The sea level is rising, and it's not going to stop.

The risks are well known since the latest IPCC reports, and we know that all the coasts of the globe will not be affected in the same way, but action remains to be taken.

According to official figures, 864 French municipalities are "more particularly vulnerable" to marine flooding, phenomena of temporary flooding of coastal areas by the sea, especially during storms, which will increase with the rise in sea level caused by global warming. climatic.

And 1.5 million people live in these coastal floodplains.

Faced with these risks, the Climate and Resilience Law of 2021 provides for new provisions for municipalities on the front line, and the government has just published an initial list of 126 priority municipalities.

The majority are located on the Atlantic and Channel coasts (notably 41 in Brittany, 16 in Normandy, 31 in New Aquitaine), and the list will be revised at least every nine years.

Two maturities targeted, at 30 and 100 years

Those of the 126 municipalities that do not yet have a "coastal risk prevention plan" will have to carry out the mapping of the evolution of the coastline at 30 and 100 years.

These two horizons also apply to the constructability of land.

In areas exposed to the 30-year horizon, new construction will be prohibited, but with exceptions for the extension of existing buildings or the installation of public services and new economic activities requiring “immediate proximity” to the sea Areas over a 100-year horizon remain constructible, with an obligation to demolish in the long term when the threat approaches.

“It interested me to know the points of vulnerability of the municipality and to be able to say to the population “be careful we are in very sensitive areas”, comments the mayor of Trégastel (Côtes d’Armor) Xavier Martin, welcoming the funding. by the State of 80% of the cost of these maps, which it sees as a tool for "anticipating risk".

But future constructions are not the only ones affected by adaptation to sea level. useful to renovate it today, shouldn't we think about seeing it differently?

“, adds the city councilor.

Elected officials and activists wonder about funding

To allow local authorities to launch this new land development, an ordinance published at the beginning of April creates a new type of lease granted by the State or the municipalities in the band concerned, ranging from 12 to 99 years with early termination depending on the situation. 'erosion.

But the National Association of Coastal Elected Officials regrets certain "legal vagueness" which "suggests many disputes, likely to harm the achievement of the stated objectives".

"The progress that results (from inclusion on the list) remains mainly at the level of raising awareness of the risk", estimates Vincent Bawedin, in charge of the management of the coastline at the Community of municipalities of the Great Lakes, which includes the coastal town of Biscarosse (Landes).

Funding for the relocation of endangered properties remains pending.

"Questions arise about who supports the displacement of the population of the affected dwellings", adds Pascal Laporte, assistant for town planning in Plérin (Côtes d'Armor).

Environmental activists also remain skeptical about the publication of this list.

"These 126 so-called priorities are ridiculous compared to the 864 municipalities threatened", regrets Elodie Martinie-Cousty, of the NGO France Nature Environnement.

“We let too much build on the coast” and the new provisions “are not adapted to the challenges”, she believes.

World

New Zealand: Sea levels are rising faster than expected, study finds

Planet

Climate change: Will oysters survive in a warmer, more acidic ocean?

  • Planet

  • Global warming

  • Sea

  • Littoral

  • IPCC

  • Communes