Clean Water, Human Health and Sustainable Development (2008-2012, updates here)


The Water and Development Initiative seeks to identify policy solutions to help meet the pressing safe domestic water challenge that the world faces today. The Millennium Development Goals call for reducing by half the proportion of people without sustainable access to safe drinking water. This goal was adopted in large part because clean water was seen as critical to fighting diarrheal disease, which kills two million children annually. Despite this call to arms however, we know far too little about how to sustainably achieve this goal with the scarce resources that are available. Even where technical solutions are available, not enough is known about how institutions and policies can be designed to promote efficient take-up and sustained use. The Water and Development Initiative seeks to expand our knowledge base on linked human and natural systems around drinking water and provide an opportunity for productive interaction between policymakers and researchers on clean water issues. The Water and Development Initiative's activities include:

  • Measuring the health impacts of source water quality improvement, exploring consumers' valuations of these improvements, and examining the impact of alternative property rights and maintenance systems on provision of these improvements.
  • Measuring the impact and identifying ways to increase use or take-up of point-of-use water improvement solutions, in particular treatment with dilute chlorine-based solutions.
  • Evaluating the use, scalability, and sustainability of an innovative water chlorination technology, a chlorine dispenser installed at communal water points. Activities include:
    • Evaluating options for financing and managing the infrastructure over time, including through local governments
    • Collaborating with NGOs to pilot dispensers in a variety of countries and contexts
    • Working with ministries in Kenya to pilot programs through local institutions, including public schools and health clinics
  • Disseminating results to national governments and international development agencies to encourage adoption of this technology as part of water programs.

Source Water Quality Improvements

Identifying the health impacts of source water quality improvements was a central focus of researchers working in the Water and Development Initiative. This work is motivated largely by the fact that we know very little about the health impacts of source water quality improvements that may improve water quality at the point of collection but which do not obviate the need for water storage in the home prior to consumption. Research from the 1980s and 1990s on this question is methodologically weak and provides conflicting evidence on the question. In contrast, more recent and methodologically stronger work has demonstrated clearly that both piped water and water that is chemically treated in the home can deliver the large health effects that we intuitively expect. Kremer and Zwane reviewed this literature in detail as part of an effort that contributed to the development of the Water and Development Initiative.

Water and Development researchers studied source water quality improvements by evaluating a randomized phase-in of a non-profit organization program that improved water quality by protecting springs. Results showed that spring protection leads to large improvements in source water quality as measured by the fecal indicator bacteria E. coli. This translates to moderate gains in home water quality and to a one quarter fall in reported child diarrhea incidence.

We also use the willingness of consumers to travel further for cleaner water to estimate the valuation consumers place on cleaner water and simulate the implications of alternative systems of property rights in water sources. We examine the Kenyan context's existing social norms and legal institutions requiring landowners to provide neighbors with free access to drinking water yield superior welfare than would alternative private property institutions, despite providing weaker incentives for investment in water infrastructure. However, alternative, mixed systems could potentially offer superior performance.

Closely linked to the challenge of increasing and sustaining technology adoption in this sector is the challenge of making investments financially sustainable. Infrastructure maintenance has historically been a major problem in developing countries and in the water sector, in particular.

A standard model for maintaining donor-funded infrastructure projects in rural areas of developing countries is to establish user groups composed of members of the community that are responsible for project maintenance and management. This institutional design is expected to result in improved (financial) sustainability and quality of public services, while reducing the need for on-going donor funding or involvement. Despite donor interest in such schemes, there is little convincing empirical evidence that local user committee management of public goods-such as improved drinking water sources-results in either greater financial sustainability or better quality service. We are evaluating alternative institutional structures for rural water infrastructure maintenance, including efforts to empower women in management structures and the structure of financial incentives for good performance.

We plan to evaluate whether improving the policy environment can lead to increased access to dual-use infrastructure, which provides water for irrigation in addition to domestic use. Preliminary results suggest that changing financing mechanisms, by moving from system in which loans for the infrastructure were backed by guarantors to one in which the infrastructure itself served as collateral for the loan, significantly spurred demand for the technology without leading to unacceptable default levels. We continue to conduct work to understand the impact of increased quantities of domestic water on health behavior (e.g., washing) and health.

Point-Of-Use (POU) Treatment

Medical and public health researchers have demonstrated important health gains from point-of-use water treatment, which may help address issues of contamination of water in transport and storage that were found to be significant limitations on the efficacy of source water quality improvements. However, outside of the artificial research setting, the health benefits of many interventions depend on individual decisions to adopt and consistently adhere to certain behaviors. The observed impacts for in-home water treatment are generated in settings where high uptake (around 70 percent in the case of point-of-use water treatment) is supported by weekly or daily reminders by fieldworkers. Such high-intensity contact with fieldworkers is prohibitively expensive to provide on a large-scale basis. The challenge of increasing uptake is further complicated by infectious disease externalities; because the private benefits of product use are smaller than the social benefits, to the extent that private uptake affects the communal disease environment, inefficiently low levels of adoption can be expected even at subsidized product prices.

Water and Development researchers are investigating various strategies for inducing take-up of in-home or POU water treatment technologies that leverage existing retail models of product distribution. Preliminary results suggest that demand for such technologies is extremely sensitive to price and that providing them for free can greatly increase take-up. Either individual or community health-related messages do little to increase demand, but employing a community member to promote water treatment increases take-up significantly in the medium term. Insights from this research could enable future marketing campaigns to increase adoption and sustained use of POU water treatment products.

