Géopolitique, Réseau, Énergie, Environnement, Nature
Great Landscapes in Progress Euralens Centralité and the Chain of Parks and La Lisière de Saclay
Issue #4
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Issue

Issue #4

Auteurs

Michel Desvignes

Published by the Groupe d'études géopolitiques, with the support of the Fondation de l'École normale supérieure

Landscapes are often solely approached from the point of view of protection. Their transformation is therefore sometimes considered suspect. Typically, when landscape architects invoke “land” or “geography”, we think of natural geography when it is above all human geography. Our territory is heavily shaped by human activity, practices and relationships.

The distinction between natural and artificial phenomena allows us to envision new transformations. The challenge is not to embellish a difficult legacy, but to benefit from the particular nature of the configurations encountered in order to address contemporary issues.

The conversion of industrial sites inherited from the 20th century, and the reclassification of agricultural and peri-urban land have, over the last few decades, led to major changes in the public space of the future. New challenges are already on the horizon: our urban peripheries will be faced with the decline of commercial areas.

The profession’s renewal, led by Michael Corajoud in the 1970s, was responding to the need — some would say an urgent one — to break free from the status of a “gardener” who works for architects and engineers that landscape architects had been relegated to in the post-war period. The aim was to regain a role in the restructuring and development of territories, towns and public spaces. A few decades later, we can see the relevance of this stance, as landscape architects are now involved in multi-disciplinary teams.

Today, project directors seem to once again believe that landscape can be a decisive element for coherence in land-use and public-space studies. This conviction is increasingly echoed by local communities and politicians concerned, through metropolization, with producing long-term visions for their territory. It can also be found in smaller-scale operational development projects.

This unexpected and considerable progress nevertheless remains fragile and quite modest compared to the developments designed and implemented in the 19th century. Of course, contemporary circumstances differ from the 19th century. Industrial zones have grown, and many have changed. Cities have continued to sprawl, even though the 20th century did not build public spaces on the same scale as these developments. Today’s challenges concern transformation projects. It is therefore crucial to reconfigure existing territorial or urban structures, change their use, and beautify them to create new areas of continuity and missing public spaces.

Our involvement in large-scale territorial redevelopment projects has led us to reconsider the parks system established by Frederick Law Olmsted (1822-1903) in the 19th century in the United States. We have discovered the strategic value of this vast legacy, such as Boston’s “Emerald Necklace”. These parks have shaped the city’s urban structure.

Two of our agency’s land transformation projects exemplify this approach: Euralens Centralité et Chaîne des parcs as well as la Lisière de Saclay. This American landscape architect’s approach, with its geographical foundation, has proven to be a powerful guide for today’s urban planning.

Frederick Law Olmsted’s park system: geographical foundation and urban organization 

Frederick Law Olmsted gave the landscape architect a role and responsibility that distinguished it from that of the gardener. Creating spacious landscapes which offer communal space accessible to all citizens responds to this need. Throughout his career, he developed models designed to counterbalance the burdens of urban life. To this end, he gave urban nature parks a specific purpose: to offer visitors immersion in a natural landscape, free from distractions that might interfere with the restorative experience.

Olmsted was also a writer, influenced by transcendentalist philosophers such as Thoreau and Emerson. His landscapes are characterized by a singular style, and the materials used are in no way those of ornamental gardens, or even the landscape gardens that were being created in Europe at the same time. He worked with woods, marshes, meadows, and bodies of water — all elemental materials deeply rooted in geography and nature. This landscape architect’s work attests to his pursuit of cohesion, in which the whole takes precedence over the individual element or setting. We see his elemental writing, in the sense of elements, as highly relevant to our current awareness of nature and its place in public space.

His parks system is based on a rigorous mapping of geographical structures: a river in Boston or ancient thalwegs that became open sewers in Washington. This park system forms a cohesive, intelligible whole because it is largely based on natural geography while at the same time integrating infrastructure and development elements. In cities, this geography is complemented and transposed by artificial elements. The latter are minor on a geographical scale — which retains its coherence — but they are immense and structuring on the scale of a city’s new districts.

In Minneapolis, the parks system connects the Mississippi River to all the lakes of Minnesota, thanks to more artificial elements. The overall effect is one of a natural geography that extends over about ten kilometers. Sixty kilometers of urban frontage can be seen across a parks system that forms the city’s true defining monument. Similarly, Olmsted’s plan for Boston’s parks system covers a radius of several dozen kilometers. The power of this landscape architect’s work, in terms of implanting nature that structures the city, can be applied on a scale that is completely foreign to us. It is fascinating to take a good look at the dimensions of his designs.

