The Italian city of Venice is seeing its worst flooding in decades, prompting Italy's Prime Minister Giuseppe Conte to declare a state of emergency.

High tides of 140 centimeters (55 inches) or more are known as "acqua alta" in Italian, and generally take place in winter, according to Venice's municipality website. The exceptionally high tide Venice is experiencing now peaked on Tuesday at 187 centimeters (74 inches), according to a statement Wednesday morning from Venice's government.

It is the worst flooding in Venice since 1966, when the city was hit by tides of up to 194 centimeters (76 inches), according to government statistics.

Some 45% of the city was flooded, Venice's Tide Forecasting and Reporting Center of Civil Protection said Tuesday.

Pumps spout water from a flooded restaurant on November 17.
Pumps spout water from a flooded restaurant on November 17.
Awakening/Getty Images
A man sits on a stepladder inside a shop as a woman walks down a flooded street.
A man sits on a stepladder inside a shop as a woman walks down a flooded street.
Filippo Monteforte/AFP/Getty Images
A flooded St. Mark's Square is seen on Friday, November 15, in Venice, Italy.
A flooded St. Mark's Square is seen on Friday, November 15, in Venice, Italy.
Luca Bruno/AP
People traverse a provisional footpath built over flood waters on Friday, November 15, in Venice, Italy.
People traverse a provisional footpath built over flood waters on Friday, November 15, in Venice, Italy.
Marco Valle
Guests inspect high tidal waters inside a Venice hotel, on Friday, November 15.
Guests inspect high tidal waters inside a Venice hotel, on Friday, November 15.
Silvia Longhi
Volunteers treat damaged music sheets from the historical archive of the Conservatorio Benedetto Marcello, on Friday, November 15. Important music sheets have been damaged by unexpected flooding throughout the city of Venice.
Volunteers treat damaged music sheets from the historical archive of the Conservatorio Benedetto Marcello, on Friday, November 15. Important music sheets have been damaged by unexpected flooding throughout the city of Venice.
Silvia Longhi
A man carries luggage Friday as he wades through the flood.
A man carries luggage Friday as he wades through the flood.
Luca Bruno/AP
Banksy's migrant child mural is seen <a href="https://edition.cnn.com/style/article/banksy-work-venice-floods-scli-intl/index.html" target="_blank">partially submerged</a> on Friday.
Banksy's migrant child mural is seen partially submerged on Friday.
Luca Bruno/AP
A woman checks the state of books from renowned bookstore "Acqua Alta" (High Water) on Friday after flooding in Venice.
A woman checks the state of books from renowned bookstore "Acqua Alta" (High Water) on Friday after flooding in Venice.
Luca Bruno/AP
A woman with a selfie stick makes her through a flooded St. Mark's Square.
A woman with a selfie stick makes her through a flooded St. Mark's Square.
Luca Bruno/AP
People wade Friday through a flooded Venice alley.
People wade Friday through a flooded Venice alley.
Luca Bruno/AP
People wearing waterproof shoe covers walk through floodwater on Thursday, November 14, at St. Mark's Square in Venice, Italy.
People wearing waterproof shoe covers walk through floodwater on Thursday, November 14, at St. Mark's Square in Venice, Italy.
Filippo Monteforte/AFP via Getty Images
In a photo taken on Tuesday, November 12, flooding is seen inside Ferro Fini Palace in Venice. Democratic Party councilor Andrea Zanoni said on Facebook that the <a href="https://edition.cnn.com/2019/11/14/europe/veneto-council-climate-change-floods-trnd-intl-scli/index.html" target="_blank">Palace's council chamber started to take in water</a> around 10 p.m. local time on Tuesday, as councilors were debating the 2020 regional budget.
In a photo taken on Tuesday, November 12, flooding is seen inside Ferro Fini Palace in Venice. Democratic Party councilor Andrea Zanoni said on Facebook that the Palace's council chamber started to take in water around 10 p.m. local time on Tuesday, as councilors were debating the 2020 regional budget.
Andrea Zanoni
A group of Gondoliers are seen on a pier in Venice, after the city suffered its highest tide in 50 years.
A group of Gondoliers are seen on a pier in Venice, after the city suffered its highest tide in 50 years.
Filippo Monteforte/AFP via Getty Images
Italian Prime Minister Giuseppe Conte surveys flood damage in Venice on November 14.
Italian Prime Minister Giuseppe Conte surveys flood damage in Venice on November 14.
Handout/Filippo Attili/Palazzo Chigi/Anadolu Agency via Getty Images
Members of the municipal police stand in water by St. Mark's Basilica on November 14.
Members of the municipal police stand in water by St. Mark's Basilica on November 14.
Filippo Monteforte/AFP via Getty Images
Head of the Forza Italia party and former Italian Prime Minister Silvio Berlusconi, second from right, assesses the flood damage on November 14.
Head of the Forza Italia party and former Italian Prime Minister Silvio Berlusconi, second from right, assesses the flood damage on November 14.
Filippo Monteforte/AFP via Getty Images
A shopkeeper throws out water from his flooded store on Wednesday, November 13.
A shopkeeper throws out water from his flooded store on Wednesday, November 13.
Simone Padovani/Awakening/Getty Images
A woman sits in a chair in a flooded St. Mark's Square on November 13.
A woman sits in a chair in a flooded St. Mark's Square on November 13.
Luca Bruno/AP
People walk past a stranded water taxi after it was washed from its mooring by the high tide.
People walk past a stranded water taxi after it was washed from its mooring by the high tide.
Marco Bertorello/AFP via Getty Images
A woman crosses a flooded St. Mark's Square on November 13, after an exceptionally high tide inundated the area overnight.
A woman crosses a flooded St. Mark's Square on November 13, after an exceptionally high tide inundated the area overnight.
Marco Bertorello/AFP via Getty Images
A woman walks her dog through a flooded street on November 13.
A woman walks her dog through a flooded street on November 13.
Marco Bertorello/AFP via Getty Images
A general view shows a man crossing the flooded St. Mark's Square on November 13.
A general view shows a man crossing the flooded St. Mark's Square on November 13.
Marco Bertorello/AFP via Getty Images
Police officers patrol a flooded St. Mark's Square during the high tide on November 12.
Police officers patrol a flooded St. Mark's Square during the high tide on November 12.
Marco Bertorello/AFP via Getty Images
A man stands inside a restaurant barricaded from the flooding on November 12.
A man stands inside a restaurant barricaded from the flooding on November 12.
Marco Bertorello/AFP via Getty Images
An employee of the Gritti Palace helps a customer navigate a flooded entrance on November 12.
An employee of the Gritti Palace helps a customer navigate a flooded entrance on November 12.
Marco Bertorello/AFP via Getty Images
A woman stands on a barrier during an exceptional "alta acqua" high tide on November 12.
A woman stands on a barrier during an exceptional "alta acqua" high tide on November 12.
Marco Bertorello/AFP via Getty Images
People traverse a footpath built over the flood waters.
People traverse a footpath built over the flood waters.
Luca Bruno/AP
The entrance to St. Mark's Basilica is flooded on November 12.
The entrance to St. Mark's Basilica is flooded on November 12.
Luca Bruno/AP
People walk through flood waters in St. Mark's Square on Tuesday.
People walk through flood waters in St. Mark's Square on Tuesday.
Luca Bruno/AP
The high tide is seen near the Rialto Bridge in Venice.
The high tide is seen near the Rialto Bridge in Venice.
Luca Bruno/AP
A person photographs a flooded St. Mark's Square on November 12.
A person photographs a flooded St. Mark's Square on November 12.
Luca Bruno/AP