High coliform content in Vembanad Lake

Bacteria found in six rivers that drain into lake

Published - November 23, 2019 11:14 pm IST - Alappuzha

The presence of high levels of coliform bacteria in Vembanad Lake, especially at Punnamada, a houseboat boarding point, has put the houseboat operations in the district under the scanner.

As per a recent report of the Alappuzha unit of the Kerala State Pollution Control Board (KSPCB), the lake’s water quality is declining. An analysis of water samples collected from 11 points in the waterbody in Alappuzha has revealed the presence of coliform bacteria exceeding permissible limits.

The water contamination, especially caused by faecal coliform, was particularly high at Punnamada. The total coliform count in water collected from Punnamada was 8,000/100 ml in April 2019, against the permissible limit of 500 Most Probable Number (MPN)/100 ml. It stood at 4,000/100 ml and 2,000/100 ml in May and June. The report says that the presence of coliform bacteria was found in six rivers that drain into the lake.

Houseboats discharge

According to PCB officials, houseboats discharging waste water directly into the waterbody in the absence of proper waste management systems is taking a heavy toll on the Vembanad lake ecosystem. A sewage treatment plant operated by the District Tourism Promotion Council for houseboats registered in Alappuzha at H- Block (Kunnumma) remains dysfunctional for the past six months.

“Vembanad’s water is highly polluted. Apart from rampant dumping of septage generated in Alappuzha and nearby districts in the lake, majority of houseboats operating in the district are discharging untreated septic waste in it. The water in different parts of the lake has become unsuitable even for bathing purpose,” said an official.

For bathing, coliform level should be 500 MPN/100 ml or less.

T.D. Jojo, project coordinator, Ashoka Trust for Research in Ecology and the Environment (ATREE), suggested setting up more sewage treatment plants.

Treatment plants

“It is a fact that microbial contamination is high in the southern part of Vembanad Lake. Given the high number of houseboats, the facility at H Block is insufficient. To prevent faecal contamination of the lake by houseboats, there is a need to construct 7 or 8 waste treatments plants. This will help houseboats flush clean its toilets without dumping waste water into the lake,” Mr. Jojo told The Hindu .

0 / 0
Sign in to unlock member-only benefits!
  • Access 10 free stories every month
  • Save stories to read later
  • Access to comment on every story
  • Sign-up/manage your newsletter subscriptions with a single click
  • Get notified by email for early access to discounts & offers on our products
Sign in


Comments have to be in English, and in full sentences. They cannot be abusive or personal. Please abide by our community guidelines for posting your comments.

We have migrated to a new commenting platform. If you are already a registered user of The Hindu and logged in, you may continue to engage with our articles. If you do not have an account please register and login to post comments. Users can access their older comments by logging into their accounts on Vuukle.