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In the present work, the case of the Cármenes del Mar resort (Granada, Spain) is shown. It can be considered one of the most extreme examples on the Mediterranean coast of severe pathologies associated with urban development on coastal landslides. The resort, with 416 dwellings, was partially built on a deep-seated landslide which affects a soft formation composed of dark graphite schists. In November 2015, the City Council officially declared a state of emergency in the resort and 24 dwellings have already been evacuated. We have used two remote sensing techniques to monitor the landslide with the aim of identifying and measuring a wide range of displacements rates (from mm/year to m/year): (1) PSInSAR, exploiting 25 ENVISAT SAR images acquired from May 2003 to December 2009, and (2) photogrammetry, considering the output from two Unmanned Aerial Vehicle (UAV) flights made in June 2015 and January 2016 and the outdated photos from a conventional flight in 2008. The relationship between the geology of the site, data from PS deformation measurements, building displacements, rainfall and damage observed and their temporal occurrence allows a better understanding of the landslide kinematics and both the spatial and temporal evolution of the instability. Results indicate building displacements of up to 1.92 m in 8 years, a clear lithological control in the spatial distribution of damage and a close relationship between the most damaging events and water recharge episodes (rainy events and leaks from swimming pools and the water supply network). This work emphasises the need to incorporate geohazards into urban planning, including policies to predict, prepare for and prevent this type of phenomenon. © 2016, Springer-Verlag Berlin Heidelberg.

In the present work, we show the case of Marina del Este resort, located in the southern Mediterranean coast of Spain (Costa del Sol). A medium-scale landslide has been recognized when the area was virgin. In 1977 started the initial works for urbanizing the area; later, buildings and facilities expanded uphill covering the landslide body. This case is characterized by a long history of corrective drainage and mitigate measures without success. An analysis of the landslide activity has been carried out by applying different approaches and based on the combination of the following: (1) geomorphological analysis, (2) PSInSAR technique application (ENVISAT 2003-2009), (3) an assessment of building and infrastructure damages, (4) rainfall time series analysis and (5) ground monitoring (2010-2011) data interpretation. Results show that, from 2003 to 2009, the landslide was active with velocities ranging from 5 to 15 mm/year. During the exceptional rainy period in winter 2009-2010, the movement velocity increased about ten times (velocities ranging from 40 to 90 mm/year) causing widespread damages in the resort. Buildings with high degree of damage are located at the toe of the landslide, close to the marina, where some dwellings have been evacuated. Marina del Este is a good example to show that landslides on coastal and steep slope areas are very vulnerable to reactivations and require thorough studies before any anthropic modification.