This paper describes a gully erosion study undertaken at Umuagwo – Urualla in the Ideato North Local Government Area of Imo State, Nigeria. The study involved the morphometric measurement of the gully, collection of soil samples for geotechnical analysis, geophysical investigation (using Vertical Electric Sounding) to determine the subsurface complexities of the gully area, peizometric measurement to determine response to hydraulic pressure as well as landuse/landcover of the study area. VES result indicate that the subsurface complexity of the gully is underlain by shale and siltstone while its overburden is constituted of sandy or loose soil materials which is permeable to a depth of about 32.5m where shale formation begins to predominate forming a semi-impermeable layer to the infiltrating water. The geotechnical characteristics of soil are predominantly sands whose fines (silt/clay) are very negligible. The sands are loose and highly permeable, and are non-plastic, cohesion is small (3kN/m2), Angle of internal friction 24° Shear strength 177.8 kpa. The study found out that the area has fast lost its thick vegetation to light vegetation and has resulted in surface runoff. The poor soil quality, upward seepage and out flowing of groundwater weakened the cohesive force of the soil thereby encouraging the sliding of overburden materials resulting in the formation and growth of the gully.
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