Author(s): Alban Kuriqi; Ismail Abd-Elaty
Linked Author(s): Alban Kuriqi
Keywords: No Keywords
Abstract: This study explores the profound impact of the Grand Ethiopian Renaissance Dam (GERD) in the Nile Delta aquifer under different potential filling scenarios, particularly under minimum and normal flow conditions, alongside the anticipated repercussions involving declining groundwater levels and increasing saltwater intrusion. The study involved three distinct scenarios, each simulating the filling of the GERD reservoir at different elevations: 600 m, 621 m, and 645 m above mean sea level (amsl). These scenarios were denoted as follows: Scenario #1 with a storage volume of 17 billion cubic meters (BCM), Scenario #2 with 37.30 BCM, and Scenario #3 with 74 BCM. In addition, these scenarios considered a collective sea level rise (SLR) of 25 cm and a reduction in the River Nile's hydrographs by 17 BCM, 20.30 BCM, and 36.70 BCM, respectively. This reduction was linked to an incremental increase in abstraction well rates, set at 25%, 50%, and 100%, respectively. The study's findings revealed that introducing a 25 cm SLR, coupled with GERD reservoir filling at 600 m, 621 m, and 645 m AMSL, particularly during the filling phases, could significantly impact the groundwater resources within the Nile Delta. Notably, these impacts were observed in alterations to the quality of freshwater within the Nile Delta. Specifically, the aquifer's salinity increased by 4.47% for Scenario #1,11.48% for Scenario #2, and a substantial 29.99% for Scenario #3. The construction and operation of GERD hold the potential to usher in a significant reduction in the Nile River's flow, particularly during the crucial filling stages of its reservoir. This decline will, in turn, have a cascading effect on the groundwater recharge in the Nile Delta aquifer. Forecasts point towards expected land subsidence in the Nile Delta area, with projections ranging from 52 mm for the first filling scenario to a staggering 260 mm for the third.
Year: 2024