Acqua Alta High Tide Flood Forecast in VeniceNovember 1966: Imagine Venice immersed at 100 % by two metres of water!
This time everybody was very afraid, the end of Venice! Venice sank and at the same time the poetry of Lord Byron:
« Ode on Venice” once again surfaced:
Oh Venice! Venice! when thy marble walls
Are level with the waters, there shall be
A cry of nations o'er thy sunken halls,
A loud lament along the sweeping sea!
If I, a northern wanderer, weep for thee »
But truly, Acqua Alta has nothing to do with “the sinking” of Venice, which certainly is true but of less than a millimetre a year.
High Tide Acqua Alta in Venice - Venice flooding forecastAs for the weather, high tides forecast is quite difficult. As a result high tide, Acqua Alta forecast can be at maximum for 4 or 6 days in advance, and it can even change in the last hours.
Alarm Sirens in case of Acqua Alta High Tide in Venice:An initial alert signal will be followed by:
Level 1.10 metres: One long sound.
Level 1.20 metres: Two crescendo sounds.
Level 1.30 metres: Three crescendo sounds.
Level 1.40 metres: Four crescendo sounds.
Listen the High Tide Acqua Alta Alarm Sirens SignalsTo listen these high tide signals, please click on the following links:
Initial alert signal
Signal level 1.10 metres
Signal level 1.20 metres
Signal level 1.30 metres
Signal level 1.40 metres
Warning Codes in case of High Tide (Acqua Alta) in Venice
|Tide between 0.8 metres and 1.10 metres||High Level||Warning Code Yellow|
|Tide between 1.10 metres and 1.40 metres||Very High Level||Warning Code Orange|
|Tide level over 1.40 metres||Exceptional Level||Warning Code Red|
Venice under water: Town Surface percentagePercentage of Venice that will be under water for different tide levels.
Warning: "Under water" begins at one centimetre of water covering the ground, meaning that in the following table, some parts of Venice can be under 10 centimetres of water while for others it will just be a paddle like after the rain!
Interactive Venice map with levels. Click on the + arrow on the map to enlarge and know the levels for each street (in centimetres)
Percentage of the whole Venice Surface under water depending on the tide level:
1 metre: 3,56 % of Venice is under water
1.10 metres: 11,74 % of Venice is under water
1.20 metres: 35,18 % of Venice is under water
1.30 metres: 68,75 % of Venice is under water
1.40 metres: 90,19 % of Venice is under water
1.50 metres: 96,33 % of Venice is under water
1.60 metres: 99,27 % of Venice is under water
1.70 metres: 99,74 % of Venice is under water
1.80 metres: 99,86 % of Venice is under water
Certainly, over last century, Venice sank about 10 centimetres, due to industrial groundwater extraction but largely stopped when artesian wells on the mainland were capped in the 1960s.
Acqua Alta, what is it?Then it is what? Acqua Alta occurs when certain events coincide; the high tide forms an alliance with low pressures and that their windy friend, Sirocco, participates with our friend the Moon.
These elements together trigger the across-the-board flood of waters of the lagoon in Venice.
When Acqua Alta plays the MusicHistory is true and arrived at Igor Stravinsky the Acqua Alta had been then so high as the compositor could no longer return to his hotel.
The concierge of aforementioned hotel Bauer, took Igor Stravinsky in his arms and carried him indoors.
It was after this Acqua Alta that Igor Stravinsky writes “The Flood”!
Our Advises Living well with Acqua AltaThe biggest problems Acqua Alta poses, at most some centimetres of water in calli (streets) which gives them a glistening aspect, is getting the camera quickly!
Besides, you will be warned in case of serious Acqua Alta. Sirens (which still date to the last world war), will shout a warning signal. If you are surprised in the city without Wellington boots, the dealers will be delighted to give you plastic bags for makeshift boots to make waiting better!
The period at risk is from September 15th till April 15th every year.
If you think to visit at this time of the year, it is best to be prepared with a pair of Wellington boots and enjoy the pleasure, as the children, of walking in the puddles!
MO.S.E planIt is a big “Pharaonic” plan of the installation of seawalls to try to check the phenomena of Acqua Alta by installing in the entries of the lagoon (in the channels of Lido, Malamocco and Chiogga) 78 floating seawalls on about 1600 metres and divided in four chunks with huge hatches that can close up or open according to the whims of the tide.
The estimated cost is of 5,5 thousand million euro more about 35 million euro of expense of annual maintenance. It should be done by the end of year 2020.
Useful Internet sitesCity of Venice flood planes in Venice - Acqua Alta Levels
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