Public Health and Social Benefits of at-house Water Supplies, 2013. DfID.
Authors – Barbara Evans, et al.
Abstract – We carried out a mix of secondary and primary research to examine the hypothesis that access to an at-house water supply will deliver significantly greater health, social and economic benefits than those derived from a shared public water supply. Our research was based on a mix of literature review and field-base case studies. Fieldwork was carried out in three countries; Ghana, South Africa and Vietnam and used a mix of data collection methods, specifically a three-part household questionnaire, which included anthropometric measures and the measurement of water collection journeys, natural group discussions, and contextual checklists.
The relationship between water source, water usage and health and social outcomes is complex and mitigated by a range of contextual and intermediate factors. A fundamental challenge in comparing outcomes of at-house supplies with shared supplies lies with wealth as a confounder. In our analysis we were able to account for wealth effects to some extent because of the detailed household information we were able to collect. Nonetheless these challenges are significant.
In our research we focused on a two-step approach, looking at the relationship between distance to source and volumes of water consumed followed by an analysis of volumes of water carried/consumed and the health and social outcomes including hygiene practices. In this way we reduced the effect of wealth and other broader social contextual factors in the analysis. This was supplemented by the analysis of the relationship between source-type and water quality.
From our field data a strong theme was that households often used multiple water sources. This dimension of water usage has received only limited attention from researchers. It is likely that the use of multiple sources of water for different activities is a significant confounder and one of the reasons why research into the relationships between health outcomes and use of specific water sources has been inconclusive. We found a strong link between volumes of water consumed and the at-home-off-plot break point in services, but limited evidence of a distance-volume relationship once households were using off-plot supplies. We also found some evidence to suggest that where reliability of services is poor, the location of the water source may be less
significant than its performance characteristics.
In our study locations we found some evidence of households who access water from both private and public wells collecting higher quantities of water than users who access water from taps. Similarly we found strong evidence of a ‘break point’ in health outcomes between those who carried or who had previously carried water from outside the house and those who did not, relating to musculo-skeletal effects. Water quality was significantly better for those with piped water at home than those who carried water from elsewhere and stored it at home. The evidence on social benefits was limited but points to possible advantages to families who do not have to spend time carrying water but can spend time in leisure activities.
Overall the results from our research indicate that evidence for the detailed water quantity versus distance to source curve previously suggested is tenuous. The conclusion that at-house supplies are associated with higher consumption and health and social benefits is supported, but there is no evidence for the secondary drop in consumption at a fixed distance from home. In reality it seems most likely that the relationship between distance to source and volumes of water consumed is highly mediated by social and geographical factors. This suggests the quantity-distance curve is likely to be ‘displaced’ upwards or downwards in different contexts.
The headline conclusion from our research is that at-home water supply has significant, measurable benefits when compared with shared water supply outside the home provided that the service provided is reliable enough to ensure access to adequate quantities of water when required. Reliable at-home water supply results in higher volumes of water consumed, greater practice of key hygiene behaviours, a reduction in musculo-skeletal impacts associated with carrying water from outside the home, and improved water quality. This suggests a logical policy shift towards the promotion of reliable household access as the international benchmark for water supply.
For many governments, the implications of this are relatively simple. Where most people have access to reasonable quantities of water close to the home, there is a strong and compelling argument to focus investment in getting reliable water supplies into the home. In such cases, the outstanding challenges relate to improving our understanding of the relative risks associated with different dimensions of levels of service. For example, under what circumstances does a tap in the house have significant benefits over a tap in the yard? What is the relative risk associated with intermittent supply or low pressure of at-house piped supplies compared with private wells or shared supplies, if the latter can provide a more reliable service? A pressing gap in the literature relates to the water resources and cost implications of providing 24 hour supply in piped systems.
For some countries however, the challenge of moving to household supply as the benchmark level of service is more significant and will take time. In these locations (typically arid regions with limited water resources and limited access to capital funds) the policy emphasis may change more slowly. The clear policy message is that investments in water supply should be designed to enable a progressive move towards provision of household supplies even if this level of service cannot be achieved immediately. This might mean for example, designing point-source systems in such a way as to facilitate the addition of networks and house connections at a later date. In the post-2015 era, the available evidence suggests that access to reliable water supply at home should be the benchmark for water supply.