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Third Copenhagen Consensus: Water and Sanitation Assessment, Rijsberman Zwane

An Assessment Paper on Water and Sanitation has been written by Frank Rijsberman and Alix Zwane and released by the Copenhagen Consensus Center. The working paper used by the Expert Panel is available for download here, the finalized paper has been published in Global Problems, Smart Solutions - Costs and Benefits by Cambridge University Press.

In addition two Perspective Paper have been released, one by by W. Michael Hanemann, as well as one by Guy Hutton.

Short summary

The world has met the Millennium Development Goal on the provision of clean drinking water five years early, but is set to miss its goal on basic sanitation by almost 1 billion people. An astonishing one-third of the world population, 2.5 billion people, lack access to basic sanitation and over one billion people defecate out in the open.

Inadequate sanitation caused a cholera outbreak in Haiti in late 2010 that has now made half a million people sick and cost some 7000 lives; smaller cholera outbreaks are still commonplace during the rainy season in Bangladesh or the low-lying parts of many Africa cities. Diarrheal diseases are still a leading cause of death for children under five, second only to respiratory infections. The World Bank concludes that the economic impact of poor sanitation can be as high as 7% of GDP for some Asian countries and on the order of 1-2% of GDP for African countries.

Copenhagen Consensus 2012 asked Frank Rijsberman and Alix Peterson Zwane from the Gates Foundation to establish the best ways to reduce the size of this challenge.

Development agencies over-emphasize safe water projects and under-invest in sanitation, according to Rijsberman and Zwane. They look at what it would cost to improve service for both the unserved population in developing countries, those one billion or so who must defecate in the open, and what it would cost to improve the quality of service for those people in urban areas who are nominally “served” but struggle to realize the gains from sanitation because of the challenges of emptying and safely disposing of latrine or septic tank contents.

An estimated 200 million latrines and septic tanks is emptied manually, by a worker descending in the pit with a bucket and spade, and subsequently dumped or buried in the immediate environment – often reintroducing pathogens previously contained in the pit or tank.

They propose three solutions as potentially worthy of large scale investment.

The first of these is ‘Community Led Total Sanitation’, the name given to various forms of an approach that emphasizes behavior change, particularly the community’s responsibility to share in the creation of open defecation free communities, particularly in rural areas. Rijsberman and Zwane specifically propose a large-scale program, reaching 23 million with a one-off delivery cost of $3-5 per person affected.

Given the rapid adoption of community-led total sanitation programs at a scale of tens of millions of people over the last ten years, and the relatively high rate of success in achieving ‘open defecation free’ communities, they consider this to be a comparatively low-risk intervention.

Their analysis implies that about 50 percent or 600 million people in rural areas that lack access to basic sanitation could be reached with an investment of US$3 billion, providing welfare benefits that are 4-7 times higher.

The second intervention they explore is ‘Sanitation as a Business’. A critical bottleneck for the existing over two billion latrines and septic tanks in developing countries, affecting particularly the urban poor, is that there are no affordable and sustainable services to effectively and efficiently empty them and process the fecal sludge safely and economically. Typically, the sludge is just deposited on the ground, negating almost all of the health benefits. Their solution is to generate innovation in sanitation services,  reducing the cost to just $10 per household per year and that consists of emptying the latrine or septic tank, transporting the fecal sludge to a treatment plant, and treating it to acceptable levels prior to reuse and/or dispersal into the environment. While speculative, they provide illustrative calculations that suggest that an investment in innovation to develop these technologies, including an initial subsidized roll out, would provide benefits to some 40 million people at a cost of $320 million and a BCR of 27-46.

Thirdly, Rijsberman and Zwane propose ‘The Reinvented Toilet’ – one of the signature ideas of the Gates Foundation: efforts to stimulate technical innovation, particularly harnessing advances in physics, chemistry, and engineering, to create a radically reinvented toilet that recycles human waste into reusable products at the household scale.

Early in 2011 the Bill & Melinda Gates Foundation challenged over 20 top universities around the globe to use modern science and engineering to come up with a radically different form of processing and recycling human waste that does not depend on sewers networks and large volumes of water for transportation. The challenge was to develop a system that is: off the grid, affordable for the poorest members in society (less than .05/day), and an aspirational product – something everyone will want to use and that over time replaces the flush toilet as the new gold standard. The foundation has awarded eight Reinvent the Toilet Challenge grants and funded another 57 small grants in 2011 that all aim to innovate all or part of the non-sewered value chain. All complete reinvented toilets are currently at the laboratory / proof-of-concept to prototype stage and therefore investments in the development of this solution are high risk. The foundation expects to review the first series of prototypes and proof-of-concept results for parts and processes in August 2012.   

Assuming that this investment would lead to 100 percent coverage for all latrines currently emptied manually, this $125 million investment, would pay back $40 for each invested dollar, serving 1 billion people. In addition, if successful, the Reinvented Toilet would serve many more people of the other 3.5 billion people who currently don’t have access to a flush toilet. Presuming a reinvented toilet can be successfully developed, and can become an aspirational product – the smartphone of sanitation – the issues of high cost, slow adoption and limited benefits that variously plague the current generation of sanitation technologies will be overcome.