Italian Prime Minister Silvio Berlusconi has said that work on an underwater dam designed to protect Venice from flooding will go ahead, despite protests from the city’s mayor and a number of environmental groups.

Work on the US$5.4B project, known as Mose (the Italian name for Moses), began in 2003. It involves the construction of 78 flood barriers, measuring 20m wide and up to 28m high, which will be fixed to the seabed at points where Venice’s lagoon meets the Adriatic sea. The barriers can then be raised when high tides threaten to flood the city.

However, environmental groups are concerned about the rising costs and environmental impacts of the project. According to Reuters, Venice’s Mayor Massimo Cacciari wants other measures to be considered, arguing that the structure could cause more damage than the floods the city currently suffers. The World Wildlife Fund Italy says that shutting venice’s cargo port and barring cruise liners from entering the lagoon would be more effective in controlling the waters.

Earlier this month, protests were held at the project site, and environmental groups announced they were taking further action at the European Union.