Vrbovo Dam, Slovenia

Introduction

The Reka River in Slovenia originates from the Snežnik plateau and flows for about 55 km on the surface. The river, meandering through a complex karst landscape, has carved the world-famous Škocjan Caves Park, which is also a UNESCO World Heritage site.

As the river enters the limestone Karst, it deepens its riverbed through erosion and corrosion by dissolving the limestone. This has created the unique natural phenomenon of the Škocjan Caves, which are protected at national, continental, and global levels. The area was designated as a Regional Park in 1996, and all natural values in the park are of national importance. The entire protected area is also part of the European Natura 2000 network.

The biodiversity of the caves, which are home to the fascinating and endemic olm (an aquatic salamander), is under increased pressure due to numerous barriers on the Reka that alter the natural flow and dynamics of the river, and intensify pollution.

The Vrbovo Dam is an insurmountable obstacle for migrating freshwater species, separating animal populations in the river. Removing the dam will open up 8km of valuable habitat for the marble trout and stone crayfish and improve habitats for other aquatic and terrestrial species. The forests along the Reka are a critical source of food and water and a home to many animal species, including brown bears and grey wolves, which are strictly protected under the EU Habitats Directive.

Project context and opportunity

The Vrbovo Dam has caused the settling of sediments such as gravel and stones, resulting in changes to downstream geomorphology and habitat, including higher flow velocity, depth, and lateral erosion in the riverbed below the dam. Removing the dam is essential to improving the ecological status of the Reka River, which currently has a medium WFD ecological status.

There are approximately 30 obsolete dams on Reka. The removal of the Vrbovo dam will open up 8km of river, allowing aquatic animals to migrate within the river system and creating more spawning habitats for fish species. Removing the dam will also improve flood safety, river morphology, and connectivity.

Removing the barrier will have numerous benefits for key species, improve the overall well-being of local communities, and create a potential for nature-positive recreational activities. The area will become more appealing once the dam is removed, and improving fish populations will boost sport fishing. Restoration of the river will also make it possible to engage in activities such as hiking and tourism.

The project will strengthen cooperation with local communities, increase public awareness of the benefits of dam removal, and facilitate knowledge sharing with other protected area authorities in Slovenia. The removal of the Vrbovo will be a showcase for the Reka River catchment and will drive further removals along the river and beyond.

Project aims

To achieve the project aims, the project will take a vital step forward in restoring one of Europe’s most beautiful sprout rivers, the Reka River. The goals of the project are:

• Dam removal.
• Providing benefits for key species: The biodiversity of the river and the caves is under increased pressure due to numerous barriers on the Reka River that intensify pollution. Removing the Vrbovo dam will open up valuable habitat for the marble trout, stone crayfish, and other aquatic and terrestrial species. There are also forests along the Reka River that are home to many species of animals, including the brown bear, a strictly protected species under the EU Habitats Directive, for which the Reka River is a critical source of food and water.
• Increasing the overall well-being of local communities and creating potential for developing nature-positive recreational activities. To scale its impacts, the project will strengthen cooperation and knowledge sharing with local angling societies, communities, decision-makers, and NGOs.
• Improving flood safety, river morphology, and connectivity: The Reka River currently has a medium WFD ecological status. Dam removal will be used as a showcase for the Reka River catchment and as a driver of further removals along the river and beyond.