Chennai water crisis: One in 5 taps serves contaminated water

originally posted on January 10, 2017


CHENNAI: It isn’t just water scarcity that will keep officials on their toes this summer, but contamination too. And they could well begin their search for germs in the tanks of schools.

Routine lab tests on water supplied in state facilities by King Institute of Preventive Medicine found that more than half the samples collected from schools were contaminated — the highest compared to other sources in the public domain. This was closely followed by the water collected from public fountains in the railways where around 59% of the samples were found non-potable.

Public health experts say the contamination in these place could be because of poor sanitation at the end point of supply. “This is more prevalent in railway stations. The pollution in schools could be because institutions rarely take the effort to clean overhead tanks and sumps, which also need to be closed,” said former corporation health officer Dr P Kugananthan.

The samples were collected by health inspectors attached to the chief water analysis laboratory in Guindy from seven districts over the course of a year. Close to 70% of the samples were collected from Chennai.

Inspectors also labelled as “bad” around 25% of the samples collected from government hospitals. For example, all the seven samplings taken from the government ophthalmic hospital were found to be non-potable. Health inspectors also conducted a camp in the city post cyclone Vardah and found contamination in the water supplied by metrowater in Tondiarpet, New Washermenpet, Valsaravakkma and Mandaveli.

Although the lab did not specify the pollutants, officials in the directorate of public health and corporation — which also has a water testing lab — say bacteriological contamination caused by animal and human faeces is the most common cause of pollution in the city. Even a simple test on tap water, they say, shows high content of bacteria like E.coli and coliform. Nearly one tenth of the city households still drink water directly from taps.
According to a WHO classification, about 40% of all diseases – including diarrhea, typhoid, dysentery and cholera– are water-borne.

The contamination doesn’t just vary from one public domain to another. It varies in different areas too. A recent survey on the quality of water by Chennai Corporation found that contamination was highest in North Chennai, with at least 250 of the 450 samples in metrowater pipes found “unfit to drink” as they contained disease-causing germs, toxic sediments and human and animal faeces.

Broken pipes, overflowing sewage, open defecation, corroded pipelines and inadequate maintenance of old pipe network are the primary causes of contamination. The average age of underground pipes is 50 years. Rust has gnawed holes in the pipes that snake through the city’s filthy underbelly, facilitating seepage of sewage and muck. However, the public health department said the most common point of contamination observed by its field inspectors is pollution at the distribution end. “Ideally a tap or a sump is supposed to be above ground level. But people keep it low in open soil pits hoping to get more water. The environment around results in the water being polluted,” said K Kolandaswamy, director of public health and preventive medicine. He said while metrowater had the facilities in place to treat water, it gets polluted en route because residents illegally fiddle with the pipelines.

The government, he said, isn’t just testing the quality of water but is also undertaking a chlorination drive. “If we detect pollution at some point, we communicate it to the respective institute and help them find the source,” he said.

Public health experts said monitoring the quality of water is essential in the coming months with Chennai metrowater cutting supply because of dwindling resources. “This will force residents to source water from sources that don’t come under the official radar – a ditch with water or a well that has been in disuse for long,” said former director of public health S Elango.


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