A cross-border project between France and Switzerland, the CEVA Green Way has a major impact on the region. Combining a route for active transportation, public spaces and natural ecosystems, the Green Way is a large-scale experimental platform with significant landscape and ecological implications.
On the Swiss side, this cantonal project crosses five municipalities over nearly 3.5 km. ARFOLIA won the tender in 2009 for the landscaping of the green spaces and surrounding areas that make up the Green Way. After 10 years of landscaping studies and several planting campaigns, the project was completed in 2019.
Transforming an underground railway into a soft mobility route
The opportunity offered by putting the railway line underground allows for the release and development of surface areas for soft mobility and the creation of new areas with high environmental value.
Cyclists, pedestrians, and vegetation coexist on a narrow strip, varying from 15 to 50 meters wide. The asphalt cycle path is separated from the pedestrian zone by a drainage material to collect surface water. The surrounding areas, benefiting from sufficient soil, are dedicated to the restoration of specific environmental habitats and the replanting of tree cover.
The aim was to restore the pre-construction natural environments in certain areas and create new ones. We mapped the different zones along the entire route and selected species based on the project we wanted to develop. These choices then had to be validated by the various departments and stakeholders involved. Collaborating on this project as a multidisciplinary team resulted in significant environmental benefits.
Restoring large-scale landscape continuity
From the border to the Eaux-Vives station, the route of the Green Way is very linear. One of the challenges we identified was to break this linearity by connecting to transversal elements, existing urban pieces or landscape features that are landmarks on the scale of the wider landscape.
Different specific sections run along the Green Way, each with its own vegetation and substrates. This offers pedestrians and cyclists a variety of landscapes ranging from a very mineral xeric environment, to the wetland environment of the banks of the Seymaz, to a structured line of trees at the entrance to the Eaux-Vives station.
In addition to recreating specific biotopes, we also proposed potential connections with schools, cemeteries, and parks along the route. The Green Way thus becomes an integral part of the public space and connects to the existing urban fabric.
The key was to preserve a large-scale landscape continuity while offering occasional respites.
The importance of light in landscape architecture
Four priority ecological zones are located along the route. In these areas, as throughout the entire route, lighting was a key aspect of the project. The choice of public lighting had to be consistent across the different municipalities for aesthetic uniformity, but above all, it had to be carefully designed and controlled to take into account the local flora and fauna in order to avoid any nighttime disturbances. With directional LED lighting, specific color temperature, and intensity, external pressure is controlled. The use of motion detectors and twilight sensors limits the intensity to minimize disruption during the night while ensuring the safety of users.
The CEVA Green Way has become a landmark in the Geneva cantonal landscape
The Green Way is a landmark in the Geneva landscape, promoting alternative modes of transportation. The challenge of a project like this is successfully integrating vegetation into a very constrained environment. The tunnel carrying the railway line is directly below, which forces us to develop, question, and obtain approval from everyone involved for specific construction techniques. In some areas, we have activated nature through seeding and planting. In other sections, we have left the mineral surface free to natural regeneration. In the long term, vegetation will naturally reclaim the areas where it is meant to, and that's the whole point!
