A natural Glatt –a win for biodiversity and recreation

The area given to the Glatt will almost double, compared to the area it occupies today. Within this space, the Glatt will be allowed to meander freely. Essentially, it will be freed from its existing corset and can flow dynamically. Due to processes such as erosion and sedimentation, the river loops can shift over time.  
  
Prior to the official start of construction and the creation of the near-natural river course, felling and clearing work is required along the Glatt. The branches, trunks and rootstocks ultimately structure the new water course. They become a habitat for flora and fauna and serve as shade cover, spawning grounds or refuge area. The cleared areas will be re-vegetated with native plant species at a later stage of the project.  

After the soil has been carefully removed, the riverbed is excavated, and the near-natural course is created. Curves and bends are modelled into the new course of the river. Finally, the water is diverted into the newly created channel. The natural flow movement now contributes to the formation of meanders, which are naturally formed river loops. 

The revitalisation will give the river more structure and diversity. Riverbank vegetation and alternating shallow and steep riverbank zones are an ideal habitat for fish, amphibians and insects. As part of the project, reedbeds, wetlands and embankments, small ponds and floodplain areas will also be created.  

The reed meadows, which cover around 5 hectares, are biotopes that are considered to have a high biodiversity and are particularly valuable from a nature conservation perspective. A reed meadow is an extensively managed wet meadow. It includes several habitat types such as small sedge or whistling grass meadows. The future reed meadows are located in the Eichhof and Loo areas. To create these meadows, a layer of soil will be removed and then the raw soil will be directly revegetated using cuttings from suitable reed meadows in the vicinity of the airport.  

This project promotes 100 rare plant species. The 950 newly planted trees include ash, European white birch, black alder, pedunculate oak, white willow and almond willow. Among the target species are the lesser purple emperor butterfly, the kingfisher, the tree frog, the lesser marbled fritillary butterfly, mouse garlic and the Siberian iris.

The enlarged river area and locally raised banks increase the protection of neighbouring areas against flooding. By creating natural floodplain landscapes, the river can also better absorb flood waves. Both contribute to improved flood protection.  

As part of the project, flood protection measures will be implemented on site. These consist primarily of raising the terrain of the riverbanks, which in some places will be done at the same time as construction of the new paths. The minimum width of the river area will be 50 meters. This width is sufficient to cope with a flood that can statistically occur once every 100 years (HQ100 event). The widening of the river area and creation of a natural floodplain landscape are expected to prevent major flood damage once the project has been completed. However, minor flooding may still occur in rare cases in some agricultural areas and at the lower levels of the rest areas – so-called HQ30 events, which occur on a statistical average of once every 30 years.

The new course of the river will be made more accessible by gently extending the path network. In the Tolwäng and Fromatt areas, attractive picnic zones are being created, with direct access to the water.  
  
The Tolwäng and Fromatt rest areas will offer similar recreational features. They will have an extensive surface that blends harmoniously into the surroundings thanks to natural aging of the materials used and greenery. Steps will be created at the water's edge to provide comfortable seating and, depending on the water level, direct access to the Glatt. There will also be seating and simple barbecue areas. The recreational areas can be spotted from afar by the striking groups of trees consisting of oaks, white willows, almond willows and ash trees, which provide shade and add to the special character of these areas. 

One of the newly created ponds will be made accessible to the public by a viewing platform. This will allow visitors to experience the diversity of species in the pond and the surrounding landscape. 

The paths are laid out in such a way that different activities can take place without any trouble. The revitalised river section can also be explored as a circular route via existing bridges. At multiple locations, the footpath offers beautiful views of the Glatt. The cycle and inline skating routes run along the right bank. The existing inline skating route south of the wooden bridge near the Tolwäng recreational area will be merged with the existing cycle path. The inline skating route along the airport fence with its many sharp turns and poor visibility will be removed.