One of the UN Millennium Goals is to halve by 2015 the proportion of people without sustainable access to safe drinking water and basic sanitation. We know that large-scale investments in piped water have dramatic impacts on reducing childhood mortality. Piped water, however, may be prohibitively expensive for the nations to provide to rural residents in low-density areas. Thus, we need to find clean water alternatives for the 926 million people without access to a clean water source who are living in the rural areas of developing countries.
According to a paper by Iyer et al. 2006, nearly all of the $5.5 billion the World Bank invested in rural water and sanitation programs during 1978–2003 focused on improving water supply sources and quality through interventions such as well digging. During my time in El Salvador, many of the NGOs there were digging wells to provide clean water to the residents.
A recent NBER working paper by Alix Peterson Zwane and Michael Kremer, however, suggests that well digging is not an effective means to reduce diarrheal diseases. This diarrheal diseases kill over 2 million children in developing countries each year. One of the major reasons for this are the significant maintenance costs which need to be incurred each year in order keep the well functioning. In fact, one third of rural water infrastructure in South Asia is believe to be not functional. Other studies found that more effective rural interventions included: exclusive breastfeeding, immunization, oral rehydration therapy, micronutrient supplementation, point-of-use water treatment systems, and increased hand washing.
Careful evaluation of future clean water initiatives is necessary in order that money spent on infrastructure in the developing world is used in the most effective manner possible.