The inadequate water supply and sanitation situation in South Tarawa has contributed to high rates of water-borne diseases and environmental degradation in the country's main urban center. There has been limited capital investment in water supply and sanitation infrastructure and ongoing operations and maintenance in South Tarawa, in part, as a result of low cost recovery in service delivery. To enable more informed policy responses to address the current situation, this study seeks to estimate the total economic costs associated with inadequate water and sanitation services in South Tarawa.

The case for investment in water, sanitation and hygiene (WASH) has been convincingly made. WASH is essential for protecting public health, is a human right and investing in it is compelling from a fiscal and economic point of view. While the estimated $114 billion per year of capital investments required to meet universal access to safely managed water and sanitation services by 2030 is often portrayed as a hefty price tag, current best estimates of benefit-to-cost ratios leave little doubt about its value. What is less clear is how to allocate resources efficiently. There is limited evidence on the cost efficiency and cost effectiveness of various policy and implementation choices. The underlying drivers of demand for (new) technologies and solutions are, for example, poorly understood, as is beneficiaries’ willingness to pay (WTP), leading to open questions about pricing policies and sustainable business models. This is in contrast to other infrastructure sectors, such as energy and transport, where active literature on the economics and financing of services has been more helpful in defining national and international policy. Our objective with this book is to encourage the WASH sector to follow suit and start to effectively engage and research these issues. At the heart of this book therefore, are chapters which highlight some of the specificities, and challenges of conducting full economic evaluations of WASH interventions, provide a deeper understanding of potential solutions, and present new findings on costs and outcome measures, thereby contributing towards a fuller picture of WASH cost-effectiveness. In Focus – a book series that showcases the latest accomplishments in water research. Each book focuses on a specialist area with papers from top experts in the field. It aims to be a vehicle for in-depth understanding and inspire further conversations in the sector.

The new 2030 Agenda for Sustainable Development includes water, sanitation, and hygiene (WASH) at its core. A dedicated Sustainable Development Goal (SDG 6) declares a commitment to "ensure availability and sustainable management of water and sanitation for all." Monitoring progress toward this goal will be challenging: direct measures of water and sanitation service quality and use are either expensive or elusive. However, reliance on household surveys poses limitations and likely overstated progress during the Millennium Development Goal period. In Innovations in WASH Impact Measures: Water and Sanitation Measurement Technologies and Practices to Inform the Sustainable Development Goals, we review the landscape of proven and emerging technologies, methods, and approaches that can support and improve on the WASH indicators proposed for SDG target 6.1, "by 2030, achieve universal and equitable access to safe and affordable drinking water for all," and target 6.2, "by 2030, achieve access to adequate and equitable sanitation and hygiene for all and end open defecation, paying special attention to the needs of women and girls and those in vulnerable situations." Although some of these technologies and methods are readily available, other promising approaches require further field evaluation and cost reductions. Emergent technologies, methods, and data-sharing platforms are increasingly aligned with program impact monitoring. Improved monitoring of water and sanitation interventions may allow more cost-effective and measurable results. In many cases, technologies and methods allow more complete and impartial data in time to allow program improvements. Of the myriad monitoring and evaluation methods, each has its own advantages and limitations. Surveys, ethnographies, and direct observation give context to more continuous and objective electronic sensor data. Overall, combined methodologies can provide a more comprehensive and instructive depiction of WASH usage and help the international development community measure our progress toward reaching the SDG WASH goals.

As the human population grows-tripling in the past century while, simultaneously, quadrupling its demand for water-Earth's finite freshwater supplies are increasingly strained, and also increasingly contaminated by domestic, agricultural, and industrial wastes. Today, approximately one-third of the world's population lives in areas with scarce water resources. Nearly one billion people currently lack access to an adequate water supply, and more than twice as many lack access to basic sanitation services. It is projected that by 2025 water scarcity will affect nearly two-thirds of all people on the planet. Recognizing that water availability, water quality, and sanitation are fundamental issues underlying infectious disease emergence and spread, the Institute of Medicine held a two-day public workshop, summarized in this volume. Through invited presentations and discussions, participants explored global and local connections between water, sanitation, and health; the spectrum of water-related disease transmission processes as they inform intervention design; lessons learned from water-related disease outbreaks; vulnerabilities in water and sanitation infrastructure in both industrialized and developing countries; and opportunities to improve water and sanitation infrastructure so as to reduce the risk of water-related infectious disease.

This paper argues that there are many challenges to designing and implementing water and sanitation interventions that actually deliver economic benefits to the households in developing countries. Perhaps most critical to successful water and sanitation investments is to discover and implement forms of service and payment mechanisms that will render the improvements worthwhile for those who must pay for them. In this paper, we argue that, in many cases, the conventional network technologies of water supply and sanitation will fail this test, and that poor households need alternative, non-network technologies. However, it will not necessarily be the case that specific non-network improved water supply and/or sanitation technologies will always be seen as worthwhile by those who must pay for them. We argue that there is no easy panacea to resolve this situation. For any intervention, the outcome is likely to be context-dependent. An intervention that works well in one locality may fail miserably in another. For any given technology, the outcome will depend on economic and social conditions, including how it is implemented, by whom, and often on the extent to which complementary behavioral, institutional and organizational changes also occur. For this reason, we warn against excessive generalization: one cannot, in our view, say that one intervention yields a rate of return of x% while another yields a return of y%, because the economic returns are likely to vary with local circumstances. More important is to identify the circumstances under which an intervention is more or less likely to succeed. Also for this reason, when we analyze a few selected water and sanitation interventions, we employ a probabilistic rather than a deterministic analysis to emphasize that real world outcomes are likely to vary substantially.

Uncharted Waters: The New Economics of Water Scarcity

Sixth edition of the hugely successful, internationally recognised textbook on global public health and epidemiology, with 3 volumes comprehensively covering the scope, methods, and practice of the discipline