Am J Trop Med Hyg 2011 vol. 85 no. 2 309-317
An Assessment of Continued Use and Health Impact of the Concrete Biosand Filter in Bonao, Dominican Republic
Benjamin A. Aiken*, Christine E. Stauber, Gloria M. Ortiz and Mark D. Sobsey
Address correspondence to Benjamin A. Aiken, Department of Environmental Sciences and Engineering, University of North Carolina—Chapel Hill Gillings School of Global Public Health, CB 7431 Rosenau Hall 148, Chapel Hill, NC 27599-7431. E-mail: benjamin_aiken@med.unc.edu
The biosand filter (BSF) is a promising point of use (POU) technology for water treatment; however there has been little follow-up of initial implementation to assess sustainability. The purpose of this study was to examine continued use, performance, and sustainability of previously implemented concrete BSFs in Bonao, Dominican Republic. Of 328 households visited and interviewed, 90% of BSFs were still in use after approximately 1 year since installation.
Water-quality improvement, measured by fecal indicator bacteria reduction, was found to be 84–88%, which is lower than reductions in controlled laboratory studies but similar to other field assessments. In a short prospective cohort study comparing BSF to non-BSF households, odds of reported diarrheal disease in BSF households were 0.39 times the odds of reported diarrheal disease in non-BSF households. These results document high levels of sustained and effective concrete BSF use and associated improvements in water quality and health.