Anyone building a house, commercial complex or an apartment today generally goes for drilling of borewells. Though the Bangalore Water Supply and Sewerage Board (BWSSB) has made it mandatory for registration of new borewells, there is not much information except in the media and in research and scientific institutions about groundwater, its quality and other details.
Though a majority of educated Bangaloreans are aware of the over exploitation of ground water and also the contamination, they too have limited access to such information.
Very few agencies have information on the groundwater, the water table, contamination and pother aspects. The Central Ground Water Board (CGWB), which comes under the Ministry of Water Resources, has come up with an information system about all these aspects.
The system not only gives information on the ground water availability but also on critically contaminated areas.
What makes the system important is that it also gives information to the public about long-term medical conditions and health hazards that contamination can cause.
The system says that 45 per cent of
water has high nitrate content. It also says that pollution is higher in
western parts of the city, where sewage is let out directly into Vrishabavathi
river. It also points out that water in all industrial belts like Peenya, Rajajinagar,
Hoskote and Bangalore Kanakapura Road
areas has high concentration of magnesium, chlorides and nitrates and all these
chemicals are harmful to human beings.
The groundwater in these areas are found to be slightly alkaline, indicating high concentration of chlorides and magnesium
and 83 other taluks of
district has high amount of
nitrosamines, which are carcinogenic. Research has shown that high levels of Nitrate
in potable water will cause the `Blue Baby' syndrome in infants, which alters
the blood's ability to carry oxygen. Bangalore
The idea behind the CGWB system was to ensure that people were given correct and accurate information that they could rely on and also educate the people about the dangers of over exploitation and contamination of water sources.
The board gas so far uploaded complete information on 22 taluks in Karnataka, including
, in the system and more will
follow. The board plans to translate the information, which is now available
only in English, into Kannada. Bangalore
The system has been made reader friendly by including maps of contaminated areas for every taluk and this can be easily accessed from the CGWB website.
The CGWB information states that 54 taluks have high fluoride content and 84 taluks have dangerous levels of nitrates. It lists 55 taluks as falling in the overexploited category. The situation is serious in the two districts of Kolar and Tumkur.
The CGWB says groundwater is overexploited by 190 per cent in Bangalore South, 198 per cent in Bangalore North and 206 per cent in Anekal. It classifies the whole of
as overexploited. It says the picture
is disturbing in Devanahalli, Doddaballapur, Nelamangala, Bangalore East
(Whitefield and adjoining areas). Bangalore
Apart from the CGWB, studies by the Department of Mines and Geology, Karnataka in its “Hydrology and quality of groundwater in and around
city - Review and excerpts from the report released in March 2011”, also show high
levels of chemicals in the ground water. Bangalore
The Karnataka study says fluoride has been a severe problem in many areas of Karnataka and country but never in Bangalore But, the last few years have seen fluoride entering groundwater in
though in a
small way. Most of the samples tested positive for fluoride was found at
Bellandur and Bidarahalli. Bangalore
The study conducted special testing for heavy metals in industrial areas.
Samples from the following areas showed high levels (much above drinking water standard) of contaminants:
Zinc: Gollahalli (Bommanahalli), Hosapalya (including CMC supply), Somasundarapalya (HSR 2nd Sector), ITI Layout (Hosapalya), Anu Polymers (
Reshma Dyeing Factory (Rajajinagar Industrial Area) Rajajinagar
Manganese: Peenya Industrial Area (11th Cross, 4th Phase), Hegganahalli (Srigandhanagar), Hosapalya (BBMP Nursery),
(Anu Polymers), Rajajinagar (Agrahara Dasarahalli), Rajajinagar
Industrial Town Old Madras Road Industrial Area
Chromium: 3rd Phase Peenya Industrial Area, Peenya 2nd Stage (Adrahalli Main Road), Peenya 2nd Stage (Andrahalli Main Road, Kaverinagar), Peenya 2nd Stage (Rajagopal Nagar), Hegganahalli (Srigandhanagar), Yelahanka New Town, Rajajinagar Industrial Town (Swadesh Industrial Supplier), Rajajinagar Industrial Town (Anu Polymers).
Former Additional Chief Secretary V Balasubramanian, has gone on record pointing out that the laboratory results of the Public Health Institute and the Department of Mines and Geology have so far indicated that 52 per cent of bore well water and 59 per cent of tap water in
is not potable. More shockingly, they
contain 8.4 per cent and 19 per cent Escherichia coli (E coli) bacteria
The Department of Mines report says that only 0.9 per cent of the groundwater in
is fit for consumption. Bangalore
Apart from contamination, the groundwater table has fallen to 45 meters in Mahadevapura. In HSR Layout, it is 37 meters and 26 meters in Jalahalli. It has fallen to 22 meters in Laggere (
Bengaluru East, Bengaluru North, Bengaluru South and Anekal (all in
urban district) and Devanahalli, Doddaballapur, Hoskote and Nelamangala (all in
Bangalore Rural district) have all reported falling ground water tables. Bangalore