Pressure is mounting for a solution to the on-going dispute over whether cruise ships should be allowed into Venice as more cruise lines pull out of the city.

Venice Port Authority is expecting just over 10 per cent fewer cruise ships this year (470 vs 529), with passenger numbers down 11.4 per cent to 1.4 million and a corresponding fall in income.

Port Authority president Pino Musolino said that over the past two decades the cruise sector has been a significant source of income for the local population and Venice hinterland.

“Venice is losing passengers and ships. That is not just a problem for our city but for other ports in the Adriatic as cruise ships are only visiting them on their way to Venice,” he said.

Venice Port Authority is expecting just over 10 per cent fewer cruise ships this year Credit: HildaWeges hilda.weges@chello.nl/Hilda Weges

P&O Cruises has pulled out of Venice this summer, while Holland America Line has relocated a ship from Venice to Alaska. Cunard is visiting the city just four times this year - compared with five last year - and twice in 2018.

The drop in numbers is welcome news for environmentalists, who have been campaigning for years to stop cruise ships, some 10 or more decks high, sailing along the Guidecca Canal to reach the port - a route that takes them within 1,000 feet of St Mark’s Square.

Venice in Peril chairman Jonathan Keates said it is ‘absurd’ that ships which tower over the bell tower in St Mark’s Square are allowed to navigate the canal.

The presence of large cruise ships in Venice has long been a bone of contention for residents Credit: 2013 Getty Images/Marco Secchi

Modern ship builds have little respect for the scale of Venice but besides visual impact there are big concerns about the damage caused by water displacement and engine pollution.

In response, the port authority said that for several years ships have had to switch to a lower-sulphur fuel – 0.1 per cent compared to a 2020 target in Europe of 0.5 per cent – before entering the lagoon. Regular checks are carried out.

The debate over whether cruise ships should be allowed into Venice is not new but concerns were heightened in 2012 when Costa Concordia capsized off the Italian island of Giglio.

The accident spurred the Italian government to introduce a law that banned cruise ships over 96,000 tons from sailing the Guidecca Canal and limited the number of vessels over 40,000 allowed to navigate that channel to five a day. The law came into effect in 2014 but was thrown out just two months later by a regional court of appeal.

Since then, members of the Cruise Lines International Association have implemented a voluntary ban on sending cruise ships over 96,000 tons to the Port of Venice. CLIA said this will continue until a definitive solution is reached, but the body is adamant that Venice must stay on the cruise map.

In a statement CLIA says: “Cruise passengers represent a small proportion of the total number of tourists visiting Venice each year and on average spend much more per head per day than other tourists.”

That assertion is supported by the Venice Port Authority. Mr Musolino said some 24 million people visit Venice each year, so cruise passengers (1.4m) are a tiny percentage of the total.

Most of the cruisers are embarking or disembarking from ships that sail from or to Venice and may not actually tour the city and its attractions.

Only about 500,000 cruise passengers actually visit Venice during a port call or stay in the city before or after their cruise. They are however, using the airport and taxi services and transfer companies, while cruise lines are paying port fees and the costs of provisioning and fuelling the ships.

Frustratingly for all little has changed in the two years since the ban was overturned. This is despite protests by local residents, pressure groups and Unesco, which had suggested Venice would be put on its list of endangered heritage sites if none of the measures required to protect the lagoon and its delicate ecosystem were implemented.

Unesco has suggested that Venice could be placed on its endangered list Credit: TTstudio - Fotolia

Unconfirmed reports suggest that proposals put forward by Venice mean the endangered list is unlikely to be discussed by the World Heritage Committee this year but as conservation is ongoing it could be back on the table in 2018.

Environmentalists want a new port to be built outside the lagoon, from where cruise passengers would be tendered into the city on small boats. The port authority argues this would not be safe due to tidal fluctuations and instead wants an alternative channel to the port that avoids sailing past St Mark’s Square to be dredged so that it can be used by cruise ships.

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Mr Keates said Venice in Peril opposes dredging new routes through the lagoon as it will damage the ecosystem. However, the plan looks likely to be put to a meeting of the Comitatone, the body responsible for deciding and implementing activities to safeguard Venice and the lagoon, in mid June.

Mr Musolino said: “No one wants big ships sailing past St Mark’s Square but they are important to the local economy so we have to find a solution to manage the economic and sustainability issues.”