Presence of E.coli bacteria has reached dangerous levels in groundwater

According to a survey, faecal intrusion has made groundwater in the district unfit for human consumption. A sample survey of well water conducted by the District Suchitwa Mission (DSM) reveals that presence of E.coli bacteria has reached dangerous levels in groundwater.

DSM collected 15 samples of well water from as many local bodies in rural and urban areas last week. Of the 15 only one sample had ‘satisfactory’ results after they were tested at the Regional Analytical Lab, Kakkanad.

Drinking water must be free of any trace of E. coli, a type of faecal coliform bacteria found in the intestines of animals and humans.

A study of the 15 samples showed that the count of E.coli ranged from hundred to thousands. In one sample, the count was as high as 2,400, effectively reducing the water to waste. The laboratory report recommended that most of the wells sampled be drained and disinfected. Fresh water should then be disinfected using bleaching powder in the proportion of 10 mg per 4,000 litres. Ideally, this disinfection process should be done every fortnight.

“In the light of the findings, we are planning to go for a massive sample collection across the district. The idea is to collect four to five samples from each local body depending on the topography of the area,” P.K. Alexander, district coordinator, DSM, told The Hindu.

The testing of samples will be done with funds allotted to the Suchitwa Mission. Though the public has been advised to test water samples at frequent intervals, it may not be practical as tests cost about Rs.1,000, Mr. Alexander said.

P.S. Hariharan, assistant coordinator, said given the high costs of testing, local bodies had to fund testing of water samples.

He said the survey revealed that in rural areas single unscientifically created pits replaced septic tanks.

“Pits should not extend beyond the maximum depth of 1.20 metres in areas with laterite soil. In sandy areas such as coastal regions it should be within 30 cm to prevent the pit from coming into contact with groundwater. But it was found that the pits were drawn at the maximum depth possible in many areas,” he said.

Mr. Hariharan said the septic tanks were also found to be constructed in faulty manner.

Septic tanks are supposed to facilitate sucking out its content periodically to allow cleaning. A majority of the septic tanks were also found permanently sealed. The DSM has planned to launch a massive awareness campaign on septage management.