Rural Sanitation Sustainability Dynamics: Gaining Insight through Participatory and Simulation Modeling.

Improved sanitation provides many benefits to human health and well-being and is integral to achieving Sustainable Development Goal Six. However, many nations, including most of sub-Saharan Africa, are not on track to meeting sanitation targets. Recognizing the inherent complexity of environmental health, we used systems thinking to study sanitation sustainability in Uganda. Our study participants, 37 sanitation actors in three rural districts, were engaged in interviews, group model building workshops, and a survey. The resulting model was parametrized and calibrated using publicly available data and data collected through the Uganda Sanitation for Health Activity. Our simulations revealed slippage from improved sanitation in all study districts, a behavior reflected in real interventions. This implies that systemic changes-changes to the rules and relationships in the system-may be required to improve sanitation outcomes in this context. Adding reinforcing feedback targeting households' perceived value of sanitation yielded promising simulation results. We conclude with the following general recommendations for those designing sanitation policies or interventions: (1) conceptualize sanitation systems in terms of reinforcing and balancing feedback, (2) consider using participatory and simulation modeling to build confidence in these conceptual models, and (3) design many experiments (e.g., simulation scenarios) to test and improve understanding.

Do Sanitation Marketing Activities Increase Households' Likelihoods of Reaching Improved Sanitation or Involving Women in Decision Making?

Poor sanitation causes 30% of diarrheal deaths globally, and much of the world has struggled to finance top-down interventions. Sanitation marketing is a demand-led approach that uses a mixture of social and commercial marketing methods and direct sales to households. However, little is known about its impacts on household decision making. This mixed-methods study uses data from eight focus groups and 86,666 household surveys from participants in a five-year sanitation marketing program in Uganda. Logistic regression models identified 10 variables predicting attainment of improved (limited or basic) sanitation and four variables predicting female involvement in decision making. Triggering session attendance increased chances of reaching improved sanitation by 15-28%, depending on who attended, and by 19% if the household found the session motivational. Although women were engaged in decision-making conversations, they were not viewed as primary decision makers, even in female-headed households. Women were more likely to become involved in decision making if they had attended triggering sessions with men (+70%) or engaged with sales promoters alone (+74%) or with men (+78%). For both outcomes, joint activity engagement was more effective than male or female engagement alone. This work highlights two sanitation marketing activities as pathways to improving latrine coverage and women's decision-making agency.

Systems Thinking for Effective Interventions in Global Environmental Health.

Environmental health risks such as household air pollution due to burning solid fuels, inadequate water, sanitation, and hygiene, and chemical pollution disproportionately affect the poorest and most marginalized populations. While billions of dollars and countless hours of research have been applied toward addressing these issues in both development and humanitarian contexts, many interventions fail to achieve or sustain desired outcomes over time. This pattern points to the perpetuation of linear thinking, despite the complex nature of environmental health within these contexts. There is a need and an opportunity to engage in critical reflection of the dominant paradigms in the global environmental health community, including how they affect decision-making and collective learning. These paradigms should be adapted as needed toward the integration of diverse perspectives and the uptake of systems thinking. Participatory modeling, complexity-aware monitoring, and virtual simulation modeling can help achieve this. Additionally, virtual simulation modeling is relatively inexpensive and can provide a low-stakes environment for testing interventions before implementation.

Pathways for collaboratively strengthening water and sanitation systems.

