VENICE. The vibrations accurately recorded by the Marigraph of San Mark suddenly rise when large cruise ships pass by, confirming the concerns expressed by the Council of Castello (a Venice quarter) and its residents about the effects caused by the passage of large ships through the S. Mark’s basin. And August is one of the most dangerous months, according to the statistics of the Hydrographical Institute.
The 26th August of two years ago is an example for all. In fact, the situation, as regards the cruise ships, has not changed in these two years.
The marigraph records the tides waves, but also works like a seismograph, recording the water vibrations. After a night without vibrations, the marigraph curve starts rising at approximately 5 in the morning when the “Splendid of the Seas”, one of the cruisers that stops in Venice, enters the S. Mark’s Basin.
After some quietness, another violent vibration occurs at 8.30, when is the Costa Atlantica to arrive.
That day the marigraph records have many ups and downs but a sudden rise occurs at 5 p.m. when the “Rotterdam 6” leaves the basin. The marigraph records the top oscillation just after 6 p.m. when is the turn of “Costa Classica” to leave the Marittima docks and thus pass triumphantly through the S. Mark’s Basin, offering its passengers a monumental picture of Venice.
Afterwards, the marigraph oscillations calm down, as soon as the big cruisers stop passing by the S. mark’s area. But the day after is again the same, with the ships’ passage leaving their trace on the graph. When? At around 8.30 a.m., when again is “Costa Classica” that comes by.
It is an impressive correspondence, regardless the recent assessment of the experts that the Port of Venice has appointed to answer the public opinion’s concerns about these large cruise-ships passage.
The Port experts reasserted that «the 60 tons ships, according to hydraulic experts, only generate a very limited wave motion that cannot be distinguished from the so-called background noise, or the waves provoked by other ships that pass through the Giudecca channel very day».
So it would be that more than the “Mistral” or the “Princess” are the «motor boats, the Actv waterbuses and the police speedboats » that provoke the waves. And how do they explain the vibrations that the S. Mark’s marigraph records when the holiday cruisers pass by?
«It is absurd – says one of the spokesperson of Associazione Arco, an association that gathers the residents of East Castello concerned about the impact of large cruisers in the area – that so many serious problems are caused to local residents and so big risks are put on the City monumental patrimony, only to let the cruising tourists pass through the S. Mark’s Basin. Cruisers can easily pass through the Oil Channel. And in fact, one of the Costa cruisers has gone through the Oil Channel during the Redentore celebrations ».
The motor vibrations and noise emissions are a continuous reason for concern. Arpav – the regional agency for environmental protection – has recognised that the noise level is incompatible and the City Council Environmental Commission has asked an evaluation of environmental impact.
It is still an open issue, a problem that both the City Mayor Paolo Costa and the Commissioner for the water traffic have promised to address.