Since he opened his firm in 2007, Smets has specialized in taking hyper-urban, often desolate, sites and turning them into eco-friendly oases. For LUMA Arles, an interdisciplinary creative campus in Provence, he transformed a onetime industrial rail yard into a lush 27-acre park, with more than 500 trees and a rain-fed pond to irrigate the plants that cool the grounds in the blazing summer months. In Brussels, he turned another disused rail yard into the 30-acre Tour & Taxis Park, planting 3,000 pioneer trees and using the former train-track ballast for an underground reservoir.
And for Notre-Dame, Smets will double the number of trees to create more shaded areas, planting varieties that, he said, “resist higher temperatures, require less water, and can stand longer droughts,” like European nettle, maple, and hornbeam. He is enhancing soil to retain water, “like an artificial aquifer.” He is converting part of the underground parking lot into a 34,000- square-foot visitors center, with a view of the Seine, to welcome tour groups that used to congregate on the parvis. And in the other part, he is building a cistern to capture rainwater for irrigation and a wave feature less than a quarter of an inch high that sporadically washes across the parvis to lower surface temperature by 18 degrees Fahrenheit and air temperature by nine.
On hot days, it can be activated repeatedly. “We want to create a magic moment, when there is an ephemeral mirror reflecting, briefly, the cathedral,” Smets said, and he hopes it will become “an event that people come to see, like the twinkling lights on the Eiffel Tower.” Construction of the $50 million project will begin in late 2024 and is scheduled to take three years. “We have to rethink public spaces and cities as an urban ecology,” Smets said. “If you can do it in Paris at Notre-Dame, you can do it anywhere.” bassmets.be