MOSE Project

Tourists cross makeshift walkways in the flooded Piazza San Marco during December 2008.

Franco Debernardi/Getty Images

Some projects never seem to finish. This one can't get started. The MOSE Project -- named after the biblical Moses and the acronym Modulo Sperimentale Elettromeccanico (or experimental electromechanic module for non-Italian speakers) -- is the result of 30 years of negotiations first begun after Venice experienced a catastrophic flood in 1966.

The project hopes to stem flooding and save the city from sinking deeper into the lagoon on which it's located. In the last century, Venice has sunk 11 inches (or about 28 centimeters) [source: Poggioli]. And whereas in the early 20th century, Venice experienced flooding about seven times a year, it now happens around 100 times a year [sources: Poggioli, BBC News].

MOSE calls for 78 hinged metal gates to be placed along three channels in the Venice lagoon. The gates could be as large as 66 feet (20 meters) wide, 16 feet (5 meters) thick and 92 feet (28 meters) long [source: Squires]. The 300-ton (272-metric ton) gates mostly will be on the seafloor. But when water levels reach a certain level, the barriers will automatically fill with air, rising within 30 minutes and creating a dam 0.93 miles (1.5 kilometers) long. When the waters recede, the gates can descend back to the seafloor in 15 minutes.

Like many projects of its type, cost estimates vary wildly -- from $5.5 billion to $10.4 billion [source: Squires].

­Construction finally began in May 2003 and should be finished in 2012, but environmental groups and maritime-related businesses have raised concerns about the project, so the work is far from done.