| Autor: |
Hassan, Nasir Abdi, Gathenya, John M., Raude, James M. |
| Předmět: |
|
| Zdroj: |
Journal of Sustainable Research in Engineering; 2022, Vol. 7 Issue 1, p31-45, 15p |
| Abstrakt: |
Groundwater recharge has become a significant practice for sustainable groundwater development and efficient water resource management. Many countries in Africa including Kenya are currently experiencing water scarcity. Kakia and Esamburmbur subcatchment, Narok County in southwest Kenya suffers water shortage during the dry season and surface water sources dry up. Identifying groundwater recharge zones and estimating groundwater recharge rates in Kakia and Esamburmbur sub-catchment will help water-resource authorities and policymakers to properly plan and develop groundwater resources in the sub-catchment. A geophysical survey was executed using the PQWTs-500 equipment to map the sub-surface condition of the study area in order to determine the suitable recharge zones. Five profile lines were generated of 20.9 km in total with 104 points at 200 m intervals. Soil and Water Assessment Tool plus (SWAT+) model was used to estimate groundwater recharge rates in the sub-catchment. The SWAT+ model was calibrated and validated with seventeen years (2003 - 2019) of monthly satellite soil moisture data. Model performance values obtained for calibration and validation were coefficient of determination (R²) 0.51 and 0.59, Nash-Sutcliffe efficiency (NSE) 0.17 and 0.20, and percent bias (PBIAS) 33.8% and 28.5% respectively. The geophysical survey results showed that the south-central and southeast zones of the sub-catchment are potentially good groundwater recharge zones and therefore suitable for managed aquifer recharge structures to augment the groundwater resources. Additionally, the SWAT+ simulation showed that the long-term average groundwater recharge rate ranges from 0 to 175 mm per year. It was also observed that the highest groundwater recharge occurs in April, May and, June. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
