On the eve of another premature heat wave in France, several water utilities have called for water conservation.

"In order not to get into a difficult situation, we have to prepare ourselves," says a call from the Association of Water Companies published on Monday.

Temperatures of up to 40 degrees are expected in France between Tuesday and Saturday.

The water companies are appealing to the state to modernize the supply, for example by better detecting leaks in pipes and by seasonal tariffs.

"Natural solutions" are also needed, such as better protection of wetlands and the fight against soil sealing.

Technological solutions should also be considered, such as the replenishment of groundwater reservoirs and the secondary use of slightly polluted water.

Restrictions already apply in a good third of France's 101 departments.

Depending on the warning level, the watering of gardens and fields is rationed;

Cars can no longer be washed and private pools can no longer be filled.

Less rain than usual

The energy company EDF has meanwhile announced that it will throttle the Saint-Alban nuclear power plant on the Rhone again because of the low water level in the river.

Production there had already been temporarily reduced from 1,300 megawatts to 260 megawatts at the beginning of June.

In order to protect the biodiversity in the river, the removal and return of the cooling water is strictly regulated.

In the past, French nuclear power plants had to be throttled during hot spells, but this usually happens in midsummer.

At the beginning of May, the Blayais nuclear power plant on the Garonne River was also shut down due to low water levels.

The month of May was the hottest in France since weather records began, with an average temperature of 17.8 degrees.

The highest temperatures were reached in Ajaccio on Corsica with 36.2 degrees and in Albi near Toulouse with 35.4 degrees.

Almost all over the country, the soil dried out more than it normally does until mid-July.

In the past three months, it has rained about 45 percent less than usual.