Construction & Installation

Proper construction of the filter box, preparation of the media, and installation of the sand is challenging, but is of critical importance to the effectiveness of the biosand filter. This section of the website explores some of the challenges which the BSF technician may face.

Designs & Modifications

Why is the present V10 biosand filter the way that it is? What about building a filter out of PVC pipe, or sheet metal? What is a Kanchan filter? This section of the website looks at the history and rational behind the biosand filter design, and alternative designs for the biosand filter.

Operation & Maintenance

The biosand filter is a living ecosystem. This section explores challenges related to how to use and maintain a biosand filter to ensure it remains effective.


Results of trials showing biosand filter performance at removing different contaminants and under different conditions.

Project Implementation
Support for starting or improving your biosand filter project.                                                                                                                                                        
Biosand Filter

Latest additions

Reductions of E.coli, MS2 and PRD-1 increases as filtration rate declines. Biosand filters using crushed granite as the filtration media has superior virus reductions than using Accusand silica as the filtration media, only when the media is not backwashed. E. coli reduction did not differ significantly between the two types of filter media. (Elliott, M.; Stauber, C.; DiGiano, F.; de Aceituno, A.; Sobsey, M. 2015)
Moving concrete and plastic bucket biosand filters 1 km after 9 months of operation reduced the hydraulic loading rate but significantly increased E. coli removal. (Napotnik, J.; Jellison, K. 2014)
Projects aiming to improve health cannot be just technology-driven, or the technology will under perform. Field situations are complex, and a holistic approach must be taken. (Voth-Gaeddert, L.E.; Divelbiss, D.W.; Oerther, D.B. 2015)
This study investigated the effect of grain size, hydraulic loading rate, batch residence time, and diffuser design on the performance of the CAWST biosand filter. Coarser grain size reduced bacterial removal efficiency. Longer residence time, on the other hand, improved bacteria removal. In terms of diffuser design, smaller holes and tighter spacing reduced bacterial removal efficiency. (Chan, C.C.V.; Neufeld, K.; Cusworth, D.; Gavrilovic, S.; Ngai, T. 2015)