zh

Venezia ObServer, Ship Traffic Impact
on the Historical Port of Venice

italiano english venessian

Photos and seismic observation by Etele Pechy
Text by Umberto Sartory


We cannot, as of now, dispose of data enough to completely comprehend the complexity of chemical, physical and social inferences of the ship traffic in the urban pattern of Venice.

By our observations, we anyway dispose of enough evidences to locate some factors, and over all to point out the tragic menace for our Historical Centre.





Ship fumes release amounts of sulphuric and nitric pollutants, enough to shortly crumble all of the stones of the town in chalky mud.


Pollution by sulphur and nitrates

This aspect is clearly the most lethal menace for the whole Venetian Building. Nitric and sulphuric anhydrides are released in enormous quantity from the funnels that, unlike the exhaust pipes of land vehicles, are legally lacking in any system to filter the fumes.

Those particular fumes from the ships come from engines burning heavy oil (bunker fuel).
Would it even be the "normal" diesel fuel for wheel vehicles, we must count that a ship engine gives power from 40.000 up to 120.000 HP, where to move a TIR 4 or 500 are enough.
To the ships fumes, we must add that the ships passengers (around 3000 in some single cruisers), are collected by swarms of smaller engine boats, and moved on these polluting means of transport inside till the smallest veins of the Holy and Historical city and of the Islands. And that the profits from these traffics induce the local people to own more and more pleasure boats with more and more powerful engines...

The Venice Public Health Committee has collected and published a large amount of evidences about this argument, on the site http://www.ourvenice.org. The crumbling of stones by sulphation is also illustrated in other articles of Venice ObServer like the one you are reading now.





The terrific frequence and entity of ship traffic in St. Mark's Basin and in the Canale de la Giudeca.









Wave motion

The impact of the enormous water masses displaced by the run and the manoeuvres of the big ships hits Venice substantially in four ways:

With percussion work when the visible wave breaks on the banks:
this causes heavy damages to the embankments.
With seismic motion when the water mass, moving as a whole, exercises pressure on the small islands:
this causes oscillations and vibrations on the buildings: the wave, aside the pressure, carries the low frequence vibratory motion of the engines, causing disruption to foundations and to the underground channels, like the rio ters and the sewers.
With infiltration and percolateing:
Both the waves attack the substratum and the foundations removing material.
With the turbulences:
mainly caused by the violent manoeuvres of propellers and turboprops, the turbulences, overall those related to docking and sheer off, are major responsibles of the subtraction of bearing base from the embankments. Raising the mud, indeed, the waves move it away and create cavities, like it seems to happen now on the Zattere as can be seen at http://www.ourvenice.org/Venezia_gessificazione/docs/Futuro_Banchina_Zattere.pdf.
The turbulences generated by axial propellers, with their water jets pointing directly against the banks cause disruption on the embankment system typical of our Historical Port, made of large Istria stone blocks.






The turbulences move away the ground base of every building.

It is very important to comprehend that the ships are not, the Venice enemy; on the contrary, this City has always been a naval one. Repubblica Marinara, one of the four Italian.

The ships grew more and more modern and big, but the local ruling class, too much engaged in internal power struggles and party greed, has not been able to update the sea vocation of the city in pair with the times and the development of the international fleet. Notwithstanding the fact that many of the greatest cruise ships are still assembled in the Venetian shipyards, as happens since more than one thousand years.





Serious damages at the embankements caused by visible waves impacts.










Aside on the right, the impacts of the "mute wave" recorded as miniseisms by the marigraph located at the base of St. Mark愀 Bell Tower



Sign the Petition for the Public Health Committee in Venice