Olmsted’s proposed structural landscapes form a “system” in that their components work together, linking up across the different scales of intervention, from the management of the larger territory to the definition of major or secondary public spaces.

These interlocking scales of intervention, and their gradual implementation, testify to the extraordinary flexibility of these parks systems. Whether it’s in New York, Boston, or Washington, a continuum of ponds, promenades, parks and parkways was developed over a fifty-year period and still forms the backbone of these cities today. One of the great distinctive features of these historical systems is the way in which they are superimposed on existing geography, transforming and extending it. This amplification of geography is closely linked to the management of water, roads and soil disturbance. From its very inception, it has been seen as a way to shape the metropolis of the future.

One cannot help but be struck by the way in which these landscapes were able to gradually integrate the upheavals brought about by growing industrial cities as well as changes in mobility and lifestyles. Today, we can appreciate the opportunity these landscape structures represent and once again draw inspiration from them.

They offer an effective model for organizing urban peripheries and disused areas. Their typology can be transposed, in the opposite direction, to provide the missing structure for contemporary urban sprawl. Geographical remnants, clusters of infrastructure, and industrial sites are all potential settings for such re-conquest.

Euralens Centralité and the Chain of Parks, mining basin, France, 2010

Our approach to the landscape in the mining basins of France and Belgium was inspired by this vision. The wastelands left by former mining operations, slag heaps and towpaths were transformed into a series of “places” and “links” to form vast chains of parks giving structure to existing communities as well as to their development through a process of re-composition.

The aim of the Euralens project was to take advantage of the opening of a branch of the Louvre Museum and a TGV station to revitalize the former mining region. The project called for creating a “central hub” for this geographical area of 400,000 inhabitants, centered on three municipalities — Lens, Liévin and Loos-en-Gohelle. This project was a continuation of the one begun when the mines ceased operations forty years earlier. Many of the sites had seen nature reintroduced and been transformed into recreational areas. But these sporadic initiatives resulted in a patchwork effect. Together with urban planner Christian de Portzampac, we were commissioned as landscape architects to imagine the redevelopment of this area. We championed landscape as a central means of triggering these major transformations, anticipating and initiating new living practices and approaches in the short term.

The last active mines, at 9-9 bis de Oignies, closed in December 1990. Most abandoned sites have been reclaimed by pioneer species of vegetation. These thousands of hectares of nature are now evolving separately from the city. Meanwhile, urbanization is continuing to fill in the gaps, sometimes agriculturally, between existing central areas. The expansion of low-density, dispersed housing developments is creating strong pressure on “empty” land. This tendency to fill them leads to a kind of saturation of these spaces, and the fabric becomes increasingly banal.

The first transformation was to change the way we look at these displaced spaces and lands. The scale and very nature of these areas call for a more “revelatory” rather than “compositional” approach, and the development of a landscape style that is as generous as it is “elementary”. Far beyond the generic and vague idea of “wasteland”, the extensive amounts of displaced soils left over from triumphant mining operations now represent real topographies, a new symbolic and physical horizon, and the concrete basis of a great ecological wealth.

As the 21st century begins, this territory, shaped by mining operations, can be viewed as an archipelago. Mining sites that have been abandoned for decades have left a network of voids, often reflecting former material transport networks. It would have been simpler — and some urban planners began to do so — to fill these voids with buildings. We preferred to see them as a potential network of connections and promenades which simply needed to be revealed. In order to make these transformations tangible, we needed to rearrange and prioritize them. A territory’s development cannot be homothetically extended or contracted. Creating a public space or an urban project on the scale of a neighborhood differs from working on a conurbation, and even more so from working on a vast territory. The physical cohesion sought is specific to each scale of intervention, and connections are necessary to ensure continuity.

Careful attention to the complex nature of coalfield landscapes and their particular geography is central to the transformation of this territory. Like the slag heaps, we view the abandoned mine towpaths (networks of dykes and embankments, built so that wagons laden with materials could move around and cross roads on bridges) as potential parks, with their abundance of both spontaneous and cultivated vegetation. They become a network of connections and promenades to be revealed, strengthened and completed so that they can form a whole, folding in existing public parks and facilities as well as potential new ones. Derelict infrastructure and industrial sites form a neo-system of parks: a series of connected places and paths that enhance the living environment and invite new ways of getting around, particularly favoring soft mobility.

This integrative development pervades even the deepest corners of the territory, reaching into housing developments, through their scattered gardens and along their paths, before being applied to the whole of the former mining basin. A new centrality emerges for all three communities. This structuring landscape links in with existing parks, public spaces, and facilities and supports increased density in these mining towns. The Chaîne des Parcs is not “simply” a “green” feature of an urban project. It is one of the key elements of an overall territorial project.

