Paris is experiencing another flood, reminding us of a fact that we tend to suppress: the City of Light historically has experienced a super flood more or less every century, and the last one was in 1910, which now puts us in overdue territory. Could this be the start of the next big one?

It is impossible to know in advance, but if you consider that January is not yet over and that on average May has more rain than any other month in Paris, it cannot be ruled out. That is mitigated by the fact that February and April are the months that average the least rainfall.

Flooding is actually a regular feature of Parisian life (1910, 1924, 1945, 1955, 1982, 1988, 1999, 2001, 2016 and now) and to keep track of the severity of each event, its citizens turn to a popular barometer: the Zouave statue at the Alma Bridge. In 1910, the Seine reached the upper part of his chest at 8,62 meters. It is today at mid-thigh, 6,12 meters, a level also reached in 2016.

The difference between the two levels is only about 2,50 meters, but the difference in impact is unbelievable: in 1910 five hundred hectares (1250 acres) of Paris and 20,000 of its buildings were submerged, and 150,000 people required shelter. A majority of factories shut down, and most of the public transportation network of the RATP, as well as the rail network connecting Paris with the rest of France, stopped functioning. In addition, 30,000 homes in the suburbs were submerged. Damages from the 1910 flood are estimated in today’s euros at 17 billion (US $ 21 billion).

Because of the extent of that catastrophe, ambitious plans to divert some of the flow of the Seine, when needed, were implemented later, but they have never been tested. Four artificial reservoir basins were created in the outskirts of Paris, with a storage capacity of about 830 million cubic meters of water. As impressive as it sounds, it is estimated that between 3 and 4 billion cubic meters of water flowed through Paris in 1910. It is further estimated that diverting water to the reservoirs would only lower the level of the Seine by 70 centimeters.

It is also believed that further efforts could be implemented to gain another 40-centimeter drop. Will they be?