The incredible images of a dry Venice, why did the canals lose their water?

We are used to associating Venice in winter with images of  water flooding the plazas and squares, a common problem in the city during that season. But the photos that are going around the world in February 2023, like this one, are very different to what we are used to.

The water shortage is so evident that its famous canals are half-empty, almost reduced to muddy streets. The foundations of the oldest palaces are visible even in the most emblematic ones, such as the Grand Canal.

Dry canals respond to a particular phenomenon that usually affects the city in January and February, with 69% of the cases occurring in these months.

The phenomenon, defined as "exceptional low tide," is not so unusual for Venice.

An "exceptionally low tide" is defined as when the water levels are 20 inches below the neutral level or "zero tides." This year's shallow wave is not a record one.

In the photo: the low tide of 2022.

Venice has recorded 160 exceptional low-tide events, with water levels 20 inches below, since 1872.  The last exceptional one was on February 7, 1989, with a minimum of -36 inches.

The 2023 data, albeit worrying and 'exceptional,' does not represent a record for the Venetian capital. According to the Tide Office of the Municipality of Venice, the lowest index recorded dates back to 1934, when it reached 48 inches below the zero tide mark.

The municipal tide forecast center explains the exceptional nature of the phenomenon is not the shallow measurements reached in the lagoon (27 inches lower).

More than the water levels, what worried authorities and citizens about the event was how long it lasted.

According to data from the tide office of the Municipality of Venice, in 2005, the low tide lasted 48 hours, then in 2002 and 2007, it lasted 28 hours, and in 2004, it reached 27 hours. In 2023, these numbers have increased considerably.

In the photo: the shallow tide of 2022

And in the last decade, this phenomenon has been less frequent: in 2021, for example, there were only 2 hours of exceptional low tide, while in 2022, there were only 9 hours with the water level 20 inches below the tide mark.

The consequences of the excessive duration of this event, especially in terms of navigability, are severe. The canals are not just a tourist attraction. They are the communication routes of the city, and the dry paths take a toll on the daily life of Venetians.

A striking example is water ambulances, forced to stop in canals without water and unable to reach their patients or food suppliers that usually move through the water. They are now forced to seek alternatives.

Alvise Papa, head of the Venice tide office, expressed his surprise to the Ansa agency: "The low tide is registering an important value. The duration of the event with the water level 20 inches below. It has been at least 15 years since we had such a long low tide."

The phenomenon, the expert continued, is not a direct consequence of the drought that affected Northern Italy in the summer of 2022 and continues to affect this area of the country in 2023.

Still, the shallow tide is related to the drought. Both are a consequence of an anticyclonic event affecting a large area of Europe this winter.

An anticyclone in meteorology is a high-pressure atmospheric area in which the air acquires greater density and increases its temperature, becoming drier: in simple terms, it becomes a barrier for rain and storms.

Drought and exceptional low tides are two sides of the same coin and two distinct effects of the same phenomenon, of which, unfortunately, Venice is an illustrious victim.