More than 2.5 billion lack basic sanitation. We can fix that.

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The story of water and sanitation is one of success and failure. 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, lacks access to basic sanitation. More than 1 billion people must defecate out in the open rather than using the toilets that we take for granted in the developed world.

Inadequate sanitation is much more than an inconvenience. It costs lives. It caused a cholera outbreak in Haiti in late 2010 that has now made 500,000 people sick and killed 7,000. Smaller cholera outbreaks are still commonplace during the rainy season in Bangladesh and the low-lying parts of many African cities. Diarrheal diseases are still a leading cause of death for children under 5, second only to respiratory infections. The World Bank concludes that the economic impact of poor sanitation can be as high as 7 percent of GDP for some Asian countries and close to 1 to 2 percent 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. Their research paper is out today.

They found that development agencies overemphasize safe-water projects and underinvest in sanitation. Rijsberman and Zwane look at what it would cost to improve sanitation services for both the unserved population in developing countries (those 1 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 are confronted with the challenges of emptying and safely disposing of latrine or septic tank contents.

An estimated 200 million latrines and septic tanks are emptied manually, by a worker descending into 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 making it the community’s responsibility to share in the creation of communities that are free from open defecation, particularly in rural areas. Rijsberman and Zwane base their calculations on a large-scale behavior-change program, reaching 23 million with a one-off delivery cost of $3 to $5 per person affected.

Given the rapid adoption of community-led total-sanitation programs aiding tens of millions of people over the last 10 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 of people in rural areas—about 600 million people— who lack access to basic sanitation could be reached with a total investment of $3 billion, providing welfare benefits that are four to seven times higher.