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This research work evaluates the dynamics of surface water-groundwater mixing using an openended
Lake of Ugbo-Nla and the adjoining groundwater of the shallow coastal wells as a
prototype study of surface water–groundwater interaction in coastal environment. Ten (10)
surface water samples were collected from the lake at different positions using research boat
while another ten (10) groundwater samples were collected from different shallow wells within
the community opposite to the sea. The water samples were analysed using Atomic Absorption
Spectroscopy (AAS) to determine the elemental concentrations. In addition, three Electrical
Resistivity Tomography (ERT) profiles were equally established along the coast of the surface
water body land-ward. Analysis of trace and major elemental compositions of water samples
from the two water bodies reveal possible interaction between them. The ERT data also
corroborate this interaction by showing low resistive zones at depth equivalent to the depth of the
coastal shallow wells. Structure that mimic flow path was mapped out under profile 3 with high
proximity to the surface water. The study has shown that active interaction exists between surface
and underground water.