New Groundwater Map Drawn By Hydrologists – Are We Using Up Freshwater Faster Than It Can Get Replenished?

A new groundwater map drawn using only modern-day data points has offered a first-ever real-life indicator of our most precious natural resource.

New research from the University of Victoria has offered a map of underground water reservoirs across the globe. The first-of-its-kind map showing the world’s hidden groundwater sites, and the spread was published on Monday. Such a map will offer a realistic estimate of how much groundwater the earth has and, more importantly, how fast it is being used up. Overuse of water is a common phenomenon, and this groundwater map will hopefully serve as a strong reminder that the natural resource runs the risk of depleting too quickly if its usage isn’t managed correctly.

Using data from close to a million watersheds, as well as 40,000 groundwater models developed through computer simulation, the study has attempted to accurately estimate how much groundwater lies a few meters beneath our feet, reported KelowNow. There have been increasing concerns that the groundwater is being used up at an alarming rate, and they might soon run dry. Interestingly, water stored in reservoirs and rock fractures that run deep underground may not be depleting at the rates as currently feared.

In total, the Earth has more than 5.42 cubic miles (22.6 cubic km) of water buried beneath. For simplicity of perception, the earth holds so much groundwater in its belly that if it were to come to the surface all at once, quite a few regions would go under 590 feet (179 meters) of liquid, reported the Daily Mail. The quantity of water easily surpasses all other water sources except the great oceans. A small percentage of this vast reservoir makes it to the surface. While it is a good thing for earth’s inhabitants that only a very small percentage of water comes up, what’s concerning is that an even smaller percentage of that water is actually potable or safe for human consumption.

Despite the humongous untapped reserves, it is the usable groundwater that can be termed as “renewable.” An international team of researchers estimated that less than 6 percent and perhaps as little as 1 percent of water found close to the Earth’s surface is renewable in a human lifetime, reported Trust. The water is in the upper two kilometers of the Earth’s landmass.

Speaking about the delicate balance that needs to be maintained to ensure adequate supply continues, the lead author of the study, Tom Gleeson of Canada’s University of Victoria, said, “This has never been known before. We already know that water levels in lots of aquifers are dropping. We’re using our groundwater resources too fast – faster than they’re being renewed.”

Climate change is one of the factors that are responsible for rising demand for water. This new groundwater map offers never before available information to those entrusted with managing water resources and those who enact policies for water conservation. Experts from fields of hydrology, atmospheric science, geochemistry, and oceanography are now better equipped to understand groundwater resources and, more importantly, its intelligent management.

The research team was further able to demarcate young and old groundwater. These two types of water interact very differently with the rest of the above-the-surface water resources. Old groundwater may have remained trapped in deep pockets for hundreds, thousands, or even millions of years. This water isn’t fit for human consumption but can be used for agriculture and industries. Often brackish, old groundwater may be even more saline that seawater. In some cases, the briny water is so ancient and stagnant it can be considered as a non-renewable resource, shared Gleeson.

It is the young groundwater reserves that are important to humans and other biology on the planet. Unfortunately, being closer to the surface, it is more susceptible to climate change and contamination. Since the new groundwater maps reveal where such groundwater lies, they can be protected.

[Photo by Ken James/Bloomberg/Getty Images]