Last November 19th we celebrated World Sanitation Day, a day aimed to raise awareness about taking measures to address the global crisis and achieve Sustainable Development Goal 6: sanitation and water for all in 2030.
This year’s theme has been “Making visible the invisible resource”, focused on the impact of the sanitation world crisis in groundwater, since an inadequate sanitation system can run the risk of spreading wastewater into rivers, lakes and soils, thus contaminating groundwater resources.
Today, we get to know Jaime Gómez Hernández, Professor of Hydraulic Engineering at the School of Civil Engineering, Canals and Ports of the Polytechnic University of Valencia and head of the Hydrology research group of the Institute of Water and Environmental Engineering of the Polytechnic University of Valencia.
Although groundwater can be classified as an invisible water resource, groundwater has been known since time immemorial, and its contribution to the water cycle can be seen in the base flows of rivers, in the presence of wetlands or in the fountains and springs.The great extension of the aquifers and the slow movement within them, make them especially fragile elements; on the one hand, because contamination can access the aquifer in innumerable ways (directly and indirectly) and, on the other hand, because Detection of said contamination can occur long after it has occurred, when it may be too late to be able to recover the quality of the aquifer in an affordable time and cost.
The biggest challenge we face is to become aware that prevention is better than cure and that all possible measures must be taken to prevent water pollution from occurring. For example, as has been done in the last revision of the nitrates decree, where the increase in the size of protected areas has been increased in order to minimize the risk of contamination of both surface and groundwater.
The sustainable management of groundwater requires a long-term balance between the amount withdrawn from aquifers and their recharge.
Mediterranean aquifers are generally found in arid or semi-arid areas and, therefore, are an essential resource for social and economic development. In many many cases, it is these that provide water security.
We could say that the most common problems in aquifers are overexploitation, marine intrusion and nitrate contamination. Some of these problems are also manifested in those of European aquifers in wetter areas, such as nutrient pollution.
Today, the need for interaction between all the actors involved is becoming more and more evident. We have seen this in the InTheMED project, where users and companies that exploit aquifers appreciate holding meetings with the participation of all of them to better understand the problems faced by aquifers and reach agreed solutions between users and administration.
The techniques used to detect groundwater are many, but we can classify them into two main ones: direct, which measures the properties of the aquifer or its state in situ, and indirect, such as geophysical techniques that measure other parameters that are later related to those of interest.
The characterization of an aquifer is essential to build a model of it (first conceptual, then numerical) that allows us to understand the functioning of the system and to be able to make predictions about its evolution.
All stakeholders are aware of the importance and impact that climate change is going to have on water resources. Acting to alleviate this impact is a task that can only be addressed jointly.
In my opinion, one of the key results of the project has been to realize that the planning and governance of groundwater cannot be based exclusively on technical studies, but that the socio-economic component is as important as the technical one, and only including this component in the analysis can a sustainable management of aquifers be achieved.
Spain has been a benchmark in the management of water resources for many years. This additional investment will only serve to strengthen that leadership.