Corpn steps in, but drains pose a challenge

CHENNAI: Nothing ruins pleasant warm weather like a mosquito bite. From being a nuisance to carriers of deadly diseases, people are always looking for ways to eliminate these pests. With no predators posing a challenge in new stormwater drains, experts say the ideal solution will be to clear channels and ensure the free flow of water.

“Mosquitoes not only affect the quality of life but also pose a serious threat to life by infecting dengue and malaria. Anopheles mosquito causes malaria and is often found in freshwater; culex breeds in polluted water, and aedes mosquito breeds in the water stored in containers,” said a senior official with the Directorate of Public Health and Preventive Health.

“During the evening hours between 5 pm and 8 pm, mosquitoes that come from the open septic tank usually cause swelling but do not cause any disease. The main reason for an increase in mosquitoes is the depletion of mosquito-eating predators and the increase in drains. A study in 2010 taken up in Odisha confirmed that the Anopheline mosquito population increased by several folds due to the construction of an irrigation canal to increase in production of rice crops,” official sources told DT Next.

Stormwater drains are now a source of mosquitoes and cockroaches. The issue is that there is recent freshwater flow into the drains enabling the breeding of mosquitoes, but there is no other life in stormwater drains that can feed on mosquito larvae, admitted a civic official who closely monitors the vector control programme in Chengalpattu district.

Even developed nations like Singapore and Germany are finding it difficult to handle the mosquito menace.

Further, across the globe, the erratic weather conditions provide a conducive ambience for mosquitoes, the official said recalling that the mosquito control bio blocks for water bodies, ovitraps (mosquito traps), fumigations, and thermal devices to kill mosquitoes have produced minimal results helping the insects to go on a biting spree.

However, civic officials in Chennai and Chengalpattu districts are confident that the arrival of summer will decrease the mosquito population with their breeding areas getting dried up.

“Due to the blockage in the sewage system, the resultant drainage water stagnation in the area for days has led to an increase in mosquito menace. Also, the Cooum river stretch makes the situation worse. Residents are affected by vector-borne diseases such as dengue and malaria, especially among children,” said V Sathiabalan, a resident of Otteri.

The government mentioned that a mosquito net would be provided for every resident in the city, but failed to do so. Only specific areas were prioritised during the northeast monsoon last year. Sathiabalan added, “as the blockage in drainage pipes and leakage in the drinking water pipes, it led to contamination of drinking water. The local body officials use the road though they notice the sewage water stagnation, they go blind.”

The GCC has taken measures to control the mosquitoes through fogging, but it does not help to eradicate the insect. The mosquitoes on the road get inside the house once the workers carry out fogging. Public urge the city corporation to ensure the rainwater and drainage water are no longer stagnated and disinfect the stagnated water immediately to avoid mosquito breeding.

The residents’ welfare associations rue that they are unable to organise meetings and programmes in the evening hours. Due to a surge in the mosquito population, people hesitate to indulge in outdoor activities.

“The mosquitoes cause several health issues, people fall sick and hospitalised, and only then do the civic body authorities put bleaching powder, and fumigate the streets. But they are not bothered about the stagnated drainage water on the road,” said R Manoj Kumar, a resident of Ambattur.