Last month, Venice was hit by three back-to-back floods in less than a week. They sent waist-high water flowing through the Italian city, threatening its iconic Saint Mark’s Basilica and other historic structures. More than 85% of Venice was inundated. The flooding was second only to the waters that inundated the city in 1956, when levels crossed 6 feet.
Venice’s huge Saint Mark’s Square was submerged by more than a metre of water, while the adjacent Basilica was flooded for the sixth time in 1,200 years – but the fourth in the last 20 years.
The floods were primarily driven by the aqua alta, or high tides, which is an annual phenomenon here. But other factors such as climate change and sea level rise made it worse. Experts say that floods of such intensities could become frequent in the coming years.
What is a flood?
A flood is a natural event when an area gets submerge under water for a while. Some floods can occur suddenly and recede in no time. Others take days or even months to build and recede.
Floods can develop in many ways. Heavy rain is one of the major reasons. If it rains hard enough or long enough, low-lying areas get inundated. The flow exceeds the capacity of waterbodies such as rivers, lakes and oceans. When water overflows beyond their boundaries, it leads to flooding. Breach in dams can also cause flooding.
Storm surge – abnormal rise in seawater level during a storm caused primarily by winds – causes the sea to rush inland.
Floods are destructive in nature as huge amounts of water get discharged, leaving no time for evacuation. Sometimes, floods are triggered by other natural disasters such as earthquakes and tsunamis.
What makes an area susceptible to floods?
Any plain low-lying area adjacent to a river or lake is more likely to experience floods whenever the water level rises – for example, a coastal city or a city with a river running through it.
A place’s susceptibility to floods also depends on the capacity of the catchment areas the volume of water hat a river or canal can hold without overflowing. When the amount of rainwater exceeds this capacity, floods may occur.
What is Venice like?
Venice is situated on a group of 118 small islands that are separated by canals and linked by over 400 bridges. The islands are located in the shallow Venetian Lagoon at the head of the Adriatic Sea in Northern Italy. The whole city is an extraordinary architectural masterpiece. The lagoon and a part of the city are listed as a UNESCO World Heritage Site.
Picture Credit : Google