Bio-Sand Filter (BSF): A Simple Water Treatment Device for Safe Drinking Water Supply and to Promote Health in Hazard Prone Hard-to-Reach Coastal Areas of Bangladesh

Abstract

Abstract: This study investigated a locally assembled ‘Bio-Sand Filter (BSF)’ water treatment device for low cost household level drinking water supply in hazard-prone hard-to-reach coastal areas of Bangladesh to promote health. The device was made using locally available materials (plastic bucket, sand and gravel). Overall study results revealed a greater portion of turbidity reduction (>99%) in the filtrate. The filter was found to reduce 1.5-log of total coliform and 1.6-log of fecal coliform, though it is not capable of consistently meeting the WHO guideline to be less than 1 CFU per 100 ml for both fecal and total coliform. The chlorination results showed that 2.4 mg/L chlorine doses were effective in post treatment of the filtrate and meet the recommended WHO guidelines to have free chlorine at least 0.5 mg/L to 1.0 mg/L in the stored water after 24hr to protect water from recontamination. The results led to the conclusion that one device could provide enough drinking water (24 to 50 L) to satisfy the needs of a large representative household. The filters reduce the risks of contamination between the water source and at the point of consumption through improving water quality that can be translated into improved health outcomes. Keywords: Bio-Sand Filter, Low-Cost Water Supply, Public Health, Hard-to-Reach Area