Abstract

This study assessed the handling and effectiveness of Bio-Sand-Filters (BSFs) in filtering water for human drinking purposes in households within Morogoro Municipality, Tanzania. Water microbiological parameters (such as Escherichia coli, total viable counts (TVC), and total coliforms) and physico-chemical properties (including turbidity and pH) were analyzed before and after filtration. Escherichia coli levels were below the quantification limit (<1 Log CFU/ml) in the unfiltered water, while TVC ranged from 2.2 to 2.9 Log CFU/ml and coliforms ranged from <1 to 2 Log CFU/100 ml. In filtered water samples, both total viable counts and total coliforms significantly decreased to <1 Log CFU/ml. Turbidity reduced from 7 Nephelometric Turbidity Units (NTU) in unfiltered water to 6 NTU in filtered water samples. The pH of unfiltered water samples varied from 6.5 to 7.7, whereas that of filtered water ranged from 6.8 to 7.8. Overall, BSFs can significantly reduce microbiological contamination and water turbidity to meet required standards without the need for thermal or chemical treatments. This water filtration technique is relatively cheaper than conventional boiling and chemical treatment methods, making it the best option for resource-poor households.

Key words: Bio-sand filter, water microbiology, water filtration, turbidity, pH, Nephelometric Turbidity Units (NTU), total viable counts (TVC).