The official depth of the Seine in Paris is measured not from the river bed, but from a point on the pont Austerlitz, but Parisians have their own unofficial marker - a statue on the Pont de l'Alma.
As reported, at 6am on Thursday, the level of the Seine at pont Austerlitz was recorded at 5.4m - well above its normal mark of between 1m and 2m at that point. The water is currently rising at about 2cm an hour and is expected to peak at 6.2m on Saturday.
But a more visual clue is the statue of Le Zouave on Pont de l'Alma, which was unveiled in 1856, and is a regular on TV news reports when the Seine floods.
On en parle ds tous les médias... n'empêche que le zouave du Pont de l'Alma a les genoux ds l'eau. Et Louvre en gde partie fermé auj (dept islam, dpt copte, cour Puget, aile Richelieu...) pic.twitter.com/oOP73gx2rQ— Doudou de La Vallée (@DoudouDeLaValle) January 24, 2018
The statue, carved by Georges Diebolt, represents soldiers of the French regiments of North Africa who fought during the Crimean War between 1853 and 1856. It was commissioned to mark French forces' victory in the Battle of the Alma in September 1854.
According to Le Figaro, there were originally four statues - the Zouave was accompanied on the bridge by an artilleryman, a grenadier and a ranger, but the other three statues were removed when the bridge was rebuilt in steel in the early 1970s.
It has become customary for Parisians to use the Zouave to gauge the level of the Seine. According to tradition, when the feet of the 5.2m tall, 8 tonne statue is under water, the river is flooded but there is no danger. When its knees are covered, the capital's quays are closed and river traffic suspended. On Thursday morning, the water was approaching the statue's waist.
Le Zouave du Pont de L'alma, inondation 1910 - 2018 pic.twitter.com/W0h8rAHAzz— Bellot Valerie (@BellotBellot) January 24, 2018
Sadly, the Zouave is not a reliable indicator of the level of the Seine. In the 1910 floods, the Seine in Paris reached 8.62m above normal levels. One of the images was taken as the waters neared their peak.
But, when the bridge was rebuilt in 1974, the statue was raised several dozen centimetres.
This has not stopped locals relying on the 19th-century work of art as an indicator of the state of the Seine. And it has become a cultural icon of the city. It has featured in novels, songs, is a favoured curse of Captain Haddock in the Tintin stories - and, today, le Zouave even has its own Twitter account.
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