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

A household-scale sand filter incorporating a biomass layer was developed and tested in the laboratory. Filters performed better with thicker biomass layers. Filter effectiveness increased up to day 30, and declined after day 75. (Not a BSF) (Baig, S.A.; Mahmood, Q.; Nawab, B.; Shafqat, M.N.; Pervez, A. 2011)
Experiments in a lab found that a dual media column with a layer of manganese oxide coated sand and a layer of iron hydroxide coated sand was better at removing zinc than a column with just iron hydroxide coated sand. Both were better than a plain sand column at removing bacteria. (Ahammed, M.M.; Meera, V. 2010)
An experimental slow sand filter was able to remove nitrate without significantly increasing nitrite, but at very low flow rates (0.015 to 0.6 m/h). Nitrite accumulation increased with flow rate. Most removal occurred at the top of the filter. (Aslan, S.; Cakici, H. 2007)
Households which were using BSF had 61% less diarrhoea. After one year, 90% of BSF's were still in use, and were removing 88.4% of E. coli. (Aiken, B.A.; Stauber, C.E.; Ortiz, G.M.; Sobsey, M.D. 2011)