Residents in storm-hit areas of southern France have been warned not to drink tap water as it may be polluted.
Some residents have already started the clean up
The measure is part of the authorities' response to the high winds and floods that have left five people dead and forced around 15,000 from their homes.
The situation is said to be easing around Marseille, declared a disaster area, but is critical in other areas.
French President Jacques Chirac, who visited the area on Wednesday, pledged 12m euros ($14m) in aid for the region.
Deputy Foreign Minister Renaud Muselier, a regional deputy, told France 2 television there were concerns for the wine-growing region around the River Herault, where the water level continued to rise early on Thursday.
"As far as Marseille and the Rhone Estuary is concerned, we are over the worst. But around the Herault the catastrophe is continuing," he said.
Mr Muselier blamed global warming for the catastrophe, which appears to be a repeat of similar flooding during storms last year.
"It seems clear the climate is changing," he said.
Flood waters and high winds have disrupted road, rail and air traffic and four nuclear power reactors have been shut down due to flooding along the River Rhone.
After his visit, Mr Chirac said: "Faced with this new catastrophe, I would first like to think of the victims, of those who have been lost, of those who have been
evacuated, to tell them that they can count on the nation's
solidarity right now... and afterwards."
But the river level was gradually dropping after reaching record levels on Wednesday and the army was brought in to help patch up leaks in dykes along its banks.
"We have identified several breaches which allowed flooding onto farmland but these are now under control," the Rhone Estuary prefecture said in a statement.
Around a 250,000 people in the Gard region, around the city of Nimes, were told not to drink tap water because the flooding may have made it too contaminated to drink.
Firefighters have had to rescue people trapped in cars, houses and trees by the water.
The Red Cross has set up emergency shelters for around 700 evacuees and the Secours Populaire Francais charity has urged the public to donate to a fund it had set up to help
those hit by the disaster.
Are you experiencing the floods in southeastern France? Send us your stories using the form at the bottom of the page.
You can also send us your photographs of the floods to firstname.lastname@example.org
I am spending the year on a university exchange programme in Marseille. I have had to evacuate my basement apartment and move in with a friend (thanks Helmut, I appreciate it!) The rain is harsh - like nothing I have felt before, and the sheer devastation is breathtaking to see. I want to come home though!
Hywel Davies, UK
Here in the Cevennes we battle to re-route streams above us, but it's pick and shovel versus granite, we are succeeding unlike the valleys below. Up to 30% of the main road D48 has disappeared in several places. Landslides are numerous sometimes carrying rocks of 5 tons plus. Snow already fallen will be the next problem as forecast warm weather defrosts in the days ahead.
Alan, France-30 miles north of Montpellier
Although a couple of hundred kilometres from Marseille it is likewise 'bucketing it down' in our village near Narbonne. Having suffered from two and a half metres of water in our house in October 2002 due to flash flooding we are now intently watching the storm channel which flows through our village. We know what it is like to have been flooded here and our thoughts go out to the people who are now suffering.
Michelle Marsh, France
Living and working in Montpellier, the journey to work this morning was fraught, with flooded roads and incautious drivers. At 11h00 we were sent home as Meteo France raised a red alert (the first?). A number of broken down cars line the roads. The outskirting towns are cut off from us.
It rained all day yesterday and last night - the rain here is not generally the polite English variety but a much more forward Gallic version, with sound effects (son et lumiere indeed!). It is no longer raining - but it looks like the wind will start up.
David K-M, France
Big fires and big heat in the Summer, big floods in the autumn... what next?!
What a rotten year!
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