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This paper presents an overview assessment of the effectiveness and popularity of some methods adopted in measuring river bank filtration (RBF). The review is aim at understanding some of the appropriate methods used in measuring riverbank filtration, their frequencies of use, and their spatial applications worldwide. The most commonly used methods and techniques in riverbank filtration studies are: Geographical Information System (GIS) ( site suitability/surface characterization ), Geophysical, Pumping Test and borehole logging (sub-surface ), Hydrochemical, Geochemical, and Statistical techniques ( hydrochemistry of water ), Numerical modelling, Tracer techniques and Stable Isotope Approaches ( degradation and contaminants attenuation processes ). From the summary in Table 1, hydrochemical, numerical modelling and pumping test are the frequently used and popular methods, while geophysical, GIS and statistical techniques are the less attractive. However, many researchers prefer integrated approach especially that riverbank filtration studies involve diverse and interrelated components. In term of spatial popularity and successful implementation of riverbank filtration, it is explicitly clear that the popularity and success of the technology is more pronounced in developed countries like U.S. and most European countries. However, it is gradually gaining ground in Asia and Africa, although it is not far from its infancy state in Africa, where the technology could be more important considering the economic status of the region and its peculiarity when it comes to water resources predicaments. [ABSTRACT FROM AUTHOR]

Bank filtration (BF) is an attractive, robust and reliable water treatment technology. It has been used in Europe and USA for a long time; however experience with this technology so far is site specific. There are no guidelines or tools for transfer of this technology to other locations, specifically to developing countries. A four-step methodology was developed at UNESCO-IHE to analyse feasibility and to predict the performance of BF for water treatment. This included (I) hydraulic simulation using MODFLOW; (ii) determination of share of bank filtrate using NASRI BF simulator; (iii) prediction of water quality from a BF system using the water quality guidelines developed and (iv) comparison of the costs of BF systems and existing conventional surface water treatment systems for water treatment. The methodology was then applied to assess feasibility of BF in five cities in Africa. It was found that in most of the cities studied BF is a feasible and attractive option from hydraulic, water quality as well as operational cost considerations. Considerable operational and maintenance costs saving can be achieved and water quality can be further improved by switching from conventional chemical-based surface water treatment to BF or at least by replacing some of the treatment units with BF systems. [ABSTRACT FROM AUTHOR]