Sujal Filter Description

Pasted Graphic
Source: TRDDC


The filter developed by TRDDC uses rice husk ash, pebbles and a binder for the fabrication of the filter bed. Various types of containers can be used for housing the bed. These could be plastic buckets, plastic pipes or even earthen pots. The choice depends on the requirement and affordability. The filters can be produced either in a factory setting by a village entrepreneur or can be made in a "do-it-yourself" mode.

Tata Research Development and Design Centre


Contaminant Removal
Water from different sources with widely varying levels of contamination is filtered through the above filters and the characteristics such as pH, turbidity and bacterial count are thoroughly tested. In all the cases, the filtered water from TRDDC filters is equivalent to or better than the tap water supplied by the public water works departments in cities. The water is eminently of drinkable quality in terms of pH, turbidity and bacterial count. For example, the turbidity of canal water decreases from 10.5 to 0.35 (NTU) and the bacterial count from 17,556 MPN/100ml to 940 MPN/100ml after filtration (92–98% bacterial trapping). Even in the case of extremely contaminated water, TRDDC filters are found to give excellent results through double filtration, giving both the turbidity and the bacterial count well within the potable limits.

Flow Rate
The filtration rate is 2 litres/hour and may vary depending on the design. A range of 20-30 litres/day is possible, which is adequate for small to medium size families.

Technology Dissemination
TRDDC is working with 25 NGOs along with UNICEF to proliferate the water filter to the rural masses. The filter making technology was successfully transferred to 200 personnel from 25 NGOs through workshops and training programs. In 2001, Tata Consultancy Services supplied more than 500 water filters to the victims of the Gujarat earthquake. It also transferred the filter fabrication technology to the victims to enable maintenance and sustained use of the filters. Already more than 3000 filter units have been fabricated for use in rural households.


Both the initial cost and replenishment cost of the filters is much lower compared to any of the currently available commercial filters in India.


References & Links

Important Notice

The current Sujal water filter is undergoing improvements. Training and fabrication has been stopped for the time being.

Contact Information

Tata Research Development and Design Centre
Maj Gen B. G. Shively, AVSM (Retd), Consulting Advisor
Tata Consultancy Services Ltd.
54-B, Hadapsar Industrial Estate
Pune, India, 411 013

Telephone: +91-020 -66086325
Fax: +91-020 -66086399

Email: b [dot] shively [at] tcs [dot] com