The Rough Guide to Venice and the Veneto

ebuilt, reintroducing industry and modern housing On the one hand, Venice
desperately needs the income from tourism, and on the other its population has
halved since the war and its houses are in such a state that 40 percent of them don’t
have adequate bathrooms.
Flooding – and the barrier
On November 4, 1966, the waters of the Adriatic, already dangerously high
after two successive high tides had been prevented from receding by gale-force
southeasterly winds, were disturbed by an earth tremor. The resulting tidal wave
breached Venice’s Murazzi (the sea walls), and for the next 48 hours the sea level
remained an average of almost 2m above mean high tide – in other words, more
than 1m above the pavement of the Piazza, the lowest point of the city. Venice
was left with no power or telephone lines, and buildings were awash with filthy
water, mud and oil from broken storage tanks.
Outside Venice, the flooding did not immediately provoke extreme concern,
partly because floods in Venice were nothing new (at the height of the crisis
national radio simply announced “high water in the Piazza San Marco”), and
partly because attention was focused on the same day’s disaster in Florence, where
a flash flood killed several people and caused massive damage to numerous works
of art. Nobody was hurt in the Venice flood and no artefacts were lost, but the
photographs of water swirling through the doors of San Marco and around the
courtyard of the Palazzo Ducale did highlight the perilous condition of the city.
When floods almost as bad occurred in the following year, the international campaign
to save Venice was already gathering strength, and similarly severe floods in
1979 and 1986 kept the situation in the public eye.
Called the acqua alta (high water), the winter flooding of the city is caused by a
combination of seasonal tides, fluctuations in atmospheric pressure in the Adriatic
and persistent southeasterly winds, and has always been a feature of Venetian life.
With a surface area of some 550 square kilometres, the Venetian lagoon is the
largest in Italy, and with an average depth of just 1.2m this large body of water is
very sensitive to the vagaries of the climate. In recent years, however, its sensitivity
has increased markedly. Between 1931 and 1945 there were just eight serious
acqua alte; in the last decade of the twentieth century there were 44. By 2002 the
number of annual floods had risen to 110 – most of them minor, but the statistic
is nonetheless indicative of a relentless trend.
A rise in sea level has played a part in this, but the rise so far has been too small
to account for the drastic increase in the frequency and severity of flooding. At the
ancient port of Aquileia, not far from Venice, the height of the Roman wharves
relative to the water seems to indicate that there has been no substantial change in
sea level since they were built, while excavations of building foundations in various
parts of Venice indicate that the notion of a general subsidence is unfounded.
Thus the worsening floods would seem to be largely a local phenomenon related
to recent changes in the balance of the lagoon.
Certainly the workings of the lagoon have been interfered with in an unprecedented
way during the twentieth century. The extraction of water and natural
gas has caused some distortion of the underlying strata, and large areas of land have
been reclaimed, both for industrial sites on the periphery of the lagoon and in central
Venice itself – notably around the docks and the Tronchetto car parks. Nowadays
only about 70 percent of the area that was under water in 1900 remains submerged.
At the same time, channels have been deepened to allow huge industrial
CONTEXTS
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Conservation and restoration
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