PAP 61: Sobriety, a lesson in life and a counterweight to the devastation of the world

For an economy of embankments and excavations in development projects 1.

Alain Freytet, October 2022

Le Collectif Paysages de l’Après-Pétrole (PAP)

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Landscape architects readily display their support for the cause of ecological and energy transition. This commitment inspires them when they draw up planning documents, landscape charters and landscape plans. What about when they implement their actual development projects? The approach to a new project that will transform space and nature opens up a space for creation that cannot easily be accommodated by constraints, even if they are virtuous. Setting rules to contain the environmental impacts and energy expenditure of the project can appear to be a brake on creativity.

Leaving spaces undeveloped, planning them without intervention, can seem like resignation. Reducing or forbidding planting is perhaps to question the profession of landscape gardener, so often associated with gardening. In the same way, if we want to respect short and low energy consumption channels, we will have to proscribe certain attractive materials or manufactured objects. More centrally, would restricting the amount of excavation and fill that would reconfigure the shape of a site prohibit its reinvention? We have decided that these virtuous constraints, which are suitable for ensuring the ecological transition, can, on the contrary, build a more sober, more harmonious site project, which is likely to deeply touch the hearts of those who come to walk there, contemplate the surroundings and recharge their batteries. This is the direction in which we have committed ourselves with the Conservatoire du littoral, throughout a collaboration that has lasted for many years. Some landscape architects still consider excavation and embankment operations as a founding act of the project and its very condition. This practice was common during the thirty glorious years, when the dramatic need for ecological transition was not yet apparent, when the energy cost of a project was not important, when spending tons of carbon to move tons of earth was not an issue. Projects that define fill as the major and necessary design tool belong to the past. They have their own logic and aesthetics, are inspired by great historical projects such as the park of Versailles or the terrace of Saint-Germain, and prevailed in the 18th and 19th centuries in English parks ².

Excavation and embankment operations require the use of machines to dig, level surfaces, load and transport. These machines are oil-powered and require a great deal of energy. This expense is multiplied when a site is not in « cut and fill balance » and material has to be imported or exported, and often both. Lorries on the roads, the opening of quarries for the extraction of materials, and the dumping of waste on sites that have been condemned to receive waste consume energy and modify the space, often affecting the natural environment and imposing ever larger roads, quarries and landfill sites. While these impacts are unavoidable, their size and significance can be minimised by soberly shaping them, especially when it comes to the development of areas that have not yet been disturbed by human installations. In this case, a different attitude is required in relation to the site’s data, especially its soil and relief.

When fill is brought in or excavated, the substrate is impacted

The excavation is a tearing away of the soil, an erasing of the relief. The surface of the earth is scratched, the relief is erased, the soil is removed. Backfilling, on the other hand, is a smothering, the crushing of an existing substrate by an exogenous input. By modifying the soil and the relief, cuttings and fills alter these two primordial elements of the landscape. Such an intrusion is disruptive and often destroys a heritage whose loss will be irreparable. Conversely, attention to the site and its substratum makes these two elements infinitely precious. This look at the earth’s surface is for us the first foundation of the landscape project. We now know that the soil is a precious medium because it is rare, both in a natural space and in the city or countryside. Every day we discover more complexity and richness in this subtle mixture of living organisms and physico-chemical compounds, intimately linked to the place on which it has developed for often thousands of years. Soil contributes to biodiversity and participates in the balance of ecosystems. This living substrate contains an unsuspected memory that DNA fragments now make it possible to explore. Its seed bank, its cohort of insects and micro-organisms are an irreplaceable value for the future. This is why, when soil is transported from one place to another as if it were a homogeneous material over the whole of a territory, we forget the very long processes that have put it in place and are intimately linked to its site, its climate, its bedrock, its flora and fauna as well as to its human history. The soil is therefore a value that landscape projects should take into account, ensure and respect. The objective of a landscape project attentive to the soil is to touch it as little as possible, to transform it as little as possible by avoiding the use of fertilizers or pesticides. For many developers, the site is often considered to be a blank page that calls for free improvisation. The soil remains a material that can be moved, subtracted or added to as one would with raw materials. A strange attitude in certain layouts consists of enclosing small volumes of soil in planters to grow plants, imagining that they can ensure absolute control. Nature is thus kept under perfusion, the plant survives by the power and goodwill of its manager. In many cases, these planters could be replaced by planting hardy plants in the ground, which would not require watering or fertiliser. Green walls, levitating plantings and slab gardens are all forms of façade greening that have little to do with the landscape. In order to improve the quality of life and breathing temperature, the renaturation of cities requires us to think about the depth of the soil and to plan for the autonomy of the plants that will develop there. If we want to take into account the change of era and know how to ensure it, we must abandon the images of colourful exotic gardens full of pesticides, fertilisers and watering and reconcile ourselves with plant environments close to those of natural environments. It is in this respect that the soft landscaping carried out on sites that are still little impacted by man can become leads and suggestions for visitors, elected officials and project managers. By coming to discover and walk around them, they will become familiar with a completely different conception of the possible relationship between man and the earth, an attitude that distances itself from proud demiurgy to cultivate respect and contemplative attention.

