After decades of delays, sea walls designed to defend Venice from the occasional king tides that reap havoc on the city and its lagoon have been deployed this weekend to prevent flooding.
In a system that was designed decades ago, but which has been delayed by cost overruns, corruption and opposition from environmental groups, Venice’s MOSE (MOdulo Sperimentale Elettromeccanico, Experimental Electromechanical Module) is a project intended to protect the city of Venice and the Venetian Lagoon from flooding.
The project is an integrated system consisting of rows of mobile gates installed at the Lido, Malamocco, and Chioggia inlets that are able to isolate the Venetian Lagoon temporarily from the Adriatic Sea during high tides. Together with other measures, such as coastal reinforcement, the raising of quaysides, and the paving and improvement of the lagoon, MOSE is designed to protect Venice and the lagoon from tides of up to 3 metres.
Tweet by Mayor of Venice (video):
MOSE barriers consist of flap gates, installed in the bottom of the inlets, that allow for the temporary separation of the lagoon from the sea during an exceptionally high tide. Under the MOSE system, if there is a very high tide, compressed air enters the 78 gates, causing them to rise up and block the tide entering the lagoon.
By 10 am on 3 October, following overnight storms that had swept through southern France and northern Italy, all 78 floodgates barricading three inlets to the Venetian lagoon were raised, and even when the tide reached as high as 1.3m, it is reported that water levels inside the lagoon remained steady.
President of the Confindusria Turismo e Servizi Venezia e Rovigo, Salvatore Pisani posted on LinkedIn: “Today the beginning of a new era .. the Mose is working keeping the city safe .. there is no reason anymore to be worried about high-tide in Venice. Venice and Italy🇮🇹 have blossomed!!”
If the flood barriers had not been raised, authorities say about half the city’s streets would have been under water, and visitors to St. Mark’s Square — which floods when the tide nears 1m — would have been wading in knee-deep water.
The floodgates were tested several times during the summer, but under less demanding weather conditions than those on Saturday. The system will not be fully operational until the end of 2021, when it will be able to defend the Venice lagoon from king tides of up to three metres.
VIDEO OUTLINING SYSTEM: https://youtu.be/bYAysXU0r7o
MOSE website: https://www.mosevenezia.eu/
Photo – top of page: © 2019 Chris 73