Monday, November 21, 2005

Yet Another Plan to Keep Venice Above Water

Yet another scheme to raise Venice above the floods is being considered. The story that follows comes from the Associated Press:

New Idea: Inject Sea Water to Raise Venice

By MARTA FALCONI
Associated Press Writer

ROME (AP) -- A group of engineers and geology experts said Monday they are considering injecting seawater under Venice to raise the waterlogged Italian city by one foot to rescue it from the tides and floods that bedevil it.

That would enable Venice to regain nearly the same height it lost in the last 300 years, said Giuseppe Gambolati, the head of the project.

The $117 million project entails digging 12 holes with a diameter of one foot within a six-mile area around the city, and pumping seawater into the ground at a depth of 2,298 feet, said Gambolati, an engineer and professor at the University of Padua.

The seawater is expected to expand the sand that lies underneath, which combined with a topping of waterproof clay would eventually push up the soil, Gambolati said.

Gambolati said the experts were first planning to test the project on small area.

"If the pilot project proves successful, we will see an immediate benefit, even though gradual, while the complete elevation will be achieved in around 10 years," he said.

The project is still in its initial phase and it will have to be discussed and evaluated by various city, regional and state commissions before being approved.

The final version would be in addition to a much-publicized plan to build a flood barrier to ease the effect of high tides.

However, Gambolati's plan has its critics, including Michele Jamiolkowski, a professor of geotechnic engineering at the Turin Polytechnic, who warned the project requires years of research and millions of dollars before it can even come close to reality.

"We are really in the area of science-fiction," said Jamiolkowski, who also chaired the committee that oversaw the project to stabilize the Leaning Tower of Pisa. "This project is not something very realistic."

Jamiolkowski, who was asked for an independent evaluation by a group linked to the municipality of Venice, said such a plan would probably only raise the city by about six inches, thereby providing little respite from the rising tides. It also could cause parts of Venice to raise unevenly, "and this is absolutely unacceptable for buildings, especially historical buildings," he said.

Venice is threatened by water on several fronts. The city is sinking while the level of the Adriatic Sea is rising and high tides are becoming more frequent, flooding into famed St. Mark's Square and prompting officials to set up raised walkways.

The decades-old debate on how to save Venice from water brought approval in 2003 of a vast project to build a flood barrier to ease the effect of high tides. Dubbed "Moses," after the biblical figure who parted the Red Sea, the project calls for hinged barriers to be built in the seabed just off Venice that could be raised when high tides threaten the city. Completion of the $5.2 billion project is expected by 2010-11.

Giovanni Mazzacurati, the president of the New Venice Consortium, the agency overseeing the Moses project, said careful testing on the new plan will be needed to verify its most critical point - the evenness of the elevation.

"Venice is in a delicate situation, its structure is very fragile," he said. "Should parts of it be elevated in a different way, this would cause the city to crumble."

Gambolati said that, according to his preliminary studies, the project is not expected to affect Venice's stability.

The two experts also said that the new project will not conflict with Moses, but would simply be an additional help should there be any future rise of sea levels.

2005 The Associated Press. All rights reserved.

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