Officials carried out the first test of Venice’s flood barriers on Saturday, just days after the Italian city saw its first high tide of the winter season.

Sky News Australia reported that dozens of officials, including Italian Transport Minister Maurizio Lupi, looked on as four enormous, steel floodgates rose from the water to create an artificial barrier. Each barrier weighs more than 40 tons.

“This is a very important and emotional moment,” Venice Mayor Giorgio Orsoni told Agence France-Presse. “This will change the view one may have about the city and its lagoon, because, don’t forget, it is a whole, the city and the lagoon are one.”

The barrier project -- known formally as the Experimental Electromechanical Module project and informally as MOSE -- is designed to keep high tides of as much as 2.7 meters, or about 9 feet, from reaching the city, the Telegraph said. The idea is to have 78 have of these barriers block the three inlets to the Venetian Lagoon. The gates will span more than a mile and be positioned at the three entrances to the ancient city where the lagoon links to the Adriatic Sea.

During flooding, when the water reaches 1.1 meters, or about 3.6 feet, above normal levels, the locks will spring into action. reported the Venice flood barriers will sit in immense tanks on the sea floor. Pressurized air will be pumped into the steel barriers, raising them up on hinges. The buoyancy makes them float, which will keep the floodwater at bay. The air can be deflated once the water has receded.

“The benefit of the city is that no more floods will arrive and that all the ground floors of the city, which are usually washed out and destroyed by these tides, will be safe,” Hermes Redi, CEO of Consorzio Venezia Nuova, which is in charge of the project, told the Telegraph.

Venice sits on a group of 118 small islands separated by canals and linked by bridges. Located in the marshy Venetian Lagoon between the mouths of the Po and Piave Rivers, the centuries-old city is prone to flooding. Every year, the “acqua alta” brings high waters that spill into the streets and walkways of Venice. It happens several times a year, and it has gotten worse over the past century, due in part to Venice sinking by 23 centimeters, or about 9 inches.

The floodwater causes massive damage the city’s infrastructure, and puts many businesses and residents on lockdown until the water recedes.

MOSE has already cost more than $7 billion and its completion is not expected for years, according to BBC News, which reported an additional $800 million is needed immediately to keep 4,000 construction workers on the job.

And the project hasn’t been without its fair share of naysayers, either. Some claim the project is too expensive and that there’s no guarantee it’ll even work.

Construction on the Venice flood-barrier project began in 2003. It was slated to start operating in 2014, but delays have pushed that date back to 2017.