In an unprecedented decision, the prefecture of the Alpes-Maritimes recently announced that they will not validate local plans in the department if they do not adequately take account of the sustainability of local water resources.

Over the past ten years, several mayors have refused planning applications on this ground.

In the Ardèche in 2023 the prefecture suspended their approval to planning consents in 22 communes on the grounds of a lack of water resources.

In the Alpes-Maritimes local plans will now have to include a forecast of the future balance between the demand and supply of water resources.

If the balance cannot be ensured in the long-term, the prefecture will refuse to give its consent to a plan.

The opinion of the local prefecture in such matters is mandatory.

Although existing planning consents will remain in place local councils will be obliged to have greater regard to the impact on water resources of new planning applications. Developers, in particular, will need to demonstrate that their projects are sustainable.

"The Alpes-Maritimes have experienced worrying droughts in 2022 and 2023," states the prefecture, which recalls that nine municipalities in the department experienced water restrictions and bans in 2022 and fourteen others experienced severe shortages.

"Such episodes could become common in the coming years due to climate change: a drop of about 30% in the flow of the department's rivers is expected by 2050, as well as a drastic drop in the snowpack by the end of the century," the prefecture stated in justifying its decision, which the prefect himself described as a "small revolution."

The Pays de Fayence, which has nine villages perched on hilltops in the Var, decided last year, precisely for fear of water shortages, to limit its population growth and to freeze new building permits for 5 years.

Challenged in court by a real estate developer, the decision was confirmed on appeal by the administrative court of Toulon in February 2024, when the judge considered that the risk to public health was high enough to warrant such a decision.

Mayors already have the power to refuse consents if they consider that water resources are insufficient, but the discretionary power is rarely exercised.

Water authorities are also consulted on planning applications, and they can require that projects are changed to strengthen the water supply network if necessary.

Tom Easdown, MD and architect at French Plans, comments that: "The issue is becoming more of a problem and it is also interesting that there is not only concern for the water used by the occupants once the building has been built but also in the construction phase."