Our revised interpretation of mining geography has therefore focused on highlighting the voids that characterize the area and making them the basis of its transformation. This vision resulted in a distinctive structure: an interdependent, hierarchical archipelago linked together by a foundational landscape network. Today, this “Green Archipelago” seems quite obvious, and has a unifying meaning that makes it immediately adaptable, but which requires us to rethink the way we look at our industrial heritage.

La lisière, Paris-Saclay campus, Greater Paris, France, 2009-

In 2009, as part of a team including urban planners Floris Alkemade (FAA) and Xaveer de Geyter (XDGA), we won the international urban design competition for the Paris-Saclay project. The project’s aim was to expand and enhance this teaching and research site, making it a major hub in Greater Paris’s future development.

The Saclay plateau stretches across 5,000 hectares of highly fertile land above valleys it is linked to by wooded hillsides. The École Polytechnique was built on the Saclay Plateau in 1973, as were other large-scale projects, which were sometimes isolated and difficult to understand in this immense territory. Its scale was quite intimidating: we were asked to consider a perimeter of over 30 kilometers.

This large-scale project reflects many of today’s issues. The territory is fragmented, with both urban and agricultural areas juxtaposed in a way that makes them seem unaware of each other. Clearly, the composition of the buildings alone does not provide unity. The large buildings built by architects seem to float on this plateau, even though they are sometimes 200 to 300 meters long. A skyline that unites them and transcends their cumulative effect is needed. Greenery can provide this aspect to free-standing constructions and bring cohesion to the various parts of this archipelago.

We have opted to progressively manage urban development through its infrastructure, using Washington’s western expansion between 1900 and 1950 as a reference point. As it happens, the southern part of the science campus overlaps almost exactly with the Georgetown University district. We researched these similarities using Olmsted’s working documents: photos, drawings, cross-sections and time frames. Today, the trees have grown and the layout’s legibility is extraordinary. It welcomes today’s urbanization, giving it meaning, structure and quality of life. It therefore makes sense to propose projects that will be managed over a fifty-year period to create a landscape and an enhanced geography for the city of tomorrow.

The project calls for developing an “amplified geography”, in some cases complementing existing landscape features along the edges: the aim is to extend and thicken hillside woodlands, extending them into the plateau’s core. These green corridors accommodate a variety of transport infrastructure. Public spaces with multiple functions — ecological, recreational, productive — are thus created between the new neighborhoods and the large expanses of farmland. Extensive stormwater management systems, the restoration and expansion of natural environments, and even the management of soil left over from large-scale construction projects provide the opportunity to create this vast system. Taken as a whole, they form a framework for the landscape, the boundary, which ensures the relationship between city and countryside.

This boundary is made up of existing landscaped areas (Palaiseau National Forest, the Normandie and Vauhallan Woods) as well as new areas. It is, however, a composite of spatial entities of different sizes, functions and management practices. The choice of building density for the development of the urban campus allowed almost 180 hectares to be freed up for the creation of this landscape on the edge of the plateau’s protected agricultural and natural areas. This forms the boundary at the scale of the urban campus (Municipalities of Gif-Sur-Yvette, Orsay and Palaiseau). This boundary is not a dividing line that temporarily establishes a stable urban edge. It expands and enriches, becoming a place where two worlds that have long been pitted against each other — the city and the countryside — can be brought together. The combination of ecology and engineering is essential to the creation of this intermediate landscape. The boundary of the Moulon district (municipality of Gif-Sur-Yvette) is a showcase landscape for the campus as well as a public space able to enhance the relationship between the district’s streets and its country lanes. The network of trees provides both an element of cohesion and a valuable source of ecological continuity and varied habitats. The northern boundary of the École Polytechnique and Corbeville districts (in the Palaiseau and Orsay municipalities) is wooded. The district’s water management system occupies a significant part of its surface area: regulatory basins and wetlands are implemented according to precisely quantified needs to accommodate the district’s water.

The initial tangible achievements of all these major strategies offer a glimpse of how landscape design can be used to create systems and processes capable of producing certain conditions for the development, attractiveness, and livability of contemporary urban areas. The realization of the Euralens and Plateau de Saclay development strategies strengthens our conviction that landscape is at the heart of territorial challenges.

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APA

Michel Desvignes, Great Landscapes in Progress Euralens Centralité and the Chain of Parks and La Lisière de Saclay, Jan 2024,

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