In Hong Kong, Bahrain, America, Portugal, Bordeaux or Arles in France; his firm founded in 2007 in Brussels was already in demand all over the world before being selected at the end of June by the City of Paris to design the future forecourt of Notre-Dame, by 2027.

But the 47-year-old landscape architect sees in this project the perfect opportunity to further increase the visibility of his work, which he sees as «a laboratory of experiments» to «invent a kind of urban ecology», and to vegetate. public space well beyond a few squares.

«Our ambition is to transform the city to make it resilient, habitable, pleasant,» Bas Smets told AFP.

«And if we manage to do it on the Ile de la Cité, around Notre-Dame, we can do it everywhere», he continues during a meeting in his office, in an open space with a panoramic view of Brussels where it employs around twenty young people.

In Paris, on a site frequented by tourists from all over the world, Bas Smets wants to develop the wooded lawns on either side of the cathedral, and «imagine the forecourt as a clearing», in the middle of which water from rain collected in a tank would run off on the ground in high heat, on a very slightly inclined slope.

«There will be ephemeral reflections to photograph, and this will produce the effect of a summer shower which refreshes the air», continues this Dutch-speaking Belgian, a graduate of the University of Louvain.

«We can also imagine that this runoff becomes a daily meeting of a few minutes, like the twinkling of the Eiffel Tower», he adds.

Construction is due to begin in 2024 after the Olympic Games and the completion of the renovation of the building itself, badly damaged by a spectacular fire in 2019.

– Inspired by Central Park –

In terms of sources of inspiration, Bas Smets cites the New Yorker Frederick Law Olmsted, who between the end of the 19th century and the beginning of the 20th century designed a number of urban parks in the United States, including the famous Central Park in his hometown.

«He thought about storing water to bring nature to the city, organized green spaces in a network by linking them together. He was almost already thinking about the climate before global warming (global warming)», smiles the one who likes to describe as «landscape architect».

For its projects around the world, the Bas Smets office relies on local collaborations, and the Brussels resident benefits from the advice of specialists for botany, including that of the Italian neurobiologist Stefano Mancuso (author of «The intelligence of plants») , met six years ago in Florence.

The reflection with them focuses in particular on the need to choose vegetation adapted to the nature of the soil and the climate. And which will undoubtedly have to be more resistant to the heat and to the episodes of drought likely to multiply in the future.

For the «planted promenade» created on a square in the city center of Waregem, Belgium, Bas Smets chose hackberries, a southern species. «I had to fight because we were off the list of native plants», he says, «but in 50 years a hackberry is more likely to have survived than a tree here».

He ranks this achievement among «the exemplary projects that show that we can think differently»… his formula for defining everything he undertakes. Bas Smets must also transform and green the Brussels Central Station district in the coming years, where he deplores the lack of tree-lined avenues.

«To consider a response to climate change is very difficult because it seems inevitable. My hope is that cities all act at the same time to create these ecological reservoirs, he argues.

«But it has to be done now, not in ten years.»