Turning Pipe Dreams into Reality: Maximizing the Impact of Sanitation and Water Pipe Infrastructure through Connection Subsidies and Life Skills Training

October 3, 2016

In Kenya researchers will study a program to improve access to water and sanitation along with a social hygiene campaign. In addition to studying how much villagers are willing to pay for sanitation services, this evaluation will help experts in Kenya and elsewhere learn how to encourage behavioral changes that improve water quality and health.

In 1977, the international community declared the 1980s the “International Drinking Water Supply and Sanitation Decade.” The goal was to ensure that everyone in the world would have access to clean water and sanitation by the end of the decade. Nearly four decades later, development experts and governments are still struggling to reach these targets. The new deadline is 2015, by when the Millennium Development Goals have said that at least 88 percent of the world’s population should have access to improved drinking water, and at least 77 percent should have improved sanitation. While the goal for drinking water is likely to be met, the sanitation goal won’t be. Almost 40 percent of the world’s population remains without improved sanitation and by 2015, this will equal half a billion people.

Research area: Water Supply, Sanitation and Hygiene

Country: Kenya

Evaluation Sample: 220 village clusters in Nairobi, Kenya

Timeline: 2013 - 2017

Intervention: Subsidies; hygiene promotion activities

Researchers: Paul Gertler, University of California at Berkeley; Sebastian Galiani, University of Maryland; Alexandra Orsola-Vidal, Center for Effective Global Action; Aidan Coville, World Bank; Susumu Yoshida, World Bank; Victor Orozco, World Bank; Wendy Ayres, World Bank; Patrick Mwangi, Water and Sanitation Program; Yolande Coombes, Water and Sanitation Program; Andreas Rohde, World Bank

Partners: University of California at BerkeleyUniversity of MarylandGlobal Program on Output Based AidAthi Water Services Board; Nairobi Water and Sewerage Company; Center for Effective Global Action


Governments and development experts are working to develop approaches to boost access to improved water supply and sanitation. Both are critical for better health and development. Improved water supply and sanitation reduces the transmission of disease and is especially important for women and children. It doesn’t just mean healthier lives - it also has an impact on school attendance, health care costs and ultimately, on productivity of people and societies. One barrier to improving sanitation coverage is that poor people are often unwilling to pay for better service. This project will improve our understanding of how to encourage people to pay for better sanitation by evaluating the impact of subsidies and hygiene promotion on people’s willingness to connect their homes to public sewage systems.


The WHO Joint Monitoring Program estimates that 68 percent of Kenyan households do not have access to improved latrines. Many of these people are in informal settlements – also known as slums – which usually aren’t hooked up to the city infrastructure.

This evaluation will support ongoing World Bank work in Kenya through three interlinked projects:(1) the Water and Sanitation Service Improvement Project; (2) Kenya Informal Settlements Improvement Project; and (3) Global Program for Output Based Aid’s support for improving access to Nairobi’s sewerage network. It will do so by studying the determinants of demand for sanitation in Nairobi’s informal settlements to help inform public policy aimed at sustainably increasing improved sanitation coverage in the country.


Intervention and Evaluation Details


In collaboration with the World Bank, the Ministry of Environment, Water and Natural Resources’ Athi Water Services Board (AWSB) together with the Nairobi Water and Sewerage Company (NWSC) will deliver piped water and sewerage services to a number of informal settlements in Nairobi, including Kayole Soweto, Embakasi, River Bank, and Matupeni. Nairobi Water and Sewerage will offer piped water and sewage services to landlords of all compounds in the informal settlements. Each compound has around 6-10 dwellings and they will be hooked up on a first come, first serve basis. Landlords will receive a subsidy to offset initial costs and also credit to help them finance the remaining costs. An awareness campaign directed at landlords will emphasize the benefits of good hygiene and explain the subsidy and credit options. A separate campaign will seek to raise awareness among slum dwellers on the benefits of hand washing and other actions to reduce the transmission of water-borne diseases and keep drinking water uncontaminated. The evaluation will focus on Kayole Soweto, the largest of the informal settlements in the project, and where about 85,000 people live.


The evaluation will be an experimental randomized trial with 220 neighborhood clusters (2,200 compounds) divided among four interventions and a control group: 40 clusters will receive medium subsidies but no hygiene; 40 clusters will receive medium subsidies with the hygiene campaign; another 40 clusters will receive high subsidies for sanitation connection but no hygiene campaign; and the final clusters will receive high subsidies combined with the hygiene campaign. The control group, with 60 clusters, will receive the standard support provided to all households in the community – namely, low subsidies and no hygiene campaign.

Researchers will measure hygiene practices, child health, household welfare, social cohesion, migration, rental charges, and take up rates and willingness to pay for sanitation connections. To understand the sanitation uptake issues better, the researchers also plan to compare households where the landlord resides in the targeted compound (70 percent of cases) to those where the landlord resides elsewhere. Researchers will use administrative data to crosscheck information on water and sanitation services and take-up rates, and to measure cost effectiveness of the interventions.

Policy Impacts

This evaluation can help the Government of Kenya understand how to successfully deliver sanitation more cost-effectively in informal urban settlements. The project has the potential to be scaled up in other informal settlements across Kenya and elsewhere. Given the problems many countries face in promoting take-up of improved sanitation and clean water practices - as many as 2.5 billion people in the developing world have no access to improved sanitation - governments in other countries will also be able to learn from this evaluation.