A color is not just a wavelength but also an idea, a thought. It is an ensemble of sensations and convictions born within a given culture. In the realm of modern architecture, green recalls the nature that modern cities have mistreated for years, giving priority to expanses of cement and asphalt over grass and trees, making this color more rare, precious and desirable.
Nico Zardo
The few urban spaces that have not yet been built on are today object of widespread attention by architects-gardeners trying to propose oasis of greenery, offering new ways to live and enjoy the city. One of the most striking recent examples is London’s Garden Bridge designed by Thomas Heatherwick: a new 366-meter long pedestrian bridge that will unite the banks of the Thames, between Temple and South Bank, giving rise to a hanging garden filled with 270 trees plus shrubs, climbing plants, borders and flowers. An overall surface of 6000 meters, 2500 of which will be cultivated, creating an oasis of green and of tranquility for a maximum of 2500 visitors.
Completion of the works is scheduled for 2018, but the ways the garden bridge will be used are already known: it will be off limits to bikers or to those who intend holding impromptu parties or picnics on it. Instead, it will be made available for private events and the fee charged will go towards maintenance costs, estimated at 3.5 million pounds per year. Although the city’s authorities have already issued permission for the new project, not everyone agrees on the appropriateness of this new work. Some retain that connection between those two sides of the city is already amply provided for by existing bridges (Waterloo, Blackfriars and Millennium); others fear possible construction speculation risks or upsetting the existing landscape. We can only hope in the words of the Mayor, Boris Johnson: “The only purpose of this bridge is to recreate the spirit”.
IF CROSSING A RIVER BY STROLLING IN THE MIDST OF TREES IS CERTAINLY AN ORIGINAL IDEA, enjoying gardens that are more or less suspended is something that can already be done in several cities. Let’s take a look at two of them that have lots in common: the Viaduc in Paris and New York’s High Line. Both these situations have successfully exploited the transformation of a railway that had fallen into disuse, offering citizens the opportunity for a long stroll in the center of the city but away from traffic.
THE FRENCH EXPERIENCE BEGAN IN 1990 when the Mayor of Paris decided to rehabilitate the abandoned viaduct of the railway line that from Place de la Bastille led to Bois de Vincennes. The structure, comprised of large vaults in stone and brick, was reconverted by architect Patrick Berger who, by recovering the volumes present under the arcs, enclosed by glass walls, made room for the ateliers of 50 artisans. The upper portion, where the railroad was located, has become a 4.7-km long “Promenade plantée”. The pedestrian walkway, also called “Coulée verte”, features several different types of gardens extending along a surface of 3.7 hectares. From a botanical point of view, it is interesting to note that in several points along the promenade, spontaneously growing plants born during the period that the Viaduc was abandoned have been deliberately maintained. This makes the promenade very interesting not only for tourists and local inhabitants, but also for scholars.
NEW YORK’S HIGH LINE is a park built in 2009 based on a project by design studio Diller Scofidio + Renfro. For 2.3 kilometers, the park is set on the location of the elevated railway line that in 1930 transported goods on Manhattan’s West Side. Owned by the City of New York, the park was born and managed thanks to the interest by an association of local inhabitants, Friends of the High Line, that at the end of the 1990s opposed demolishing the old railway structure and have worked for its recovery, turning it into a green promenade. The linear trail that unfolds between buildings, about ten meters above the ground, affords a particular view of that part of the city and, like the “Promenade plantée”, it has maintained hundreds of spontaneous plants that prospered there in the sunny, rainy, humid and dry micro-climates along the old roadbed. Six years from its official opening, the High Line has become one of the most sought-after areas of the city: initial forecasts that spoke of 400 thousand visitors a year have been greatly exceeded, attaining an affluence of over 5 million people.
PROPOSALS BY URBAN PLANNERS TO INCREMENT THE PROPORTION OF GREEN IN THE CITY have often gone unheeded, so much so that today, besieged by cement, we look at interventions in favor of greenery as something rare and precious. Among the battles fought in the second half of the last century for the conquest of an architecture in harmony with nature, we can mention the one by Austrian artist Friedensreich Hundertwasser who, in the buildings marked by soft forms and lively colors that he designs, experiments a strong integration between the construction itself and the natural greenery. In those same years, Argentinian architect Emilio Ambasz obtained recognitions and prestigious commissions by raising the issue of having the natural green prevail over the city’s gray. Among his most awarded creations, the Prefectural International Hall in the Japanese city of Fukuoka, a prodigious stepped pyramid completely covered by luxuriant gardens.
BUT PEOPLE HAVE ALWAYS “HUNGERED” FOR GARDENS and the scarcity of the spaces available suggested to the administrators of the city of Chicago in 2001 to build a 6000-square meter roof garden on top of City Hall, featuring 20,000 plants belonging to 150 different species. Besides offering recreational moments to its visitors, the original work uses rainfall for its irrigation needs and at the same time, due to its insulating properties, keeps the building underneath cool. When horizontal spaces are not enough, like in the case of some buildings of the Quai Branly Museum in Paris, thanks to the project by Patrick Blanc, the garden becomes an external climbing plant wall.
ALL THESE EXAMPLES ILLUSTRATE THAT GREENERY AND THE NATURAL ENVIRONMENT ARE PRECIOUS. It is not by chance that, in building their new premises, the most prestigious companies use plants and gardens as elements that make a statement about their power and prestige. A prime example: the new 5-billion dollar Apple headquarters that Norman Foster’s studio is designing in Cupertino, California. A ring-shaped structure measuring over a mile in diameter, a surface area of over 700,000 m2 dedicated to pasture and natural refuge, where 6000 trees belonging to 300 different species will be planted. A splendid natural space for the 12,000 employees, while the public - green with envy - will only be able to admire it from afar, on the other side of the fence.