Last month I participated in a very interesting workshop on water and sanitation in rural Bolivia organized by the Ministry of Environment and Water. I learned from the engineers and sociologists there that things are never as simple as economists tend to think. But as the only economist present, I also tried to teach the engineers and sociologists that things are not as simple as they tend to think.
With the combined insights from engineers, sociologists and economists, I have reached the conclusion that 100% coverage is an elusive target for at least five different reasons:
First, the population growth rate in Bolivia is about 1.5% per year, which means that even if we reach 100% coverage by January 2025, by December the same year there will be almost 200,000 additional people who need water and sanitation.
Second, the population is not only constantly growing, but also constantly moving. More than half of all Bolivian municipalities are losing population due to internal migration (see Map 1 below), while a few dozen municipalities are receiving the vast majority of these migrants. The main receiving municipalities are: Santa Cruz de la Sierra (32,000 migrants per year), El Elto (20,000), Cochabamba (11,000), La Guardia (6,000), Warnes (6,000), Oruro (6,000), Sacaba (6,000), and Tarija (5,000) (1). Close to a million Bolivians will have moved from one municipality to another between now and 2025, and most of them will likely come from the disperse rural communities that the government is currently prioritizing for water and sanitation investments. The most extreme example in the map below is the municipality of Chayanta in the northern part of Potosí. In the five years before the 2012 population census, it lost 29% of its population to migration, despite having just reached 94% coverage of water.