Description

Abstract: Unsafe drinking and domestic water is a major community and public health concern in the River Njoro watershed. Lowcost household water treatment was identified as an intervention to address the problem, and the BioSand filter (BSF) was selected as the most sustainable and appropriate technology to develop for river-using households in the Njoro watershed. This brief summarizes results of a three-phase research program to develop and adapt the BioSand filter for local production and use, and test its effectiveness, acceptability, and health impacts with the population segment using river water for domestic and drinking in the Njoro and similar areas. Laboratory experiments showed sand grain size, residence time, and hydraulic loading rate have significant effects on the microbiological removal performance of the BSF. By adapting these design and operating parameters to better match local water source characteristics prior to local commercialization, performance can be significantly improved. In a six-month trial of the adapted local filter design with 30 rural and periurban households in the Njoro watershed, average removal performance matched controlled laboratory performance for indicator bacteria and viruses. The filters also demonstrated a very high level of user satisfaction and good evidence of commercial demand.