Reconnecting the Agios Germanos River

The Agios Germanos River begins high in the peaks of Mount Varnous and flows through the Prespa basin before reaching Great Prespa Lake. Though only 23 km long, it is the largest and most dynamic river on the Greek side of the basin and lies entirely within a Natura 2000 site. Along its course, it passes through beech forests, riparian woodlands of willow, birch, ash, and poplar, before reaching young alder forests and reedbeds at its mouth. This rare freshwater ecosystem supports seven endemic fish species, including the Prespa trout (Salmo peristericus), and provides habitat for wildlife such as brown bears, European wildcats, roe deer, wild boar, and many bird species.

In its lower section, however, the river is fragmented by three fords and a deeply eroded area near its mouth to Great Prespa Lake. These barriers block sediment transport, disrupt the river’s natural dynamics, and prevent the upstream movement of endemic fish species. The erosion, worsened by decades of declining lake water levels, has created a drop over 2.5 metres high, functioning like a small waterfall. Together, these obstacles threaten the ecological integrity of the Agios Germanos River and the wider freshwater ecosystems of Prespa National Park.

Through this project, the Society for the Protection of Prespa is now carrying out the most technically demanding step in our continuous efforts on Prespa’s rivers: preliminary studies for the removal of these barriers. These studies are producing scientifically sound solutions for restoring the river’s continuity, while also considering the access needs of local communities.

By opening almost 5 km of upstream habitat and contributing to reconnecting more than 60 km of waterways in the basin, this project adds a vital dimension to our wider efforts on Prespa’s rivers and streams (Prespa’s Green and Blue LifeLines, Prefeasibility study on rehabilitation of Agios Germanos River). This project lays the essential preliminary groundwork for future barrier removal, providing scientifically sound solutions that will guide the more detailed technical work still required before implementation. It marks a decisive step towards securing the survival of endemic fish, restoring riparian habitats, and safeguarding the natural lifelines of the Prespa basin for generations to come.

This project is supported by the European Open Rivers Programme – a grant-giving organisation dedicated to restoring rivers.