Collaborative approaches are seen as a promising way to strengthen Water, Sanitation, and Hygiene (WASH) service delivery systems when challenges exceed the mandates and capabilities of any single entity. While collaborative approaches are well studied in high-income country contexts, current understanding of their application to international development contexts is limited. This paper uses fuzzy-set Qualitative Comparative Analysis to assess what conditions and pathways drove or impeded progress within eleven collaborative approaches for WASH service delivery in Eastern Africa. Evidence supported three main findings: (1) Government uptake of recommendations is necessary for progress but cannot be guaranteed solely by government participation in the collaboration, (2) different forms of problem identification are possible; problem scopes are often predefined to align with funders and partner government agendas, but flexible scopes that foster collective problem identification can reap benefits, and (3) hub convening power can be critical and convening power can be gained in different ways. Political dynamics, shifting priorities, and turnover undermine collaborative efforts, but collaborative approaches can still make progress in spite of turnover if funds are available for implementation of activities (i.e. in addition to funds for meetings and hub roles) and program implementers either facilitate collective problem identification or establish a hub with convening power. Yet even these tactics are vulnerable to instability, thus in highly unstable contexts, stakeholders and funders should be realistic from the outset about what they may be able to achieve. Building on existing theories of collaborative approaches, this work revealed that there is no single best design for collaborative approaches in WASH, rather, core elements worked together in different ways depending on the context.

Sand Barriers around Latrine Pits Reduce Fecal Bacterial Leaching into Shallow Groundwater: A Randomized Controlled Trial in Coastal Bangladesh.

We evaluated the effectiveness of a sand barrier around latrine pits in reducing fecal indicator bacteria (FIB) leaching into shallow groundwater. We constructed 68 new offset single pit pour flush latrines in the Galachipa subdistrict of coastal Bangladesh. We randomly assigned 34 latrines to include a 50 cm thick sand barrier under and around the pit and 34 received no sand barrier. Four monitoring wells were constructed around each pit to collect water samples at baseline and subsequent nine follow-up visits over 24 months. Samples were tested using the IDEXX Colilert method to enumerate E. coli and thermotolerant coliforms most probable number (MPN). We determined the difference in mean log10MPN FIB counts/100 mL in monitoring well samples between latrines with and without a sand barrier using multilevel linear models and reported cluster robust standard error. The sand barrier latrine monitoring well samples had 0.38 mean log10MPN fewer E. coli (95% CI: 0.16, 0.59; p = 0.001) and 0.38 mean log10MPN fewer thermotolerant coliforms (95% CI: 0.14, 0.62; p = 0.002), compared to latrines without sand barriers, a reduction of 27% E. coli and 24% thermotolerant coliforms mean counts. A sand barrier can modestly reduce the risk presented by pit leaching.

Lead (Pb) contamination of self-supply groundwater systems in coastal Madagascar and predictions of blood lead levels in exposed children.

Thousands of households in coastal Madagascar rely on locally manufactured pitcher-pump systems to provide water for drinking, cooking, and household use. These pumps typically include components made from lead (Pb). In this study, concentrations of Pb in water were monitored at 18 household pitcher pumps in the city of Tamatave over three sampling campaigns. Concentrations of Pb frequently exceeded the World Health Organization's provisional guideline for drinking water of 10 µg/L. Under first-draw conditions (i.e., after a pump had been inactive for 1 h), 67% of samples analyzed were in excess of 10 µg/L Pb, with a median concentration of 13 µg/L. However, flushing the pump systems before collecting water resulted in a statistically significant (p < 0.0001) decrease in Pb concentrations: 35% of samples collected after flushing exceeded 10 µg/L, with a median concentration of 9 µg/L. Based on measured Pb concentrations, a biokinetic model estimates that anywhere from 15% to 70% of children living in households with pitcher pumps may be at risk for elevated blood lead levels (>5 µg/dL). Measured Pb concentrations in water were not correlated at statistically significant levels with pump-system age, well depth, system manufacturer, or season of sample collection; only the contact time (i.e., flushed or first-draw condition) was observed to correlate significantly with Pb concentrations. In two of the 18 systems, Pb valve weights were replaced with iron, which decreased the observed Pb concentrations in the water by 57-89% in one pump and by 89-96% in the other. Both systems produced samples exclusively below 10 µg/L after substitution. Therefore, relatively straightforward operational changes on the part of the pump-system manufacturers and pump users might reduce Pb exposure, thereby helping to ensure the continued sustainability of pitcher pumps in Madagascar.