Researchers studying a water supply programme for Ethiopian villages found that it had many benefits, but one unpredicted result was an increase in the birth rate. The demands on the scarce resources available to the villages therefore increased. The study, conducted by researchers at the University of Bristol and University College London, UK, is published in the latest issue of PLoS Medicine.

Improving access to water is one of the most important goals of development programmes in rural Africa. In the part of Ethiopia where this research was done, many women spend three hours every day walking to fetch water, which they carry home in clay pots. In those villages where tapped water has been supplied, the time spent getting water has gone down to about 15 minutes. Programmes that achieve such a result are generally hailed as a success but it is unusual for their wider impact on the population to be studied.

The research involved nearly 2000 households in both villages with and without access to improved water supply. The death rate of children in the villages where tapped water had been introduced was found to be much lower than it was in the other villages. However, the birth rate was much higher in the villages with tapped water than it was in the other villages.

It has been argued that when development improves living conditions and health, there will be a reduction in birth rate. This has happened in many countries but, in rural Africa, birth rates remain high and the population is growing rapidly. Ethiopia is an example; the rising population and the slow growth in the economy have led to repeated humanitarian crises.

A further finding in the study was surprising: the nutritional status of children fell in the villages which had taps, even though their risk of dying was lower.

Gibson and Mace say their study is the first to show a link between the introduction of a ’technological intervention’ and an increase in birth rate. They suggest that development programmes should be ’multisectoral’, instead of focussing on just one issue (in this case, water supply). In particular, programmes should routinely include improved access to contraceptives.