As a witness to a very long planetary history, the relief projects us into the immense scales of the earth’s time and space. Relief tells the story of sunken worlds, long before the appearance of man. By distinguishing between the major families of sedimentary, crystalline, volcanic and metamorphic rocks, geological maps link the existing landscapes and their landforms to the specific evolution of their substrate. The major cycles of erosion, transport and accumulation of loose and solid rocks have followed one another. The relief can be read as a permanent movement whose slow and imperceptible evolution continually transforms the rocky mantle and its plant populations, sculpted as it is by geomorphological agents such as river water, diffuse water, wind, ice and gravity. These forces leave traces that orient and guide our gaze and our attitude towards a landscape. For those who know how to read them, they come to be inscribed in our bodies through a kind of muscular sympathy. I propose to play « geological mimes » to my students at the École nationale supérieure de paysage de Versailles so that, by embodying them with their bodies, they appropriate the energies that have created the movements of the relief. These mime sessions allow us to grasp the founding characteristics of a site and to construct the landscape project entrusted to us as accurately as possible. By using the body and gestures, the geological and geomorphological dynamics are inscribed in the memory and are more easily mobilised in the landscape project process.

The very long history of human settlement has scarified the surface of the earth by scratching, notching and shaping a soil that retains the memory of its successive uses and the settlements that may have been established there. Like a palimpsest, these traces constitute a memory of the events that took place there. The recent LIDAR surveys use a remote sensing method similar to radar, which allows a very fine visualisation of these micro-reliefs using infrared light pulses. Which Gallic farmhouse lived here? Which fortress, which hermitage? These surveys enrich our perception of the ground surface and make us much more cautious when a project is planned to disturb it. This interest in the relief and the micro-reliefs allows our project choices to be part of the history of the site, in full awareness of the processes that gave birth to it. Today there is a danger. There is talk of loss of biodiversity. We could also talk about the loss of geodiversity. In the age of oil, machines of titanic power have appeared. They can move large quantities of material and erase these traces of the Earth easily and quickly. Engineers in charge of major works have a culture of excavation and embankment that prevails in particular when creating transport infrastructures. The objective of speeding up travel, as defined by computer calculators, imposes irremediable upheavals. Companies equipped with ever larger machines to meet the demands of their clients are less and less able to carry out the delicate and economical work that they never consider. The search for straight lines and computer formatting have given rise to an aesthetic of a regular slope. For many public works companies, a job well done consists of erecting taut slopes. The search for more natural shapes in the continuity of the surrounding relief, the emergence of outcrops or the creation of small depressions that are requested in certain projects are often confronted with a culture of cut and fill that is seen as a conquest of nature and the relief.

These traces are important in the case of a historical site that is visited precisely for this reason, such as Gergovie, where the remains of a Gallic town are buried, or Cape Fréhel, where discreet modelling carried out during the last war is inscribed. In his book « L’identité de la France », Fernand Braudel says that he appreciates the small secondary roads which « speak the precise language of the relief ». They weave their way through the landscape like paths, highlighting the landscape structures and allowing us to appreciate their subtleties. In contrast, the 19th and 20th centuries saw an increase in the number of large, wide, straight lines that established an unprecedented model of mobility: the conquest of space through movement. Inspired by the finesse of these old routes, it is possible today, even in the case of major projects such as a motorway or a high-speed train line, to work on the shape of the embankments and cuttings to better connect them to the surrounding relief. On the crossing of the A75 in the Lozère department, the work of Claude Chazelle, landscape designer, is exemplary in this respect ³.