We are also investigating alternatives to the retail distribution model. One alternative that researchers are examining is a newly developed village-level distribution system to promote the adoption and sustained use of simple water treatment technologies. Communal dispensers for water treatment were developed to help overcome barriers uncovered by our previous research-cost, salience, convenience, and social learning-and overcome the scalability and sustainability problems that hinder alternative strategies for increasing use of related products in the home. Preliminary results suggest that dispensers have tremendous potential to increase take-up of water treatment, with take-up increasing almost 8-fold when communities had access to dispensers as compared to the retail model for distributing POU products. We hope to evaluate why communal dispensers have achieved these high rates of take-up.

Water and Development researchers will also investigate a second alternative distribution mechanism in which water treatment products are distributed at ante-natal clinics where mothers with young children are accessing other health care services.

A third approach is our delivering in-home treatment products and encouragement of hand-washing via schools. We will explore the potential for this to change water treatment and hand-washing behavior at home. We will also explore the extent to which schools can be effective as a vehicle for transmission of health information and behavior change, and the extent to which children can act as agents of change for household health behaviors, particularly water treatment.

Strategies for Sustainable Provision of Water Treatment Infrastructure at Scale: Chlorine Dispensers

A simple new technology, chlorine dispensers, that was developed as part of earlier work in the Water and Development Initiative, provides a way to chlorinate drinking water when it is collected at a communal water source. In pilots in Western Kenya, dispensers have achieved break-through take-up rates of between 60 to 70 percent, as compared to less than 10 percent in the control group with access to chlorine via the retail channel. Dispensers are also an extremely low-cost way to provide chlorine, since they significantly reduce packaging and transport costs (which make up the bulk of the cost of packaged chlorine solution). The long-term cost of providing chlorine through dispensers is expected to be only a quarter to half the cost of chlorine sold via more traditional retail distribution. The dispenser system is also very cheap, costing as little as $0.15 per person per year at scale, or between a quarter and a third of the cost of retail delivery of chlorine for in-home use. The cost per Disability-Adjusted Life Year (DALY) saved would be less than $20 per year, which is comparable to vaccinations. High take-up rates, low costs, and ease of maintenance all suggest a high potential to scale. A major thrust of activities for 2009-2011 how this particular approach to water treatment can be financed, distributed, and maintained in a way that is scalable and sustainable.

We will investigate various financing approaches including options along the spectrum from free public provision to market models with full cost recovery, including mixed models with partial cost recovery. We will also test different approaches to decentralized management of this public good. We also plan to investigate the details of financing mechanisms as well as opportunities for financing water infrastructure through local governments, who in many parts of the developing world receive budgets to finance local development activities.

We will also be attempting to scale up chlorination through dispensers by institutionalizing it as part of local public institutions in Kenya, including an ongoing pilot program in schools funded by the Ministry of Education in Kenya. We are also exploring opportunities to incorporate this in local government programs and in central governments' public health apparatus. We are also working on understanding the global potential for chlorine dispensers via pilots in collaboration with NGOs in different contexts across multiple countries.

Outreach and Impact

The project is having a major policy impact. In addition to the initial The Bill and Melinda Gates Foundation 3.3 million dollar grant, an additional 816,000 dollar grant has been provided by the Bill and Melinda Gates Foundation to implement Dispensers with four partner organizations - Oxfam/America, Oxfam/Great Britain, IFRC, and IRC - in emergencies. Additionally, USAID is considering a 5 million dollar grant for scaling-up Dispensers outside of Kenya. The Bill and Melinda Gates Foundation is supporting including chlorine dispensers in health impact trials in Kenya and in Bangladesh. In Bangladesh, 1,350 Dispensers have been installed, with another 5,200 to be installed. Dispensers are serving more than 300,000 people in Kenya, Haiti, and Bangladesh.
The Kenyan Ministries of Water, Education, and Public Health and Sanitation have all supported and financed dispenser installations, to bring safe water to rural communities.

Key Research Findings:

Spring Cleaning: Rural Water Impacts, Valuation and Property Rights Institutions uses a randomized evaluation to measure the health impact of improving water sources through spring protection. Spring protection seals off the spring and encases it in concrete so that water flows out of a pipe, as opposed to seeping from the ground, where it is vulnerable to contamination when people dip vessels to scoop out water and when runoff introduces human or animal waste into the area. The study found that spring protection led to a 66% reduction in fecal contamination at the water source, but the reductions were only 24% in water stored in people’s homes, due to recontamination.

Providing Safe Water: Evidence from Randomized Evaluations uses a public economics framework to review evidence from randomized trials on domestic water access and quality in developing countries and to assess the case for subsidies. Water treatment can cost-effectively reduce reported diarrhea. However, many consumers have low willingness to pay for cleaner water; few households purchase household water treatment under retail models. Free point-of-collection water treatment systems designed to make water treatment convenient and salient can generate take-up of approximately 60% at a projected cost as low as $20 per year of life saved, comparable to vaccine costs. In contrast, the limited existing evidence suggests that many consumers value better access to water, but it does not yet demonstrate that better access improves health. The randomized impact evaluations reviewed have also generated methodological insights on a range of topics, including (a) the role of survey effects in health data collection, (b) methods to test for sunk-cost effects, (c) divergence in revealed preference and stated preference valuation measures, and (d) parameter estimation for structural policy simulations.

Water and Development related projects at Harvard:

Creating a Conservation Ethic: The Effect of Education, Incentives and Enforcement on the Formation of Social Norms
Nava Ashraf

The Influence of Wellwater Arsenic on Marriage And Child Health Outcomes in Bangladesh
Erica Field

Measuring Willingness to Pay for Improved Water Quality at the Source
Michael Kremer

Encouraging Take-Up of Point of Use Water Treatment Products
Sendhil Mullainathan

Evaluating the Impact of Rural Water Interventions
Michael Kremer

The impact of Rainfall Shocks on Cooperation and Productivity in Contract Farming: Evidence from Kenya
Michael Kremer, Sendhil Mullainathan