Water shortages moreover, are exacerbated by population growth and seen as a barrier to development and as a source of potential international conflict. The study examines the assumptions about water usage underlying such statements. 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 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.
Migrants lack the social networks of long term-residents who often sell water to each other.