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Venice is, in essence, a prodigy of Inverted engineering: It stands on millions of stuck piles On the contrary in the Lagunar mud, creating what has been described as a submerged forest down. These trunks, made with trees, have supported for centuries the burden of stone palaces and imposing bells without resorting to steel or concrete. The physical principle that supports this system is not based on the brute force of the materials, but on the friction of compressed humid soil that, together with wood and water, constitutes a resistant tripartite structure. However, that skeleton It has a serious problem. The abyss. The mythical city lives a cruel paradox: it is not only a city that floats, but one that It sinks. In the last century, the Venetian floor has descended about 25 centimeterswhile the sea level has risen about 30. In other words: it is a lethal combination that has triggered increasingly frequent and severe floods. While its decay adds some tourist magnetism (visiting it before it disappears), for Venetians it is a persistent threat that compromises your future. The city sinks two millimeters a year due to natural subsidence, while the waters increase some Five millimeters annually due to climate change. An unpublished plan. Before this existential threat, the engineer Pietro TeatiniAssociate Professor of Hydrology and Hydraulic Engineering at the University of Padua, proposes a solution as bold as controversial: physically raise the city Injecting water into aquifers deep between 600 and 1,000 meters under the lagoon. The idea is born from the observation of gas reservoirs in the Valle del Powhere when filling during the summer, the terrain rises, and goes down when they are emptied in winter. According to Teatini, through this technique, Venice It could rise 30 centimeters In a stable and homogeneous way, enough to grant a break of about five decades, in which the authorities could plan a definitive solution. Drill and drill. The project would consist of pour a dozen wells Distributed in a circle of 10 kilometers around the city, all located inside the lagoon. Water to be injected would be saline, taking advantage of the abundant local resource and without risk of contaminating fresh water aquifers. To ensure stability, it would be injected at low pressure and slowlyavoiding fractures in the underground rock. The choice of a wide circumference guarantees a uniform elevation that would not damage historical structures. Chioggiaat the southern end of the lagoon, it would be outside the radius of action. The system that was not enough. The search for solutions also exposes a failure. Currently, Venice’s main defense against high tides is The Mose system (Sperimentale Electromeccanico Module), a series of mobile gates that rise from the seabed to isolate the Adriatic Sea lagoon. Although it began to plan in the 80s and was tested for the first time in 2020, its cost has exceeded seven billion of euros and is not yet officially operational. Originally conceived to activate five times a year, since 2020 it has already been used about 100 timesreflex of the problem. Every time it is activated, interrupts maritime traffiche harms the port (the second most active in Italy) and alters the ecological balance of the lagoon by preventing the natural flow of water. Mosetherefore, it does not solve the problem, and Teatini proposes its project as a temporary complement by extending the combined functionality of both systems during those 50 yearsmargin that could be used to develop a definitive structural solution. Venice towards the end of the seventeenth century Underground technology Theatini’s plan It is not frackingnor is it based on extreme pressures. It is rather a controlled process that has been used in oil engineering to stabilize platforms. The idea is that water gradually penetrates the deep sandy substrate, expanding and pushing the ground up without causing fissures. A maximum elevation of 30 centimeters is the technical limit that can be achieved without compromise stability. The pumping rhythm would gradually reduce to avoid overloading aquifers, and the incorporation of additives that maintain the expansion achieved even if the pumping is interrupted is studied. To prove the viability, a pilot project is proposed in another part of the lagoon, less critical, with an estimated cost of Between 30 and 40 million euros. The complete implementation would be three times cheaper than the Mose. Plus: The approach is more realistic than other ideas raised in the past, such as shallow cement injections that were used limited to islands such as Poveglia in the 70s. Race against time. No doubt, some experts are skeptical. David Dobson, professor of materials at University College London, acknowledges that the idea generates “skeptical optimism”. It warns that the aquifers already collapsed (as happened in Marghera when water was extracted in the 60s) may not recover its original volume. In addition, injecting water is more difficult than gas, as it flows more slowly and requires greater pressure. However, he argues that, if a successful essay is carried out and the process control is demonstrated, the proposal It could be truthful. In any case, he points out that the root of the problem remains Global warmingand as long as it is not addressed, any solution will necessarily be temporary. Symbol and priority. Teatini has been studying the phenomenon of the Subsidy in Venice. His Thesis with doctorate He already addressed this problem, and was his former professor, Giuseppe Gambolati, who first proposed those deep injections as a solution. Today, in the face of institutional inertia, he insists that his proposal is the only technically developed that can begin to be tested immediately. In addition, with the creation in March 2025 of the New authority per the lagoona state entity that will be in charge of evaluating interventions in the lagoon and planning the future, a window of opportunity opens. Although every plan will have high costs, Teatini argues that it is a Reasonable investment and even possible with citizen financing. The big doubt. In addition, there is the … Read more