The Seine has turned into a powerful muddy torrent that has submerged parks and footpaths alongside its channel that runs through the French capital, while river boats are no longer able to pass under the city's bridges.
It has risen to a height of 4.57 metres (15 feet) on a scale used to measure the height of the river, several metres higher than its normal level, but below the peak of 6.1 metres (20 feet) in 2016 and the record 8.68 metres (28 feet) in 1910.
On France's border with Germany, officials were preparing to divert the Rhine into a 600-hectare (1480-acre) flooding containment zone if necessary, with potential snow melt adding to the risk of flooding.
Twenty departments were placed on orange alerts over the rising waters in France, with officials warning the flooding could also prompt power outages, while several dikes were also said to be at risk of failing.
In the town of Ornans in eastern France, a siren Monday morning warned residents of the rapidly rising Loue river.
"The main street is flooded, and the ground floor at city hall is underwater -- we haven't seen such flooding since 2002," the town's mayor, Sylvain Ducret, told AFP.
Rescue workers in the region were being kept busy, mainly to ensure people didn't drive on flooded roads and help people whose homes had flooded.
In the nearby department of Meurthe-et-Moselle on the border with Luxembourg, rescue services said the damage had been minor so far.
"The rivers aren't rising quickly but steadily after the continued rain these past few days," the CODIS emergency operations centre for the department said.
"Nothing dramatic, for now," it added.
About 50 people in the coastal Normandy town of La-Riviere-Saint-Sauveur (population 1,500) were evacuated because of the flooding risks, while overflowing rivers had cut off about a dozen roads near Pont-L'Eveque.
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