La era de la demolición de presas

Se quiere presentar las experiencias estadounidenses más significativas a la hora de demoler una presa. Primero explicando los pasos a seguir para obtener los permisos necesarios que autorizan demoler una presa, y a continuación mostrar las formas más comunes para conseguir financiar este tipo de obras. Por último nos gustaría presentar la nueva fundación internacional World Fish Migration Foundation focalizada en promover proyectos relacionados con la recuperación de las rutas migratorias de los peces, tanto a nivel divulgativo (Fish Passage Conference 2015), como de concienciación (World Fish Migration Day) y educacional (From Sea to Source Guidance)

Dam removal Europe: refuting myths and supporting professionals

The removal of dams and weirs has been happening for decades. Since the 90’s a few countries have increased this tendency. USA has already removed at least 1,300 dams. What very few people know is that in Europe there have been over 3,500 barriers demolished already. In some European countries, like France, Sweden, Spain, Finland and UK dams are mainly being removed due to existing legislation, safety and security, the need to reach a good ecological status of their rivers for the Water Frame Directive and/or economical reasons. However, the lack of awareness, knowledge, support by decision makers and funding for dam removal are generally bottlenecks and most of the times is the cause of many dam removal failures. In addition, the Renewable Energy Directive requires the EU countries to fulfil at least 20% of its total energy needs with renewables by 2020, and amongst these renewables is hydropower. All this makes dam removal projects tremendously difficult to those who are willing to start removing old and useless dams, and automatically makes dam removal an uncomfortable subject to bring up for politicians. Europe requires a shift towards adaptive management of stream barriers, one that maximizes benefits and minimizes impacts, one that keeps efficient dams and removes obsolete and abandoned dams. The goals of Dam Removal Europe (www.damremoval.eu) are to improve citizens’ awareness about removing dams and refute myths, create a reference community of professionals, experts and starters, who generates and shares knowledge about dam removal and putting dam removal on the agenda of policy makers, directors and managers

Dam removal Europe: refuting myths and supporting professionals

The removal of dams and weirs has been happening for decades. Since the 90’s a few countries have increased this tendency. USA has already removed at least 1,300 dams. What very few people know is that in Europe there have been over 3,500 barriers demolished already. In some European countries, like France, Sweden, Spain, Finland and UK dams are mainly being removed due to existing legislation, safety and security, the need to reach a good ecological status of their rivers for the Water Frame Directive and/or economical reasons. However, the lack of awareness, knowledge, support by decision makers and funding for dam removal are generally bottlenecks and most of the times is the cause of many dam removal failures. In addition, the Renewable Energy Directive requires the EU countries to fulfil at least 20% of its total energy needs with renewables by 2020, and amongst these renewables is hydropower. All this makes dam removal projects tremendously difficult to those who are willing to start removing old and useless dams, and automatically makes dam removal an uncomfortable subject to bring up for politicians. Europe requires a shift towards adaptive management of stream barriers, one that maximizes benefits and minimizes impacts, one that keeps efficient dams and removes obsolete and abandoned dams. The goals of Dam Removal Europe (www.damremoval.eu) are to improve citizens’ awareness about removing dams and refute myths, create a reference community of professionals, experts and starters, who generates and shares knowledge about dam removal and putting dam removal on the agenda of policy makers, directors and managers

More than one million barriers fragment Europe’s rivers

Rivers support some of Earth’s richest biodiversity1 and provide essential ecosystem services to society2, but they are often fragmented by barriers to free flow3. In Europe, attempts to quantify river connectivity have been hampered by the absence of a harmonized barrier database. Here we show that there are at least 1.2 million instream barriers in 36 European countries (with a mean density of 0.74 barriers per kilometre), 68 per cent of which are structures less than two metres in height that are often overlooked. Standardized walkover surveys along 2,715 kilometres of stream length for 147 rivers indicate that existing records underestimate barrier numbers by about 61 per cent. The highest barrier densities occur in the heavily modified rivers of central Europe and the lowest barrier densities occur in the most remote, sparsely populated alpine areas. Across Europe, the main predictors of barrier density are agricultural pressure, density of river-road crossings, extent of surface water and elevation. Relatively unfragmented rivers are still found in the Balkans, the Baltic states and parts of Scandinavia and southern Europe, but these require urgent protection from proposed dam developments. Our findings could inform the implementation of the EU Biodiversity Strategy, which aims to reconnect 25,000 kilometres of Europe’s rivers by 2030, but achieving this will require a paradigm shift in river restoration that recognizes the widespread impacts caused by small barriers

More than one million barriers fragment Europe’s rivers

Rivers support some of Earth’s richest biodiversity and provide essential ecosystem services to society, but they are often fragmented by barriers to free flow. In Europe, attempts to quantify river connectivity have been hampered by the absence of a harmonized barrier database. Here we show that there are at least 1.2 million instream barriers in 36 European countries (with a mean density of 0.74 barriers per kilometre), 68 per cent of which are structures less than two metres in height that are often overlooked. Standardized walkover surveys along 2,715 kilometres of stream length for 147 rivers indicate that existing records underestimate barrier numbers by about 61 per cent. The highest barrier densities occur in the heavily modified rivers of central Europe and the lowest barrier densities occur in the most remote, sparsely populated alpine areas. Across Europe, the main predictors of barrier density are agricultural pressure, density of river-road crossings, extent of surface water and elevation. Relatively unfragmented rivers are still found in the Balkans, the Baltic states and parts of Scandinavia and southern Europe, but these require urgent protection from proposed dam developments. Our findings could inform the implementation of the EU Biodiversity Strategy, which aims to reconnect 25,000 kilometres of Europe’s rivers by 2030, but achieving this will require a paradigm shift in river restoration that recognizes the widespread impacts caused by small barriers