21/10/2025
Such slope failure modes can be detected by analyzing potential saturation zones - simply by superimposing the Topographic Wetness Index (TWI) over the planned earthwork grades as both relict paleo-drainage and progressively formed preferential flow paths can act as hidden conduits under fills, transmitting subsurface water until pore pressures rise.
TWI not only delineates areas prone to subsurface saturation, but also enables strategic planning of drainage outfalls - preventing toe material weakening due to concentrated flow or prolonged discharge.
The observed slope feature suggests a subsurface conduit of saturation, either pre-existing or progressively developing, that has built up under undrained conditions until failure, most likely due to seismically exacerbated FOS reduction.
When subsurface saturation is suspected—regardless of its origin—it can be effectively detected and visualized using Electrical Resistivity Tomography (ERT), one of the core components of our three-pronged HydroGeo approach:
🌐 Remote Sensing, ⚡ Geophysical Mapping, and 🧪 Soil Testing along anomalous zones identified by geophysical interpretation.
👉 At HydroGeo Envi-Consultancy Services, we specialize in pre-failure slope diagnostics and preventive geotechnical investigations—combining data-driven models with field-based validation to mitigate risks before they manifest. Hell, we even do post-failure troubleshooting if it still helps!
