On Tuesday 11 August 2026, Luxembourg nature conservation organisation natur&ëmwelt announced its opposition to the planned €390 million Alzingen bypass, citing concerns over its potential impact on biodiversity, protected habitats and sustainable mobility.
The organisation issued its opinion on draft law No. 8754, which aims to authorise the government to finance the construction of the Alzingen bypass.
According to natur&ëmwelt, the planned bypass would pass through the heart of the "Upper Alzette Valley" Natura 2000 site, negatively affecting this important bird protection area and its wider ecosystem. The road would also cross forests south of Luxembourg City which the organisation described as “highly threatened”.
The organisation highlighted that biodiversity there serves as a feeding area and habitat for numerous protected animal and plant species. Among these is the white stork, which is regularly observed during migration in groups exceeding 60 individuals and during the summer. Attempts at nest building have also been documented. According to natur&ëmwelt, the species currently nests in Luxembourg only in the Alzette Valley, where one breeding pair has been recorded.
The organisation also pointed to the presence of the great egret, which regularly winters in the area's wet and flooded meadows. During periods of flooding, the Alzette plain also serves as a stopover for bird species including the common crane, ruff, northern lapwing and European golden plover.
natur&ëmwelt noted that the area also retains ecological potential for the corncrake, despite the species no longer being considered a breeding bird in Luxembourg. It added that intensive management of the area's meadows, including mowing from early May, already affects the ability of certain bird species to complete their reproductive cycle.
The organisation argued that restoring habitats and appropriately managing wet meadows are essential to support these species, while the construction of a new road and the resulting increase in traffic would run counter to these objectives.
It further highlighted the role of the valley's meadows and wetlands in regulating water levels, preventing floods, recharging groundwater and supporting agriculture. According to natur&ëmwelt, soil sealing and habitat fragmentation caused by the project could result in biodiversity loss and weaken the ecosystem's resilience to climate change.
Beyond its environmental concerns, natur&ëmwelt described the bypass as an "outdated response" to mobility challenges. It argued that increasing road capacity would only temporarily ease congestion before generating additional traffic, and called for public investment to prioritise public transport, cycling infrastructure and measures aimed at reducing car traffic towards Luxembourg City.
The organisation also questioned the €390 million investment in the context of constrained public finances, arguing that such resources should instead support projects including public transport, nature restoration and climate change adaptation.
natur&ëmwelt further expressed concern that the project could affect the protected area while compensatory measures linked to the new Luxembourg-Bettembourg railway line have yet to be implemented. It called on lawmakers to ensure that appropriate compensatory measures are put in place before any works begin within the Natura 2000 site and said it reserved the right to take further steps to oppose the project.
The organisation also raised concerns over what it described as “a lack of transparency” from the authorities. It stated that questions raised during meetings, through correspondence and as part of the public consultation had remained unanswered, as had a letter it sent in July 2025.