It is regrettable that the lessons learned from this work do not inspire current road and rail projects, however modest or ambitious they may be.

The Cap Fréhel project, carried out for the Conservatoire du littoral, addresses these important components of the project on its own scale. It was recently awarded the Grand Prix National du Paysage. It owes much of its interest and logic to the way in which we have treated the soil and the relief. Cap Fréhel, in Brittany, is a rocky point with high cliffs of pink sandstone jutting out into the sea. At the end of one of the largest Atlantic moors stands a monumental lighthouse. As in many tourist sites, the attraction of such a site has called for heavy and invasive developments that have damaged its very value: a restaurant on the edge of the cliffs, a large car park at the foot of the lighthouse, a trampled moor, scattered street furniture… Very early on, in an attempt to curb these excesses, the site was listed. Today, it has the « Grand Site de France » label. The Conservatoire du Littoral acquired the restaurant in 2012 and the land around the lighthouse a little later. This was followed by the elaboration of a scheme of landscape intentions ⁴ and the drawing of sketches which spatialise and express the main principles of the project: to reinforce the integrity and power of the moor, to give meaning to the lighthouse, to rediscover the spirit of the cape in order to determine the course of the paths and to give them a sober and discreet treatment.

Once the scale of the site itself has been restored, its riches will be made visible from two interpretation points where information is concentrated, leaving the rest of the site with nothing to read. The reception system will be placed on the scale of the Grand Site, i.e. as a prelude to a discovery which is made by a time of access on foot. As in a dramaturgy, this step backwards provides so many stages that graduate the intensity of the discovery. The aim is to rediscover the naturalness of the site, which carries a message for today, by recreating the conditions for a powerful poetic vision that makes the visit a moment of inspiration and renewal. On this shared basis, the construction phase could start in 2017.

The structure of the site and its substratum: observing the relief and its genesis

The shape of Cap Fréhel is marked by large undulations linked to a very particular geology. Rising lava in the parallel fractures of the sandstone mantle has given rise to veins of a rock called dolerite. These harder seams armour the « rillons », small blunt ridges colonised by dry heathland, leaving the hollows to wet heathland. Dolerite is more sensitive to marine erosion than red sandstone. Narrow indentations were then formed, rectilinear crevasses which cut into the great mass of cliffs of Cap Fréhel all around the site, giving it its massive strangeness and fascinating singularity. The direction of these seams on the surface of the moor, hardly perceptible at first sight, constitutes a landscape structure which will order the project both to orientate the new car park and to remodel the relief of the vast parking platform previously levelled around the lighthouse, once it has been removed.

Access road returns to natural ground to guide visitors

One of the major challenges of this transformation was to cut off the previous traffic route leading directly to the lighthouse. By creating a chicane that would naturally lead motorists to the new parking lot, the straight road to the lighthouse would become secondary. The proposed solution was to remove the tarmac from the road and return it to a natural surface, adding some of the soil taken from the area where we extended the car park. On this newly created small relief, we completed the spontaneous vegetation provided by the seed bank constituted by the soil by transplanting and cutting brambles and willows. A year after the work was done, we forget that the road went straight. One is naturally led towards the new car park without any frustration at not being able to reach the goal at full speed, as when one could drive to the end. This sober treatment reduces incivilities.

The shape of the new car park returns to the ground and is guided by the lines of the natural relief. The only parking area on the site is now nestled in a hollow in the relief, which makes it hardly visible from the coastal path or from the various paths on the site. The pavements fit into the natural structure of the relief by taking the general direction of the dolerite veins. This new orientation of the spans makes them more discreet, seen from the top of the lighthouse. To minimise the embankments that follow the relief, the different parking pockets are slightly offset. The ground of the parking spaces remains natural and filtering. Willow branches taken from the surrounding trees were cut into the ditches that collect runoff water. The protection of these areas left to natural vegetation is ensured by small low ganivelles.

A principle: aiming for a balance of cut and fill on the site

On this Cap Fréhel project, as on others carried out with the Conservatoire du Littoral, the search for such a balance is a basic rule for reducing the ecological and energy costs of the development. This objective presupposes good coordination between earth movements and demolition products. The thickness and quality of the materials are always uncertain, despite soundings and samples. This uncertainty requires constant adaptation of the site and collaboration with the companies.

