Why is this Italian town slowly sinking into the sea?

Venice is celebrated globally for its winding canals and historic architecture. However, this iconic Italian destination is facing a severe environmental crisis. The town is gradually sinking into the Adriatic Sea. According to reports from the European Geosciences Union, the ground level is dropping by roughly one to two millimetres every year. Here is a factual look at why this famous water-bound settlement is slowly going underwater and the engineering techniques being used to save it.

The shifting tectonic plates and wooden foundations

The primary cause of the sinking, known scientifically as subsidence, is natural. Venice is built on 116 muddy islands, supported by millions of petrified wooden piles driven into the clay. However, the town sits on the Adriatic tectonic plate, which is slowly shifting and subducting beneath the Apennine Mountains. This geological movement pulls the entire lagoon floor downwards. According to a report by the Scripps Institution of Oceanography, this natural tectonic settling causes the ground to sink continuously, making the wooden foundations increasingly vulnerable.

Historical groundwater extraction

Human industrial activity significantly accelerated the sinking process during the 20th century. In the 1950s and 1960s, local factories pumped massive amounts of fresh groundwater from the deep artesian aquifers beneath the lagoon. This extreme water extraction caused the soft clay and sediment foundations to dry out, compact, and permanently collapse. Although the Italian government officially banned industrial groundwater pumping in the 1970s, the structural damage was already done. The town sank by an estimated 15 centimetres during this short period alone.

Rising sea levels and the Rs 630 billion MOSE project

While the ground continues to sink, the Adriatic Sea is simultaneously rising due to global climate change. This dangerous combination leads to severe tidal flooding events locally known as 'Acqua Alta'. To combat this dual threat, Italy developed the MOSE project. This advanced engineering system features 78 mobile gates lying on the seabed at the three main lagoon inlets. During dangerously high tides, compressed air raises these gates to block the sea water. According to official Italian government data, the massive flood defence project cost approximately 7 billion euros (roughly Rs 630 billion) to complete.

While the MOSE barriers currently protect Venice from extreme flooding, the geological sinking remains an ongoing challenge. Travellers visiting the region should strictly follow local environmental guidelines and consider travelling during the off-season to reduce the immense physical strain on the fragile town infrastructure.