Groundwater: the importance of its management for sustainability
The tiny fraction of fresh water enjoyed by all living things on this planet, which is not held in ice caps and glaciers, accounts for only a very small part of the total volume of water on earth. However, this essential resource, which is stored primarily as groundwater, is distributed quite unevenly around the world.
Physical and economic constraints make it impractical in most cases to move large volumes of water from areas in surplus to those in need.
Next, we will learn more about all the circumstances surrounding groundwater.
Regional scarcity has become a serious and growing problem, as rapidly growing populations rely on county water supplies, which are being depleted, degraded and partitioned. between more and more users. Alarmingly, aquifers, which are crucial to the food security of hundreds of millions of people, are being unsustainably exploited in some of the world’s major agricultural regions such as China, India and the United States.
Thus, global demands for fresh water have been growing at roughly twice the rate of world population over the last century.. Despite this, this volume of thawed fresh water is still more than enough to satisfy all human needs.
What is the status of drinking water?
The intensive use of groundwater is a relatively recent phenomenon which began in industrialized countries in the 1950s and reached much of the developing world between 1970 and 1990. The development of cheaper drilling and pumping techniques has helped make it an increasingly popular alternative to surface water to meet growing global demand. Water from aquifers is generally of higher quality than surface water and is much less subject to seasonal and interannual variations, which makes it a more reliable source of supply.
Many cities have turned to groundwater for drinking water supply and domestic because surface sources have been contaminated. Nearly half of the world’s population uses groundwater for drinking, and an increasing proportion of farmers rely on groundwater to irrigate their fields.
In North Africa and the Arabian Peninsula, huge reserves of non-renewable groundwater have enabled large irrigation projects in the middle of the Sahara and Arabian deserts. In the Punjab of India and Pakistan, the heart of the “green revolution” of the 1970s, groundwater, along with new crop varieties and improved inputs, have enabled a large increase in agricultural productivity .
Difficult conservation of groundwater.
Despite the many successes of groundwater development around the world, there are also very serious problems. In general, these incidents they are the result of reduced groundwater volume , as its withdrawal is greater than what is replenished by rainfall and surface water flows.
Even when abstraction does not exceed replenishment, it can alter the complex dynamics of the aquifer system, slowing the flow of springs and streams, and degrading water quality. Also, undermining the sustainability of ongoing human uses has been linked to a reduced ability to support ecosystem functions. This unsustainable overexploitation can be avoided with proper management that incorporates resource understanding and realistic use scenarios.
Over-exploitation of groundwater in many places has already caused local or regional water tables to decline, making continued water extraction more difficult and costly., which is already causing problems in many regions of Latin America. This finding is supported by satellite data showing changes in total water storage as inferred from gravity measurements, which estimated a lowering of the water table.
Additionally, several recent studies have shown that several aquifers in large geographical areas near the coast have begun to fill with salt water of marine origin, which will make it impossible to continue practicing agriculture in some of these regions. .
Since the 1950s, both population and irrigated areas have grown so much in Latin America that there has been no choice but to make ever-increasing use of groundwater. This unsustainable rate of extraction is a serious threat to future agricultural productivity and domestic water supplies.
How will you address this issue at the Ninth World Water Forum?
World Water Day One of its main objectives is to emphasize the role of groundwater. From March 21 (until 26), coinciding with the Ninth World Water Forum (Dakar, Senegal), numerous events focused on this and other highly relevant issues, such as sanitation, innovation or climate change, will take place .
The objective is to promote better management of underground resources, taking into account that they constitute 98% of the fresh water available on the planet. Some aquifers are so large that they could hold more than 30 times the water capacity of Spain. In fact, more than a quarter of the world’s population depends exclusively on these sources to meet their daily needs.
According to the UN, the threat to its sustainability is serious. For this reason, in the next World Water Forum, aquifers will have a prominent place, framed within the Sustainable Development Goals (SDG).
In short, the extreme pressure to which man subjects groundwater reserves of the planet could have terrible consequences in the medium term. It is, therefore, one of the most urgent areas to be dealt with by the water agenda of many countries, and will be one of the highlights of the Ninth World Water Forum.