Tourists and residents have been allowed back into St Mark’s Square in Venice a day after it was closed due to exceptionally high tidal waters that swept through most of the lagoon city’s already-devastated centre.

Despite sunny skies, the city remained on edge on Saturday due to possibly more wind-propelled high tidal waters during the weekend. The city was struck on Tuesday by devastating floods, the worst in decades.

By late Saturday morning, water was rising again in St Mark’s Square and the forecast for Sunday was worse. The tide was expected to peak at 1.15 metres (3.7ft) above sea level on Saturday at noon.

Late Tuesday, water levels in Venice reached 1.87 metres (6ft 1in) above sea level, the highest flooding since 1966.

On Saturday, tourists sloshed through St Mark’s Square and strolled across it on raised walkways.

Luigi Brugnaro, the city’s mayor, estimated damages from the flooding would reach at least one billion euro.

He said a final tally of the damage to homes, businesses, stores and the city’s rich cultural heritage would be done once the city dries out, according to Italian media.

“Venice is once again being watched by the world and it needs to show that it can succeed and pick itself back up,” the mayor said in an interview with the Gazzettino and Messaggero newspapers.

Mr Brugnaro said Venice was setting up programmes to help cover damages sustained by individuals and businesses, noting that families could expect up to 5,000 euro and businesses up to 20,000 euro in aid.

He said businesses and individuals suffering even more serious losses could possibly qualify for aid covering up to 70% of damages.