Applying an EGMS-based approach to assess potential ground movement impacts on Spain's coastal municipalities

A recent article using data from the European Ground Motion Service (EGMS) to assess the vulnerability of the Spanish coastline to ground movements was published in October 2024 (López-Vinielles et al., 2024). The study, funded by the “Plan de Recuperación, Transformación y Resiliencia - Financiado por la Unión Europea - Next Generation EU” programme and conducted within the framework of the RISKCOAST project (Ref. SOE3/P4/E0868), the EGMS RASTOOL project (Grant Agreement No. 101048474), and the SARAI project (PID2020-116540RB-C22), examines the coastline's exposure to ground movements and their potential impacts on roads, buildings, and populations.

Utilizing a suite of post-processing tools including ADAfinder, 9,010 Active Deformation Areas (ADAs) across 805 coastal municipalities were identified, with 1,916 affecting roadways and 2,596 affecting buildings. Most ADAs exhibited vertical movement due to land subsidence, while horizontal movements, mainly linked to landslides, were also significant. The majority of ADAs showed moderate to low displacement rates (<25 mm/yr). The potential economic impact was estimated at €19,428.4 million, with €1,716.4 million attributed to roads and €17,712.0 million to buildings. Additionally, 134,236 people were identified as potentially vulnerable.

The study highlights a higher exposure of Spain's Mediterranean coast compared to the Atlantic coast, and a higher exposure of the Canary archipelago compared to the Balearic Islands. Andalusia and Murcia are identified as the most vulnerable regions. The higher exposure of the Mediterranean coast is particularly evident in the southern Mediterranean, where rapid tourist expansion and extensive urban and infrastructure development increase the incidence of ground motion processes affecting built-up areas. Specifically, climatic conditions and intense water demand along this stretch of coast have led to aquifer overexploitation, contributing to widespread land subsidence. Additionally, landslides pose a significant concern along this region, particularly in the Alpine mountain ranges running parallel to the coast.

The research underscores the potential of the EGMS for conducting both preliminary population exposure analyses and preventive risk assessments to mitigate road and building damage. While the study provides a static overview of the potential socio-economic impact of ground motion on the Spanish coast, the EGMS offers significant potential for ground movement mapping across Europe, making it an invaluable tool for risk management, particularly in regions experiencing rapid urban and infrastructure expansion. In this context, the work represents a first step towards developing new EGMS-based applications for impact assessment.

Reference

López-Vinielles J., Ezquerro P., Béjar-Pizarro M., Sarro R., Cuevas-González M., Barra A., Mateos R.M. (2024). Potential socio-economic impacts of ground movements in the coastal municipalities of Spain: Insights from the supra-regional implementation of the European Ground Motion Service. Ocean and Coastal Management, 259, art. no. 107452. https://doi.org/10.1016/j.ocecoaman.2024.107452