The project will identify, assess and prioritise river barriers across the Bulgarian part of the Struma River catchment and carry out ecological, technical and legal feasibility assessments of selected high-priority barriers to prepare the ground for their future removal and the restoration of river connectivity.
The project focuses on the Bulgarian part of the Struma River catchment downstream of the Pchelina Dam, covering approximately 7,000 km² and around 800 km of rivers. It includes the main course of the Struma River to the Greek border and 14 key tributaries that are important for fish migration.
Located in southwestern Bulgaria at the crossroads of Mediterranean and Continental climatic influences, the Struma valley is recognised as a major biodiversity hotspot. The river forms an important ecological corridor connecting some of the highest mountain ranges in the Balkans with the Aegean Sea. Its diverse river habitats support numerous rare and endemic species, particularly fish and other aquatic fauna, while the wider catchment is also important for rafting, angling, hiking, viticulture, and fruit and vegetable production.
| Project status | Live |
|---|---|
| Project type | Barrier identification and prioritisation |
| Country | Bulgaria |
| River | Struma River |
| Focal species | Vardar nase (Chondrostoma vardarense), Struma barbel (Barbus strumicae), Dark vimba (Vimba melanops), Struma spined loach (Cobitis strumicae), Aegean chub (Squalius orphaeus), Struma stone loach (Oxynoemacheilus bureschi), Struma spirlin (Alburnoides strymonicus), Macedonian trout (Salmo macedonicus), Struma minnow (Phoxinus strymonicus), Aegean gudgeon (Gobio bulgaricus), Stone crayfish (Austropotamobius torrentium), Noble crayfish (Astacus astacus) and Thick-shelled river mussel (Unio crassus) |
| Organisation | Bulgarian Society for the Protection of Birds (BirdLife Bulgaria) |
| Website | bspb.org |
Despite its high ecological value, the Struma River catchment is heavily fragmented by numerous artificial barriers. Official records identify only 14 barriers, while preliminary assessments suggest that more than 300 structures may occur within the project area, revealing a major information gap. Many of these barriers are likely obsolete or no longer essential, but their ownership, legal status, ecological impact and technical feasibility for removal remain poorly understood.
At present, the West Aegean Basin Directorate is the only river basin authority in Bulgaria where dam removal activities have not been implemented. The project therefore provides an important opportunity to establish a comprehensive barrier inventory, identify and prioritise viable removal candidates, and develop the ecological, legal and technical evidence needed to prepare future barrier removal projects and restore river connectivity in the Struma catchment.
The overall goal of the project is to create the foundation for future river connectivity restoration in the Struma River catchment by identifying and preparing viable barrier removal projects.
The project team will establish a comprehensive inventory of barriers across approximately 800 km of rivers and prioritise them according to ecological significance and removal feasibility. Fifteen shortlisted barriers will undergo legal and ownership checks, while seven will be assessed in greater ecological detail, with fish as the primary focus and hydromorphology and macrozoobenthos as supporting indicators. For two of the most promising barriers, conceptual technical demolition designs and cost estimates will be prepared. Stakeholder consultations will help clarify potential concerns and administrative pathways. The expected outcome is a clear pipeline of feasible removal projects, with the ambition to achieve up to three removals within 3-5 years and up to ten within 10 years.
Funded by
