The study, which draws on a case study in Mwanza, northern Tanzania, also suggests that short migrations between villages in the developing world are influenced by water availability, while longer distance moves are more strongly influenced by land availability.
The research was carried out in response to the World Bank’s claim that nearly half of the world’s population does not have enough water and that demand is rising and will continue to do so. The Bank also claims water shortages are exacerbated by population growth, are a barrier to development and a source of potential international conflict. The study examines the assumptions about water usage underlying such statements.
The study found that migration is the most important factor in population growth in both villages and towns in Northern Tanzania. Rather than looking at population growth as a cause of water shortage, the researchers examined how water availability influences migration.
The study found that water shortages contribute to poor agriculture performance,
which in turn causes people to migrate away from rural areas. But moving to urban areas often fails to solve people’s water problems: new migrants often settle where water provision is poor; they also lack the social networks of settled inhabitants, who can obtain water from each other.
Even if human populations decrease, problems of resource access will continue to escalate, the study claims, unless both consumption and distribution issues are addressed.
The study covered three broad areas of water use: agricultural, other rural uses and urban use. Questions included: How is water used? How much water is needed? How much water is available? The study also looked at how the assumptions of water engineers in developed countries that emphasise purity, private access, pumping and irrigation lead to unhelpful policies in developing countries.
Key findings include:
- ideal standards of water use are based on water-rich nations and as such may be unrealistic for countries such as Tanzania
- short migrations between villages are influenced by water availability while longer distance moves are more strongly influenced by land availability
- infrastructure rather than water supply is often the problem: piped water networks in urban areas are failing to keep up with population growth
- households that have recently migrated to urban areas have poorer access to water having settled where infrastructure is worst.
- migrants lack the social networks of long term-residents who often sell water to each other
- taken together, both rain-fed and irrigated cultivation can give a better estimate of how self-sufficient a community might be
Policy implications include suggestions that:
- building up urban infrastructure may be more crucial than increasing overall water supplies
- charging for water obtained from standpipes could help recover costs and contribute to better planning and investment in the standpipe network
- selling of water by private households should either be metered, or regulated through a licensing system
- communal facilities for water use, such as bathhouses and laundries, could help alleviate the burden on the poor of increased charges.
- national estimates of water availability for food production should take into account rain-fed agriculture and not just irrigated agriculture