TY - JOUR
T1 - A preliminary analysis of the hydrogeological conditions and groundwater flow in some parts of a crystalline aquifer system
T2 - Afigya Sekyere South District, Ghana
AU - Yidana, Sandow Mark
AU - Essel, Stephen Kwaku
AU - Addai, Millicent Obeng
AU - Fynn, Obed Fiifi
N1 - Publisher Copyright:
© 2015 Elsevier Ltd.
PY - 2015/4/1
Y1 - 2015/4/1
N2 - A steady state groundwater flow model was calibrated to simulate the complex groundwater flow pattern in some crystalline aquifer systems in north-central Ghana. The objective was to develop the general geometry of the groundwater system and also estimate spatial variations in the hydraulic conductivity field as part of efforts to thoroughly investigate the general hydrogeology and groundwater conditions of aquifers in the area. The calibrated model was used in a limited fashion to simulate some scenarios of groundwater development in the terrain. The results suggest the dominance of local groundwater flow systems resulting from local variabilities in the hydraulic conductivity field and the topography. Estimated horizontal hydraulic conductivities range between 1.04. m/d and 15.25. m/d, although most of the areas consist of hydraulic conductivities in the range of 1.04. m/d and 5.5. m/d. Groundwater flow is apparently controlled by discrete entities with limited spatial interconnectivities. Recharge rates estimated at calibration range between 4.3% and 13% of the annual rainfall in the terrain. The analysis suggests that under the current recharge rates, the system can sustain increasing groundwater abstraction rates by up to 50% with minimal drawdown in the hydraulic head for the entire terrain. However, with decreasing groundwater recharge as would be expected in the wake of climate change/variability in the area, increased groundwater abstraction by up to 50% can lead to drastic drawdowns by more than 25% if recharge reduces by up to 50% of the current levels. This study strongly recommend the protection of some of the local groundwater recharge areas identified in this study and the promotion of local recharge through the development of dugouts and other conduits to encourage recharge.
AB - A steady state groundwater flow model was calibrated to simulate the complex groundwater flow pattern in some crystalline aquifer systems in north-central Ghana. The objective was to develop the general geometry of the groundwater system and also estimate spatial variations in the hydraulic conductivity field as part of efforts to thoroughly investigate the general hydrogeology and groundwater conditions of aquifers in the area. The calibrated model was used in a limited fashion to simulate some scenarios of groundwater development in the terrain. The results suggest the dominance of local groundwater flow systems resulting from local variabilities in the hydraulic conductivity field and the topography. Estimated horizontal hydraulic conductivities range between 1.04. m/d and 15.25. m/d, although most of the areas consist of hydraulic conductivities in the range of 1.04. m/d and 5.5. m/d. Groundwater flow is apparently controlled by discrete entities with limited spatial interconnectivities. Recharge rates estimated at calibration range between 4.3% and 13% of the annual rainfall in the terrain. The analysis suggests that under the current recharge rates, the system can sustain increasing groundwater abstraction rates by up to 50% with minimal drawdown in the hydraulic head for the entire terrain. However, with decreasing groundwater recharge as would be expected in the wake of climate change/variability in the area, increased groundwater abstraction by up to 50% can lead to drastic drawdowns by more than 25% if recharge reduces by up to 50% of the current levels. This study strongly recommend the protection of some of the local groundwater recharge areas identified in this study and the promotion of local recharge through the development of dugouts and other conduits to encourage recharge.
KW - Climate change
KW - Hydraulic conductivity
KW - Recharge
KW - Voltaian
UR - http://www.scopus.com/inward/record.url?scp=84925541030&partnerID=8YFLogxK
U2 - 10.1016/j.jafrearsci.2014.12.011
DO - 10.1016/j.jafrearsci.2014.12.011
M3 - Article
AN - SCOPUS:84925541030
SN - 1464-343X
VL - 104
SP - 132
EP - 139
JO - Journal of African Earth Sciences
JF - Journal of African Earth Sciences
ER -