From Popular Science (Nikita Amir):
Less than 3 percent of Earth is covered in freshwater. And while that percentage has remained pretty constant, population growth has not. Only 1 percent of freshwater is accessible to the 7.7 billion people and counting.
As concerns over water scarcity grow, research published in Nature recently documents how freshwater availability has changed over the years, helping water specialists and managers pinpoint how this essential resource’s flows have been changing. Xander Huggins, a PhD candidate at the University of Victoria and Global Institute for Water Security at the University of Saskatchewan, and his fellow researchers decided to explore what exactly these changes would mean for life here on Earth.
The team examined 1,024 basins across the world to understand how water availability couples with social processes to create vulnerability in communities. The main factor they studied were freshwater stress, which is the amount of H2O that naturally leaves the watershed or basin per year; the higher the stress, the less water there is available for ecosystems and for people’s demands, according to Huggins. Following this, he and his colleagues coupled the findings with data on how freshwater storage in underground aquifers and glaciers, for example, is changing.
Huggins learned that 42 percent of the 478 most stressed basins around the planet are also the ones disproportionately losing storage. These basins, including ones in the American South and Southwest, central Argentina, and throughout the Middle East, are the ones where people and living things are already under pressure. By his team’s calculations, around 2.2 billion people and 27 percent of all global food crop production is located near drying-out freshwater basins.
Identifying vulnerable water sources
After mapping the most high-risk areas, Huggins created a vulnerability analysis by combining the relationship between stress and storage with data on how prepared and economically sufficient a government might be to respond. He hopes that by creating a framework to understand vulnerability and identifying these “hotspot” basins, the water scarcity in these regions can be prioritized by policymakers.
Huggins notes that the metric is simplified enough to use it on a global scale. Out of the 168 “very high” and “high” vulnerability scoring areas, not all faced the same threats. The authors of the paper found that the most vulnerable basins predictably had the worst water resource management, and that basins that spanned countries were even worse off. According to the scale, nations like Algeria, India, and Kazakhstan were found to have high vulnerabilities according to the scale, as well as low levels of water management.
While the US scores highly in terms of social adaptiveness in Huggins’s study, it has multitude freshwater issues that go beyond stress and storage. Equitable access to freshwater sources looks different in communities across the states. According to Jill Ryan, the executive director of Freshwater Future, an advocacy group working on protecting drinking reservoirs in the Great Lakes region, two of the biggest issues are that of water contamination and cost. Illinois and Ohio are the states with the highest levels of lead in their pipes. Rising costs are also making water too expensive for a growing number of families––one of the reasons being new infrastructure to get rid of the lead pipes. This cost is now increasingly being pushed onto the consumers, Ryan says.