Mikael Mangold

Prevalence of microbiological contaminants in groundwater sources and risk factor assessment in Juba, South Sudan

In low-income regions, drinking water is often derived from groundwater sources, which might spread diarrheal disease if they are microbiologically polluted. This study aimed to investigate the occurrence of fecal contamination in 147 improved groundwater sources in Juba, South Sudan and to assess potential contributing risk factors, based on bivariate statistical analysis. Thermotolerant coliforms (TTCs) were detected in 66% of the investigated sources, including 95 boreholes, breaching the health-based recommendations for drinking water. A significant association (p<0.05) was determined between the presence of TTCs and the depth of cumulative, long-term prior precipitation (both within the previous five days and within the past month). No such link was found to short-term rainfall, the presence of latrines or damages in the borehole apron. However, the risk factor analysis further suggested, to a lesser degree, that the local topography and on-site hygiene were additionally significant. In summary, the analysis indicated that an important contamination mechanism was fecal pollution of the contributing groundwater, which was unlikely due to the presence of latrines; instead, infiltration from contaminated surface water was more probable. The reduction in fecal sources in the environment in Juba is thus recommended, for example, through constructing latrines or designating protection areas near water sources. The study results contribute to the understanding of microbiological contamination of groundwater sources in areas with low incomes and high population densities, tropical climates and weathered basement complex environments, which are common in urban sub-Saharan Africa.

Quantification of Goods Purchases and Waste Generation at the Level of Individual Households

Quantifying differences in resource use and waste generation between individual households and exploring the reasons for the variations observed implies the need for disaggregated data on household activities and related physical flows. The collection of disaggregated data for water use, gas use, electricity use, and mobility has been reported in the literature and is normally achieved through sensors and computational algorithms. This study focuses on collecting disaggregated data for goods consumption and related waste generation at the level of individual households. To this end, two data collection approaches were devised and evaluated: (1) triangulating shopping receipt analysis and waste component analysis and (2) tracking goods consumption and waste generation using a smartphone. A case study on two households demonstrated that it is possible to collect quantitative data on goods consumption and related waste generation on a per unit basis for individual households. The study suggested that the type of data collected can be relevant in a number of different research contexts: eco-feedback; user-centered research; living-lab research; and life cycle impacts of household consumption. The approaches presented in this study are most applicable in the context of user-centered or living-lab research. For the other contexts, alternative data sources (e.g., retailers and producers) may be better suited to data collection on larger samples, though at a lesser level of detail, compared with the two data collection approaches devised and evaluated in this study.

Contextualizing Sustainable Development for Small Scale Water and Sanitation Systems in Cochabamba, Bolivia

Water and sanitation are pressing issues for the urban poor in Bolivia where the lack of safe water and sanitation services contributes to urban poverty. This paper defines sustainable development (SD) in relation to small scale water and sanitation systems in the metropolitan area of Cochabamba, Bolivia. A case study on the water and sanitation systems of two housing cooperatives is performed. By involving all the concerned stakeholders this study aims to identify a contextualized definition of SD, which can be used in order to assess and steer the development of small scale water and sanitation systems in the metropolitan area of Cochabamba. The identified definition consists of the following criteria, referred to as key issues: social context, socio-political factors, target group, freshwater resources, economic obstacles, reproducibility, knowledge, management, reliability, water quality and disposal. Three main challenges are identified to have had major influence on the contextualization of the SD concept: which stakeholders that are included, how the differing opinions among the stakeholders are addressed and how active the stakeholders are in the development process.