Rivers along the Cantabrian coast are threatened by fragmentation. Obstacles interrupting the continuity of the rivers have accumulated over the years to the extent that these obstacles can be found almost every kilometre stretch of the rivers. Moreover, they run for some distances (in the order of tens of kilometres). As a result, the river ecosystems have been altered and the range of the most sensitive species (semi-aquatic mammals and fish) have been reduced or fragmented. Together with genetic isolation and other associated impacts, such fragmentation jeopardises the ecosystems’ ability to recover from or withstand other pressures.

River obstacles are therefore extremely relevant to the management of Cantabrian Natura 2000 sites and are the main focus of River Basin Management Plans. These obstacles have also been the main focus of several public authorities responsible for river management in both the Basque Country and Navarra. Conservation efforts in both territories are combined with recent projects to increase cooperation among regions. As a result, the scope of the LIFE project includes two shared river basins: the Bidasoa and Oria basins.

Building on previous studies, the LIFE IrekiBAI project aims to improve the conservation status of river habitats and species listed in the Habitats Directive that are found in the Natura 2000 sites located in the Bidasoa and Oria river basins.

Specific objectives are to:

• Improve river connectivity by increasing the permeability of obstacles in rivers, restoring habitats and reducing impacts on watercourses, especially carrying out those measures identified as most effective;
• Increase knowledge of how to manage and restore these resources; and
• Disseminate project results and raise public awareness on the environmental values and services the rivers provide.

Expected results:

• Achievement of a River Connectivity Index of “Very good. Absence of obstacles” for 11 obstacles;
• Achievement a River Connectivity Index of "Good. Obstruction with an efficient passage device for all types of fish” for the obstacle, the waterwheel of the "Goiko Errota" mill;
• Achievement a River Connectivity Index of "Moderate. Surmountable through an efficient device” for the C.H. Olaverri waterwheel;
• Elimination a total of 5 133 m of artificial lake sections (reservoirs) associated with the obstacles eliminated;
• Removal of 1.5 ha of artificial areas occupying the river territory;
• Restoration of 3.46 ha with alder and ash groves (habitat 91E0*) species and mixed Atlantic forest;
• Control and assessment of the American mink population in Navarre; and
• Introduction of a 40 m3/ha thick dead wood structure in the riverbeds along the sections covered in actions.