Tube well and ground water
Ground water is the preferred source of water in many countries in order to avoid human pathogens. However this is not always the situation, depending upon the depth of the the tube well and the age of the water, there may well be biological contamination. The ground water may be a few hours to many thousands of years old, the older the water, the less likely there will be viable pathogens in the supply.
Over the last 40 years there has been a huge increase in the number of tube wells in an effort to obtain water that is non pathogenic. Contaminated water can cause diarrhoea disease and dehydration leading to mortality amount infants and the elderly. This was the main drive to sink tube wells and 10's of millions have been drilled in India and around Asia and Africa. Many aid agencies also just drill tube wells and fit a pump, without analysing the water, of checking the quality on a regular basis. As a consequence, in countries such as;
- India, West Bengal
- Vietnam, Red River
and many other locations, the water has very high arsenic concentrations, the following are some other issues.
- ferric & manganese
We are now in a situation in Bangladesh and India where we have the greatest human poisoning in history, attributed to arsenic and most of it was funded by the world bank and aid agencies. The upper limit for arsenic is 10ppb, filtration systems such as CAFE should be used to treat all water, including tube well ground water.