Geophysical Survey & Groundwater Resources Assessment, South Sudan

Case studies

Geophysical Survey & Groundwater Resources Assessment, South Sudan

Fashoda County, South Sudan 2020

Solidarités International engaged Groundwater Relief in November 2020 to undertake the study in Fashoda County to assess the available groundwater supply potential in the area for provision of clean drinking water to IDPs and the host communities in the area. The study location is in Upper Nile State in the north east of South Sudan. Previous hydrogeological studies of the area were extremely limited.

The work was completed by Paul Evans (Groundwater Relief) and David Ndago (Rapid Response Team) in December 2020 and comprised a hydrogeological desk study followed by a surface geophysical survey. The survey methodology was based on an integrated approach of electrical horizontal profiling, vertical electrical sounding (VES) and electrical resistivity tomography (ERT). Access to the survey sites was challenging due to flooding and lack of roads; where Landcruiser access was not possible, donkey and boat transport were required to transport the geophysical equipment.

The survey was successfully completed across over a period of 17 days. 1D and 2D resistivity data analysis and inversion were undertaken to characterise the ground conditions and to develop a hydrogeological conceptual model for the area. The project findings were used to identify areas where groundwater supply development may be feasible to inform long term project planning. The findings were presented to senior members of the Ministry of Water in Juba in collaboration with Solidarités International.