Chart: Are we getting better at using water?

It’s often said that in the future, wars will be fought over water. But globally, the world may be getting better at saving those precious drops. For a paper in Hydrological Sciences Journal,  researchers from the Joint Global Change Research Institute (JGCRI) and the  University of Alberta have developed three models for global water use over the next century:

Business-As-Usual Scenario (BAU): assumes the continuation of current trends in population, economy, technology, and human behavior to year 2100.

Low-Tech Scenario: assumes a world of higher population and GDP growth, but lower per-capita income growth than the BAU scenario; with low income growth, less money is invested in technological advancements.

High-Tech Scenario: unlike the low-tech scenario, this assumes a world of lower population and GDP growth but higher per-capita income growth than the BAU scenario; with high income growth, greater investments are likely to promote technological advancements.

The models are charted below:

In the BAU scenario, water use continues to grow but at a slower rate than in previous years. Under the high-tech scenario, use is actually lower in 2100 than it was in 2005. The researchers note that “Such a decline in water use has been observed historically for some developed countries, where per-capita water use declined despite rising populations, likely due to technological improvements and conservation measures.” 

Of course, this is a worldwide picture. It doesn’t address the inequalities in water access between developed and developing countries that are predicted by many to grow in the next cenutry. And even under the high-tech scenario, countries like Yemen are still facing an acute water crisis in just the next decade.