Past, present and future monitoring at the Vallcebre landslide (Eastern Pyrenees, Spain)

Works carried out to monitor the displacements of the Vallcebre landslide (Pyrenees range, NE of Spain) since 1987 are presented. The landslide, which extends over an area of about 0.8 km2 and affects more than 20 × 106 m3, has experienced displacements of up to one meter per year in some points and periods. It has been periodically monitored since 1987, using a wide range of surface and in-hole techniques: triangulation with theodolite, Terrestrial Photogrammetry, Electronic Distance Measurement, GNSS-GPS, inclinometers, wire extensometers, piezometers, DInSAR (satellite) and GBSAR (terrestrial). The results obtained using new techniques are compared with those obtained with GNSS-GPS and a wire extensometer, and checked against fixed stable points. From this comparison, we conclude that even though wire extensometers and inclinometers may have the highest precision, in practice, all systems play potentially valuable roles in providing meaningful data for monitoring at different study stages. In the near future, we envisage the installation of a Distributed Fiber Optic array to monitor the risk with a certain space and time continuity. After the evaluation of the precision and advantages of the different methods, the complementary use of some of them is strongly recommended.

The three decades work summarized here has been funded mainly by EC and Spanish Research Projects. In chronological order: TESLEC (Temporal stability and activity of landslides in Europe with respect to climatic change; EC; contract EV5V-CT94.0454); NEWTECH (New technologies for landslide hazard assessment and management in Europe; EC contract ENV4-CT96-0248 and Spanish CICYT contract AMB96-2480-CE); CICYT project (Cartografía de la susceptibilidad a los deslizamientos del terreno en el área del Alto Llobregat … Vallcebre mediante los SIG; Spanish CICYT contract AMB97-1091-C06); MODEVALL (Modelación hidrológico-mecánica del deslizamiento de Vallcebre; Spanish Science and Education Ministry, MEC, contract CGL2005-05282); SAFELAND (Living with landslide risk in Europe: Assessment, effects of global change, and risk management strategies; EC, 7thFP, grant agreement 226479); PYRMOVE (Research network funded by AGAUR, Government of Catalonia; grant number 2014CTP00051); PYRMOVE (Prevention and cross-border management of risk associated with landslides; funded by Interreg V-A, POCTEFA, and by the European Regional Development Fund, ERDF; project EFA364/19). The last project is still active.

Peer Reviewed

Postprint (published version)