Newly Constructed Flood Barrier, MOSE, could be Venice’s Possible Salvation

Venice, a major city located in Northern Italy, is made up of small islands that have been troubled with flooding since the country’s formation. Unfortunately, these floods have worsened in the past 65 years from rising sea levels due to climate change. In an effort to try to protect Venice from floods, barriers and other machinery have been put in place.

MOSE (Modulo Sperimentale Elettromeccanico) is a barrier system that includes an artificial island that contains a sandbar that blocks the Venetian lagoon from the Adriatic Sea. In different inlets and canals, there lay gates that can help separate the Venetian Lagoon from the Adriatic Sea to prevent flooding. The MOSE barriers can protect Venice’s lagoon from up to three meters of water. Although its invention was first started in 1987, MOSE wasn’t completed until the end of 2021, taking almost forty years.

In October of 2020, these barriers successfully prevented flooding in Venice after a high tide, which would usually, without protection, cause flooding along with significant water damage to the city. Since then, the barriers have been used several times in an effort to keep Venice from being fully submerged in water. So far, the barriers have been mostly effective in preventing the submergence of the city. It took a long time for the barriers to be put in due to reasons like economic struggles and skeptical Venetians. Many doubted its abilities, claiming that the device doesn’t do much then raise its gates for three or four hours at a time.

These barriers work by using a hydraulic method–, using liquid to operate–and mobile gates in an attempt to isolate the Venetian Lagoon from being overflowed by the surrounding sea during high tides and other causes for floods. These gates are considered mobile because they can move on their own. There are 78 of these gates that are divided up into four barriers. Some of these barriers are located in Lido, Chioggia, and Malamocco inlets, each having about 20 gates. When high tides are predicted, the gates are filled with air, releasing water and floating upward until the fins on these gates are above the expelled water, letting no water go over to submerge the islands underwater. After the tides are back to normal, more air is forced into the fins and the air inside is pushed out, keeping Venice dry and safe.

The man-made island that is the base of the operation is located in the northern section of the Venetian lagoon. The unnamed artificial island is where the barriers and gates are controlled. On the island, they also monitor water and tide levels, weather, and any motion detected in the water. The tides are recorded by using red and blue lines that rise and fall to show the tides. This is to ensure that when a change does occur, the proper measures are put into place to keep the city and the citizens safe.

Despite many of these cautions, on December 28th, 2021, there was a problem. The line that shows the Adriatic sea was rapidly increasing, way above the average. Then, the blue line, following the Venetian lagoon, promptly decreased. Due to the change in water levels, they raised MOSE 80 centimeters as an attempt to counteract the tide. This kept the water at ease for 12 hours, but unfortunately, the lines intersected again.

This is a recurring instance. Differing conditions between the sea and lagoon during the months of November and December are not uncommon. Neither is flooding in these months. MOSE is planned to be totally operational in the next year or so, being able to raise when tides hit a little above average.

Overall, these barriers have worked, but there have been some high tides that can't effectively stop. Better precautions need to be put in place to alert when tides are rising, and the gates may need to be able to lift more, to handle a higher influx of water. The MOSE project is constantly working to better their operation in hopes to make it as effective as they can. For now, Venetians will have to keep being cautious and safe during floods.