Lessons from a Century-Tradition on Ecosystem-Based Disaster Risk Reduction (Eco-DRR) in Mountains: The Case of the Torrential System Los Arañones (Canfranc, Pyrenees)

Abstract

AbstractNatural hazards remain recurrent processes that often disrupt the status quo of communities and put the future welfare of people at risk. In the Pyrenees, extreme events related to floods, rockfall, landslides, or snow avalanches have recurrently affected transport corridors and human settlement. Coping with such impacts in the future requires paradigm change toward the implementation of Ecosystem-based disaster risk reduction (Eco-DRR) tools and land use. Yet, little is known about the reliability of these approaches in long term. Here, we review a long-term experience (more than a century) from implementing the Eco-DRR strategies, so-called Los Arañones, to protect the International Railway Station of Canfranc (Spain-France) against snow avalanches and torrential floods. The Eco-DRR implemented in Los Arañones consisted of two different strategies (i) at short term, innovative nature-based design dikes; and (ii) at long term, systematic reforestation of hill slopes. We show that, after more than a hundred years since forest engineers implemented these measurements (Benito Ayerbe, 1872–1917), they still can protect the existing infrastructure, although the cost of maintenance to keep the reliability of such Eco-DRR are steadily increasing. Our analyses call for further assessment of its effectiveness and efficiency under climate change stressors, to assure its reliability for the next decades. This example will cast light on implementing such Eco-DRR solutions in the other mountain regions worldwide.KeywordsNatural hazardClimate changeSnow avalanchesDebris floodsNatural-based solutionPyrenees