Groundwater-surface water interaction in Lake Nasser, Southern Egypt

Abstract

Abstract:A cross-sectional model, based on the two dimensional groundwater flow equation of Edelman, was applied at seven transects distributed over four geological cross sections to estimate groundwater heads and recharge from/or groundwater discharge to Lake Nasser. The lake with a length of 500 km and an average width of 12 km was created over the period [1964][1965][1966][1967][1968][1969][1970], the time for constructing the Aswan High Dam (AHD). The model, constrained by regional-scale groundwater flow and groundwater head data in the vicinity of the lake, was successfully calibrated to timeseries of piezometeric heads collected at the cross sections in the period 1965-2004. Inverse modeling yielded high values for the horizontal hydraulic conductivity in the range of 6.0 to 31.1 m day À1 and storage coefficient between 0.01 and 0.40. The results showed the existence of a strong vertical anisotropy of the aquifer. The calibrated horizontal permeability is systematically higher than the vertical permeability (%1000:1). The calibrated model was used to explore the recharge from/or groundwater discharge to Lake Nasser at the seven transects for a 40-year period, i.e. from 1965 to 2004. The analysis for the last 20-year period, 1985-2004, revealed that recharge from Lake Nasser reduced by 37% compared to the estimates for the first 20-year period, 1965-1984. In the period 1965-2004, seepage of Lake Nasser to the surrounding was estimated at 1.15 Â 10 9 m 3 year À1 . This led to a significant rise of the groundwater table. Variance-based sensitivity and uncertainty analysis on the Edelman results were conducted applying quasi-Monte Carlo sequences (Latin Hypercube sampling). The maximum standard deviation of the total uncertainty on the groundwater table was 0.88 m at Toshka (west of the lake). The distance from the lake, followed by the storage coefficient and hydraulic conductivity, were identified as the most sensitive parameters.

Groundwater and Surface Water Interaction at the Regional-scale – A Review with Focus on Regional Integrated Models

“…There is much focus on the interaction between groundwater and rivers and streams, while interaction with lakes and other non-flowing water bodies is underrepresented (see, e.g. Elsawwaf et al 2014;Tweed et al 2009). Dahl et al (2007) review different classification systems of GW-SW in a process-oriented manner and propose a new typology for these interactions, which can be used for a better comparison of different settings or sites.…”

Temporal-Spatial Evolution Analysis of Lake Size-Distribution in the Middle and Lower Yangtze River Basin Using Landsat Imagery Data

“…This is very important because the lakes benefit the society and ecology in the surrounding regions [31,41], and lake water is the most important water supply in aquaculture, industry, and domestic water use around the four lakes regions [42,43]. The 12-year monitoring data record can serve as additional data to assess and quantify the seasonal water conditions around the lakes.…”

Using multiple environmental methods to estimate groundwater discharge into an arid lake (Dakebo Lake, Inner Mongolia, China)

“…Energy, materials, and salinity are conveyed via hydrodynamic exchanges from groundwater to the surface water within the HZ; hydrodynamic exchanges are therefore important drivers of the migration and transformation of substances and biochemical processes (Shaw et al 2013;Lee et al 2014;Elsawwaf et al 2014;Rautio and Korkka-Niemi 2015). However, to date, studies of surface-water/groundwater exchanges have mainly focused on the HZ in rivers (Keery et al 2007;Storey et al 2003), and there has been a lack of studies on the HZ of lakes.…”