Transient Electromagnetic Surveys for Groundwater Investigations Near the Kakuma Refugee Camp, Kenya

The Kakuma refugee camp is one of the largest refugee camps in the world. Located in an arid region of northwestern Kenya, the camp and the surrounding communities rely extensively on groundwater. While additional wells are planned to serve the increasing needs of the region, the choice of location is complicated by complex geology and hydrologic systems, and the presence of localised unsafe levels of fluoride. We conducted four geophysical campaigns to investigate the hydrology of the region, using towed and stationary transient electromagnetic (TEM) methods.

In this abstract, we present the results of approximately 700 TEM soundings plus over 300 linekilometres of towed TEM data, resulting in a pseudo-3D resistivity model of the approximately 140 square kilometre region. From this model, we interpreted the spatial extents of the geologic units in this area with particular interest in sandy sediments hydrologically connected ot the main ephemeral river channel. Ten sites were selected and two will be drilled by July 2025. Ongoing correlation of chemical analyses with resistivity structures will help constrain sources of fluoride and optimise placement of new wells as the hydrologic development of the area continues.