 latrines, 14.6% were shared. Among the shared latrines, 74.2% were found being generally clean as compared to 69.2% of the non-shared ones. Comparing the shared and non-shared latrines, the non-shared latrines were significantly less likely to be found with floors built with permanent materials (OR = 0.73, 95% CI: 0.55, 0.98); washable floors (OR = 0.69; 95% CI: 0.51, 0.93); and lockable doors (OR = 0.73; 95% CI: 0.56, 0.95). Shared latrines were less likely to have floors with faecal matter, functional handwashing facilities (HWFs), HWFs with running water, and roofs; albeit the differences in all these scenarios were not statistically significant. Respondents expressed desire for improved latrines, but also did not find it wrong to share latrines if cleanliness was maintained. CONCLUSION: Having an 'improved' latrine remains important as JMP recommends, but based on our study findings, we argue that possessing a non-shared latrine neither guarantees safety to its users nor its categorisation as 'improved'. Instead, the state of the latrine, the construction technology used and the behaviours of the users may be more important.