Venice floods more than one hundred times a year. At the beginning of this month, Venice was caught in another onslaught, as the sea level around the city rose higher than most people can remember. The last time locals and countless visitors had to wade through water this deep was over thirty years ago. It is floods like the most recent one that make it clear how important a flood barrier really is.
Things were different a century ago when floods occurred at an average of ten times a year, but Venice has always been sensitive to changes in water levels because the city itself is built on hundreds of small islands. It doesn’t help that Venice is sinking a few centimeters every year, as well.
One proposed solution comes in the form of a barrier that would use hydraulic pressure to raise steel plates that cut off the rising water flow. This controversial Moses Project-named after the religious figure who parted the red sea-was originally shelved because of the 4.2 billion dollar price tag and the millions (if not billions) of dollars it would take to maintain the structure annually. The hefty price tag isn’t the only cause for concern, environmentalists worry that the artificial barriers will harm protected ecosystems. They claim that closing off the tide flow will cause water to stagnate and kill off marine life.
In an in-depth article by the Times, journalist Richard Owen explains that the project “involves 79,300-tonne hinged steel panels or “buoyancy flap gates”, which most of the time will lie beneath the water but will fill with compressed air when the high-tide alarm sounds, closing off the three inlets. There are 700 workers at the three construction sites, a workforce due to double as completion approaches in 2012. A €1.5 million simulator at Malamocco shows how the locks will allow shipping to pass when the lagoon is blocked off.”
Any barrier that affects the natural flow of floods and tides will obviously have an impact on the underwater ecosystems. The question is how much of an effect? Not only that, but shouldn’t the ancient historical architecture be protected as well? Either way, Moses is currently scheduled for completion in 2012.
|Overall land subsidence in the region surrounding Venice has
been 1.5 to 2.0 meters during the past 70 years, making high
tides far more problematic (ref. Wessex Institute).