| Jal-TARA
Filter for Bacteria Free Water
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Health and Environment are two major concerns that arise in the context of economic development. Health is a major concern because the object of development is to meet people’s needs, wherein maintenance and improvement of health is obviously one of the most important needs of the masses. The issue of Health assumes a special significance in developing countries where there is widespread prevalence of preventable diseases, many of which are water borne or water related.
Water borne diseases form the largest single category of communicable diseases contributing to infant mortality (WHO, 1992). Their prevention requires drastic improvement in water quality. In India, about 21% of all communicable diseases (11.5% of all diseases) are water borne in nature. According to an estimate, 73 million working person days are lost every year owing to the people falling ill due to water borne diseases (VHAI, 1997) Diarrhea, which is the most prevalent water born disease, is responsible for 25-30% of deaths among children below five years of age. Also, epidemics of infectious hepatitis, food poisoning and typhoid fever are quite common.
To prevent the incidence of water borne diseases, there is a need to improve the quality of drinking water. Chemical treatment (chlorination) of water is the most widely used method to remove bacterial and other pathogenic contamination. Improper doses of chlorine and its consequent impacts are the two serious drawbacks of this chemical treatment. Hence, the need for a water-purification system that is not chemical based, easy to operate with a low maintenance and recurring cost.
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Different Diseases associated with water can be divided into four groups |
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| Water borne |
These diseases arise from the contamination of water by animal or human faeces or urine infected by pathogenic bacteria or virus, which are directly transmitted when water is drunk or used in preparation of food e.g. cholera, diarrhoea. |
| Water washed |
These diseases stem from indirect infection arising from lack of personal hygiene. All water borne diseases are ‘water washed’ diseases as well. |
| Water based |
These diseases are caused by ingestion of intermediate host or penetration of wet skin e.g. Schistosomiasis. |
| Water related | These diseases stem from infection carrying vectors, causing Malaria, Philariasis, Encephalitis, etc. |
The Environment Systems Branch of Development Alternatives initiated the research and development of the water purification system ‘Jal-TARA Filter’ in the year 1998. The objective of the project is to provide safe drinking water, free from bacterial contamination, at community and household levels. In contrast to other purification systems available in the market that are based upon chemical treatment, Jal-TARA filter is based on natural filtration without the use of chemicals. This filter is based on the slow sand filtration technique. It is designed in such a way that it ensures bacteria free water. It also removes the suspended solids and turbidity present in water. It gives an output of 2000 litres - 4000 litres per day, hence it can be used to supply bacteria free water to about 200 households. Jal-TARA filter, after rigorous laboratory testing, is in the field trial stage. Its results are very encouraging and this can be a simple solution to many complicated problems. q
Nishant Bhardwaj