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| ‘Not a single water sample in Karachi found potable’ |
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Urbanisation posing threat to water sources
Wednesday, April 01, 2009
By Aroosa Masroor
Karachi
Of the 2,000 water samples collected over a period of 20 years from different parts of the city, none have proved to be fit for human consumption, revealed a detailed study conducted by Prof Dr Syed Jamil Hasan Kazmi and Ihsanullah Khattak of Department of Geography, University of Karachi (KU).
During an interview with The News, Dr Kazmi disclosed that eutrophication (a pollution problem) in Haleji Lake and Keenjhar Lake – one of the major sources of water for Karachi – has led to increased contamination of water that is now unfit for drinking. Eutrophication is an increase in chemical nutrients, compounds containing nitrogen or phosphorus that may occur in land or water and results in lack of oxygen and severe reductions in water quality, fish and other animal populations. Due to the release of untreated sewage effluent and run-off from fertilizers into natural waters, water from what were once known as the ‘fresh water lakes’ can no longer be consumed.
The study was conducted with the assistance of researchers from the Department of Geology and the quality of water was examined from diverse areas stretching from Gulshan to Gadap Town. “Among other areas were Federal B. Area, North Karachi and squatter settlements,” informed Dr Kazmi. Samples from the Hub Dam, which supplies around 20 to 25 per cent water to the city, were also found to be contaminated.
He explained that the quality of water in the Hub Dam and other lakes were examined through the standard Most Potable Number Technique (MPN) method. However, water from all the samples failed to meet the WHO (World Health Organisation) guidelines for bacteriological quality of drinking water, which means that the most important water resources are grossly polluted with organisms of public health importance. “This poses a potential threat to the people consuming water from the area,” added Dr Kazmi.
For the study, water samples were collected in pre-sterilised bottles for the bacteriological analysis of Total Coliforms Count (TCC), Total Faecal Coliforms Count (TFC) and Total Faecal Streptococci (TFS) and sent to the Institute of Environmental Studies at KU for examination. “All the samples were found to be contaminated with these organisms, which are of public health importance and a continuous source of ailment in the local people,” said the study.
In the case of Gadap Town, the research team’s found that the highest recorded amount of nitrates in the water samples was only about 0.9mg per litre whereas according to the WHO recommended standards the amount of nitrates should be about 50mg per litre. “This deficiency of a dangerous extent further highlights how our drinking water is grossly polluted.”
The Karachi Water and Sewerage Board (KWSB) however claim that the water it supplies is free from bacterial contaminants, despite findings by NGOs and other agencies like the Institute of Environmental Studies prove otherwise. When questioned, Dr Kazmi explained that the discrepancy could be due to the sample collection from different sources and because sampling techniques and method of analysis differ. “The KWSB infrastructure is also quite old which is why water in the distribution pipelines often gets contaminated,” said Dr Kazmi, adding that he was shocked at the government’s indifference towards the issue. “Urbanisation and environmental changes are a major threat to water resources. Unless drinking water supplies become free from contamination, there is little hope of controlling communicable diseases in the population. The sooner we realise the more deaths can be prevented.”
Samples collected from various
sources of water supply to Karachi
S.No. Sample Tag Location TCC TFC TFS Remarks
1 S1 Hum Dam 900 - - UNFHC
2 S2 Zaidi Farm 400 - - UNFHC
3 S3 NA 900 - - UNFHC
4 S4 Lasbela Canal 1500 - - UNFHC
1 S1 Hub Reservoir 4300 9 - UNFHC
2 S2 Hub Reservoir 1500 <3 - UNFHC
3 S3 Hub Reservoir 2300 21 - UNFHC
4 S4 Hub Reservoir 150 240 - UNFHC
5 S5 Hub Reservoir 28 28 - UNFHC
6 S6 Hub Reservoir 900 23 - UNFHC
7 S7 Hub Reservoir 4000 23 - UNFHC
8 S8 Hub Reservoir 2200 19 - UNFHC
1 S1 Khar 2400 1100 <3 UNFHC
2 S2 Khar Centre 2400 1100 <3 UNFHC
3 S3 KNP 2400 1100 <3 UNFHC
4 S4 Haji Imam Buksh 460 <3 <3 UNFHC
5 S5 Goth Rabo 2400 1100 <3 UNFHC
6 S6 Hum Dam 43 <3 <3 UNFHC
7 S7 Karachi Canal 240 <3 <3 UNFHC
8 S8 Hum Dam Colony 240 43 <3 UNFHC
9 S9 Lasbela Canal 240 150 <3 UNFHC
10 S10 Karachi Canal 150 43 <3 UNFHC
TCC Total Coliforms Count TFC Total Faecal Coliforms Count
TFS Total Faecal Streptococci UNFHC Unfit for Human Consumption
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ISSN 1563-9479 
