Numerical assessment of riverbank filtration using gravel back filter to improve water quality in arid regions

Abstract

The main challenge of water resource management in high-stress regions, especially in developing countries, is in adopting non-traditional methods to obtain safe drinking water in desired quantities. In Egypt, the riverbank filtration (RBF) system is one of the most common solutions to solve rivers’ water quality issues. Several sites have been investigated, and the system has demonstrated tremendous potential. The drinking water plant in Embaba, Giza, Egypt, is considered in this study to improve the quality of the abstracted water through the vertical well system. The numerical code of MODFLOW and MT3D is used to simulate the impact of using the emplacement of the gravel-pack filter (GPF). Three different scenarios were investigated: the first consists of vertical GPF; the second is horizontal GPF for different geometries, depths, widths or thicknesses, lengths, and permeability of the filter material; and, the third is drilling a pipe filter through the riverbed for different pipe numbers, depths, and the material’s hydraulic conductivity. The results revealed that the riverbank filtration sharing (RBFS) rate was increased by increasing the filter width or thickness at the riverside, the filter pipe numbers, the length of the horizontal filter, and the permeability of filter material. At the same time, the thickness of the river bed decreased by increasing the filter width at the groundwater side. Also, the RBFS was increased by increasing the filter width or the thickness in the two directions and the pipe length. However, it returned to decrease again due to groundwater sharing. Thus, the RBF design should carefully consider the gravel-pack, pipe filter geometry, and permeability impact rate of RBFS.

A New Infrastructure for the Amazon

“…It is necessary to research new methods and technologies to promote safe drinking water for people, but also for domestic use, food production, and other purposes 78 . Solutions to improve potable water access could include rainwater harvesting and storage 79 ; riverbank filtration 80 ; protection of wells and springs 81 ; water filtration systems with biosand filters, ceramic filters, or membrane filters to remove contaminants and pathogens from the water 82 ; boiling and/or chlorinating water before drinking it to kill harmful microorganisms 83 ; and UV water purifiers 84 .…”

Una Nueva Infraestructura para la Amazonía

“…Es necesario investigar nuevos métodos y tecnologías para promover el agua potable para las personas, pero también para uso doméstico, producción de alimentos y otros fines 78 . Las soluciones para mejorar el acceso al agua potable podrían incluir la recolección y almacenamiento de agua de lluvia 79 ; filtración ribereña 80 ; protección de pozos y manantiales 81 ; sistemas de filtración de agua con filtros de bioarena, filtros cerámicos o filtros de membrana para eliminar contaminantes y patógenos del agua 82 ; hervir y/o clorar el agua antes de beberla para matar microorganismos dañinos 83 ; y purificadores de agua UV 84 . Una opción interesante para la Amazonía, donde llueve abundantemente, es la recolección doméstica de agua de lluvia (DRWH).…”

Investigating Climate Change Effects on Evapotranspiration and Groundwater Recharge of the Nile Delta Aquifer, Egypt

“…Water resources are one of the most important natural resources worldwide [1,2]; sustainable management plans are essential for ensuring the long-term availability of these sources, especially in arid and semi-arid regions [3][4][5][6]. The agriculture sector is the highest water consumer.…”