Phase 2 of Pétrusse Restoration Project to Cost €15m

On Monday 10 February 2025, the City of Luxembourg (Ville de Luxembourg - VdL) in collaboration with the Ministry of the Environment, Climate and Biodiversity, presented the second phase of the work that will be carried out as part of the ecological redevelopment of the Pétrusse Valley, at a press conference held at the "Bierger-Center" (citizen service centre) in Luxembourg-Ville. 

The work is scheduled to begin in spring 2025 for a duration of two and a half years.

In a statement released by the City of Luxembourg, Mayor Lydie Polfer explained that “the renaturation of the Pétrusse Valley represents an exceptional project for the City of Luxembourg, aimed at enriching our environment while improving the quality of life of citizens. This ambitious project transforms the valley into a veritable green lung in the heart of the city, offering those who cross the area between Place St Ulric and the Bourbon lock - already renatured during the first phase of the ecological redevelopment of the Pétrusse valley - an increasingly pleasant experience. With the second phase of the work, these beneficial transformations will extend further towards the Hollerich district. Although work is necessary, the teams of the City of Luxembourg are doing everything possible to minimise the inconvenience and guarantee the full opening of the park from the start of the 2027 school year, for the enjoyment of all”.

The statement added that Luxembourg’s Minister of the Environment, Climate and Biodiversity, Serge Wilmes, underlined “the benefits of renaturation are obvious in several respects: the undeniable visual improvements are the same with regard to the ecological improvements in favour of the fauna and flora in the watercourse as well as on the banks. This positive measure for fish, butterflies and other living organisms also contributes to the protection of local residents by reducing the risk of flooding. Renaturations are therefore a perfect measure to adapt to the growing challenges of climate change, while contributing to improving biodiversity, water quality and increasing the quality of life of our citizens."

The statement confirmed that results from the first phase of development, carried out between 2020 and 2024, are largely positive. The Pétrusse river is no longer enclosed in an artificial concrete bed, but can meander freely and has regained river vegetation along its banks. Vegetation has quickly established itself around the watercourse and will continue to grow in order to create habitats for many animals and plants. The flow of water is slower and more natural, thus reducing the risk of flooding.

Phase 2: from the old Bourbon lock to Rue d’Anvers

The second phase of the project consists of the renaturation of the Pétrusse valley and the redesign of the park on the section between the old Bourbon lock (end of the first construction phase) and Rue d’Anvers. 

According to the VdL statement, the overall project consists of several sub-projects, some of which can be carried out independently of each other and some of which are spatially dependent and require complex construction processes. These works include the redesign of the landscape architecture and the replanting of the direct aquatic environment and the adjacent park, the renaturation of the riverbed and the direct water environment, the redefinition of the infrastructures and engineering structures.

• Ecosystem restoration: The main objective of the project is to restore the Pétrusse valley’s degraded and artificial ecosystems and to return it to a more natural state. In order to achieve this, some trees are due to be removed to ensure better expansion of biotopes and provide a lasting habitat for many animal and plant species. This work is planned to start on Monday 17 February 2025 and last for around ten days. During the felling, temporary diversions for park users will be set up from time to time. The VdL Traffic Department will install suitable diversion signs. At least 56 new trees will be planted and significant trees protected.

• Renaturation of the watercourse: As in Phase One, the concrete bed of the Pétrusse will be removed in order to recreate a natural morphology of the watercourse. The bottom of the watercourse will be developed with natural stones and the banks will be developed in order to create natural habitats for fauna and flora. The planting of a riparian forest and the succession of plants on the banks will allow the creation of an ecological corridor. This is expected to result in a more natural flow of water and a slowing of the speed of flow, which will lead to a reduction in the risk of flooding.

• Multi-sports field: Phase Two also includes the installation of a new multifunctional sports field. To achieve this, the current multi-sports field will be completely dismantled and the equipment that is still in good condition will be reused in the construction of the new field. The new field will have the same dimensions as the current one (13.0 x 25 x 5 metres) and will also be covered with a net. Once the construction of the field is complete, five new installations of fitness equipment will be put in place.

• Construction of an underground relief pipeline: To protect a private house located in the Pétrusse Valley Park, an underground relief pipeline will be built along the watercourse on a clearly defined section. This pipeline will ensure the safe flow of excess stream water and prevent the excess water from causing damage to private property.

In addition to the major projects mentioned above, the following interventions are also planned:
• the installation of stands and balconies at various locations on the banks of the Pétrusse;
• the renewal of the vehicular paths (4 metres wide) and non-vehicular paths (2 to 3 metres wide);
• the development of rest and leisure areas along the watercourse, using the same design for street furniture as for the already renatured part of the Pétrusse valley, in order to achieve fluidity and optical coherence;
• the redefinition of the engineering structures including four new bridges (one vehicular structure and three for pedestrians) replacing the existing structures.

During the second phase of the project, the paths along the bed of the Pétrusse will be inaccessible to pedestrians and cyclists. To accommodate cyclists between the Ville-Haute and the Hollerich district, a cycle path in the opposite direction will be set up on Rue de la Semois. This will result  in a  one-way system for motorised traffic in the downward direction. Appropriate signage will be put in place to provide information on detours.

The budget estimate for Phase 2 of  this land restoration project amounts to €14,991,055.56 including tax. The financing is provided by the City of Luxembourg and the Water Management Fund of the Ministry of the Environment, Climate and Biodiversity. The European Investment Bank (EIB) is also associated with the financing of the project through the Blue Natural Capital Financing Facility.

HOM