It is estimated that even today some 2.2 billion people lack access to safe drinking water, while 3.5 billion live without safe sanitation. Impressive numbers that are worth remembering, even in a country where drinking water may seem like a foregone commodity, whose certainty and safety are called into question only on rare and timely occasions: when it is lacking due to some fault, when its quality is compromised by external agents, or if it gets out of hand in extreme weather events.
The observation may seem trivial, but water is life. Early civilizations thrived along rivers. Humans have invented increasingly complex systems to control it in all its forms and derive nourishment, energy, and communication routes from it. Finally, it is no coincidence that, looking to the sky, we look for worlds in which we find traces of it. In its reflection, in short, humankind is mirrored.
For World Water Day, celebrated worldwide on March 22, let's try to understand what it can tell us through the work of a researcher and a researcher from the Department of Environment Construction and Design, metaphorically immersed every day in this fundamental element.
Rodolfo Perego is a researcher in the Hydrogeology Sector of the Institute of Earth Sciences. “We are in charge of monitoring, on behalf of the Canton and within research projects, groundwater to understand its dynamics and to improve its management.”
Research that starts from the basic assumption that water is not a given commodity, even in a country where Europe's major rivers are born, like Switzerland. Water resource management needs to be increasingly refined to ensure adequate supply and premonition works to cope with periods of stress, such as those experienced in the recent past between floods and droughts.
“In valley floor aquifers,” Rodolfo Perego continues, ”the minimum information we need for monitoring is the piezometric level, which is the groundwater elevation expressed in meters above sea level. If we have several points distributed over the territory, we can correlate this information to understand the direction in which the water is flowing and estimate an outflow velocity. The trend of levels over time also gives us information about the discharge/recharge time of the aquifer and the correlation of groundwater with precipitation.”
“If we analyze data on temperature and electrical conductivity-proportional to how many dissolved ions are in the water: the higher it is, the more dissolved salts and minerals there are-we have information on any influences on groundwater from streams such as rivers; or information on what types of rocks the water has passed through. In the case of springs, which are still groundwater, but in rocky aquifers, flow, temperature, and electrical conductivity data are also very important because they allow us to determine their degree of vulnerability and thus identify what approaches to use in defining protection zones. In recent years, two projects in particular have been very useful in learning how to use signal analysis techniques to quantify the relationship between river and aquifer: the projects 'Characterization of the Interaction between the Vedeggio River and Groundwater' and 'Evaluation of the Effect of Minimum Runoff Remediation on Groundwater'.”
From the waters that we do not see, but heedlessly continue to flow under our feet, we move on to those that we occasionally do not want to see, as they are not in their most crystalline form, but just as fundamental and full of valuable information.
“As far as microbiology is concerned, water is an interesting environment,” began Federica Mauri, researcher and head of the Hygiene and Environment Sector of the Institute of Microbiology. Surface waters such as those of our rivers, the deeper layers of the lake, but also the wastewater that reaches the sewage treatment plants, are populated by invisible organisms (bacteria, fungi and viruses) different for each environment. Most of them are critical to the maintenance of the ecosystem because they are involved in biogeochemical processes that are fundamental to life. Therefore, it is important to study their function and biodiversity. Others, however, can be pathogenic to humans and animals so it is essential to monitor their spread.”
From reading and analyzing this information we can also draw conclusions about our footprint. “Water monitoring serves to assess the impact-usually negative-of human activities on the microbial populations present and can provide a lot of valuable information for our health as well. For example, the identification of pathogenic microorganisms in wastewater, but also in river and lake water, can tell us how widespread they are in the population. The Hygiene and Environment Sector is leading two projects in this area. The first, concluded in 2023, monitored the presence of SARS-CoV-2 in the wastewater of some sewage treatment plants in the Canton of Ticino; the other, ongoing since 2016, involves monitoring the presence of antibiotic-resistant bacteria in some local waterways and in Lake Lugano.”
The words of Rodolfo Perego and Federica Mauri give us an idea of how wide and deep research on water can be, which also touches other SUPSI departments in the most diverse ways. Proving that water, in all its forms and dimensions, is an element for which there is and always will be a thirst for knowledge.