AWWA WQTC65726

This powerpoint presentation begins by providing a brief overview of riverbank filtration (RBF), and presents the framework for assessing the feasibility of RBF that includes the following four step methodology developed at UNESCO-IHE: hydraulic simulation using MODFLOW; determination of share of bank filtrate and local groundwater using NASRI Bank Filtration Simulator; prediction of the water quality using algorithms/guidelines, developed based on literature review; and, comparison of the capital and O&M costs of RBF system with that of existing conventional water treatment system. Case studies in three cities of Malawi are presented. Conclusions were that: RBF is a robust natural water treatment system which has high potential for application in developing countries; a four-step methodology was developed for assessing feasibility of RBF for water treatment; spacing between the wells and distance of the wells from the bank can be varied to get the required water quality and quantity from the wells for given allowable drawdown; a guideline for estimation of water quality of RBF system for given travel time and travel distance was developed based on literature review; and, RBF is feasible in selected cities of Malawi, from Hydraulic, Water Quality as well as Cost considerations. Includes tables, figures.