Zero net artificialization: three decrees published while a report highlights the key role of habitat in the artificialization of land

The “Climate and resilience” law of 2021 aims for “zero net artificialization of soils” (ZAN) in 2050, with the intermediate objective of halving the consumption of natural, agricultural and forest areas (Enaf) by 2031 .

More than 20.000 hectares are artificialized each year in France, or nearly five football fields per hour, which contributes to the collapse of biodiversity, disrupts the water cycle and reduces carbon storage.

The new decrees take into account the law adopted on July 20 to facilitate the implementation of the ZAN.

The first concerns the new soil nomenclature, which defines which soil is considered artificial or not, and from what surface area.

Surfaces “vegetated for park or public garden use” are not considered artificial, as are vegetated surfaces on which photovoltaic panels will be installed.

On the other hand, “herbaceous vegetation for residential use” areas are considered artificial.

In a press release, the ministry recalls that this nomenclature does not apply “to the objectives of the first ten-year tranche (2021-2031)”.

Municipalities and intermunicipalities will have to produce a soil artificialization monitoring report every three years.

The second decree concerns the implementation of these objectives on the ground, called "territorialization", which takes into account the specificity of mountain municipalities or coastal municipalities faced with receding coastlines.

It also takes into account past efforts and the "communal guarantee", a sort of "right to build" of at least one hectare, allocated to municipalities, and mutualizable with others.

Buildings dedicated to agricultural activities are also subject to a separate count while the consumption of space resulting from regional-scale projects can be shared at the regional level.

The third decree establishes a regional conciliation commission.

These decrees were prepared in concert with associations of elected officials, in particular the Association of Mayors of France, which in June 2022 attacked the two decrees implementing the Climate law, judging that they had been published without a study. impact and in a “rigid recentralization” approach. The association had partially won its case before the Council of State.

“We maintain a strong ambition while hearing the concerns of local elected officials on the concrete modalities,” said Minister of Ecological Transition Christophe Béchu on Tuesday, quoted in the press release.

A report highlights the key role of habitat

Housing construction is the main factor in land artificialization, with 63% of space consumed between 2011 and 2021, according to two notes devoted to the "zero net artificialization" of land (ZAN) objective, published Tuesday by France Stratégie.

Over the last twenty years, 80% of this artificialization has taken place on agricultural land.

Drawing up an overview of artificialization, the government prospective analysis body notes "unevenly distributed dynamics" geographically, with the territories located around metropolises or on the Atlantic coast being much more consuming of space. But they also concentrate more inhabitants and jobs.

The authors report a continuation of artificialization, which however increased from “30.000 hectares per year over the period 2009-2011 to around 20.000 hectares since 2015”.

Housing is by far the primary factor in artificialization. Low-density operations, of less than eight housing units per hectare, are even “responsible alone for 51% of space consumption” between 2011 and 2021.

At equivalent land consumption per new home, the expected drop in demographic growth should, however, “make it possible to reduce the consumption of space for housing by around 17% between 2021 and 2031 compared to the previous decade”, predicts France Stratégie .

There is still significant room for progress in the fight against artificialization. Over the past decade, 60.000 hectares could have been saved, particularly in municipalities that have lost households, which corresponds to 26% of the hectares consumed over the period, notes this first study.

The cumulative level of consumption of natural spaces over the last decade also seems "more linked to the sum of small projects in rural communities than to large projects in urban areas".

Intermediate urban centers proportionally consumed the most space, "with a median value of 22 ha/year/municipality when large urban centers consumed around 9 ha/year/community in median value and municipalities with dispersed and very dispersed approximately 2 ha/year/commune".

In a second note devoted to regional strategies, the public body recalls that the regions have until November 2024 to integrate their land sobriety objective into their regional development plan (Sraddet).

All the regions took up the subject, some proposing a reduction in "lesser" artificialization for dynamic territories in terms of jobs and households, while others chose a territorial rebalancing by asking for a lower reduction in the territories not very dynamic in the past.