Recovering the ground and the relief around the lighthouse

Before the work, a large asphalt parking area encircled the foot of the lighthouse. The monument and its ground were choked with cars. The decision was taken to remove this parking area and to leave only a pocket of parking on the site, offset by 150 m. In February 2019, the tarmac surface of this car park was removed and the ground breathed again, while the only asphalt surfaces retained ensured traffic flow. On this tarmac-free surface, the heathland will return naturally, without planting, fertilising or watering. No herbaceous sowing is carried out in order to avoid any genetic pollution of local plants. The organic matter brought in comes from the site. The soil and its seed bank, its cohort of insects and micro-organisms are reconstituted. In May 2022, the heathland will come back with a vengeance. Depending on the rising damp, the quality of the soil and the input of plant matter, the plants have found a distribution that gives the project an aspect of creative uncertainty synonymous with the greatest biodiversity. The challenge of « doing little to do better » has been won. Not planting and letting things happen by subtly accompanying the spontaneous colonisation, this action has paid off.

A regular platform had been established for parking. The aim is to remove the artificial levelling of this earthwork. By taking up the orientations of the wrinkles and depressions linked to the geology of the cape, a vast undulation is shaped. It provides a view of the sea from the access road to the lighthouse.

Preserving the old soils

Even if they do not have the qualities of new floors, the old coverings have been kept. This choice allows for financial and ecological savings. On the terrace of the Foghorn, the floor, with its stone and concrete slabs, has been preserved despite its unevenness. The holes are filled with coarse aggregate cement. It tells the story of the various buildings that have followed. On the former parking lot at the foot of the lighthouse, the asphalt pavement has been cut out with a grinder in order to keep the paths regular. The design of the paths seems to skim the moor and emphasises the symmetrical composition of the lighthouse. A trained eye can see the marks of the old parking spaces on the remaining asphalt.

Reuse of demolition products

The demolition of the many small concrete buildings scattered around the headland produced a lot of inert material. Some of this spoil was used to fill in an old pathway cut into the rock slab. This was removed because it opened up a direct and abrupt arrival at the end of Cap Fréhel, without offering any views of the sea along the way. On top of this backfill, soil from depressions in the moor is spread. In place of the old road cut, a natural relief profile is found. The old path is now forgotten in favour of a path which, passing over the natural sandstone outcrop, does not lose sight of the horizon. The paths established on the regular lines of the sandstone give contact with the base and a surprising comfort of walking.

Recomposing the design of a plausible natural outcrop

To heal the hollow path filled in by the backfill from the demolitions, large pink sandstone stones are laid out like a rocky outcrop punctuated by the sequence of sedimentary strata. A small smooth wire fixed at a height of 30cm prevents trampling on this area where the vegetation is allowed to return naturally. Close to a path frequented by nearly a million visitors a year, the heather heath can be recomposed. While trampling causes the rock to bloom and prevents the vegetation from expressing itself, such a device shows that it is possible, with a minimum of means, to make the preservation of biodiversity compatible with the use of a large public.

The use of pink sandstone, the site’s stone, in the new facilities

Stone, a raw and natural material, tells the story of the Earth: every rock has a strength and a power of evocation, unlike other transformed materials such as metal, glass, concrete or plastic, whose method of manufacture has a significant ecological cost. It is difficult to date a stone structure. We have chosen this timelessness to give a coherence and a particular density to the installations proposed on the prestigious site of Cap Fréhel. Stone is a local material and is not wasted. By taking care of the extraction site in a nearby quarry and the artisanal shaping of the stone, this local resource is very sober. The pavements and steps were built in dry stone. This technique, which is exemplary from an economic and ecological point of view, requires neither water nor concrete. Adjacent to the buildings, at the foot of the old lighthouse, low walls built of sandstone form an enclosure that follows the profile of traditional walls. Inside, a low bench wall allows walkers to sit in the shelter, without the need for urban benches that would break the simplicity and sobriety of the design. By looking at the surface of the Earth, seeking to move its soil as little as possible or transform its relief, we have found a thread that runs through the ages to the origins of time. Occupying a modest and silent present, such a project revives a posture where man is small in the face of the scale of the world. In a land that has been transformed, even altered and devastated, a visit to Cap Fréhel awakens the child’s gaze on the threshold of a splendid immensity that he or she does not control. Visiting natural sites is today a necessary rite, capable of re-educating our attitudes of power and blind omnipotence.

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