In 2025, a comprehensive geo-engineering investigation was carried out in an active landslide area affecting Road 348 (Palmach Street) in Tiberias, Israel, along a ~150–400 m section southeast of the roundabout at the junction with Road 90. The site is located within a well-documented landslide-prone slope, where multiple instability events have been recorded over past decades in the surrounding area, and it is also characterized by elevated seismic susceptibility.
The slope exhibits complex geological and geotechnical conditions, consisting of a fractured and weathered basalt cap overlying weak marl–chalk formations (Bira–Gesher formations), with a heterogeneous cover of talus and anthropogenic fill. This stratigraphic configuration promotes the development of shear zones, particularly at the basalt–marl interface. The marl units are highly sensitive to wetting, and their shear strength is expected to decrease significantly under increased moisture conditions.
The investigation included a review of previous studies, field reconnaissance and mapping of surface deformation features, and a new drilling campaign comprising 12 boreholes (to depths of up to 50 m) completed in January–February 2025. Inclinometers were installed in all boreholes to monitor subsurface displacements. Two supplementary pile-drilling boreholes were performed in August 2025 to assess the presence of wet layers and perched groundwater conditions. The combined drilling and monitoring results indicate a large-volume landslide, with displacement depths reaching approximately 26 m and a general movement direction toward the northeast. The inferred slip surface is located within the marl sequence, near transitions between marl and basalt or between marl and talus, and additional deformation was also observed within the talus deposits.

A combined stabilization concept was proposed to improve long-term stability and protect the roadway, including unloading by removal of part of the sliding mass, together with a pile wall and rock anchors to support the road and stabilize the slope.