In Chakwal, highy turbidity rainwater runoff and streamflows are collected in Khokhar Zar Dam to be used for water supply. Slow sand filtration (SSF) is a low-cost technology for treating raw water with turbidity below 50 NTU. Objectives of the work reported here include: study of current treatment process and highlight problems related to quality management, design and construct a pilot scale upflow roughing filter plant and to determine the optimum coagulant dose for in-line roughing filtration. The pilot plant constructed could reduce raw water turbidity from 450 NTU (Avg) to 2-10 NTU...