Drone effect: Larval density in waterbodies down by 90 pc

According to a civic body report, the selected waterways had an overall pre-spray larval density of 5,259 and the same came down to 641 after drones were used to spray larvicide, which is an 89 per cent dip. 

The Corporation has decided to use advanced technology in mosquito control measures under the newly proposed Singara Chennai 2.0 project. Following this, the civic body conducted trial runs using drones with the help of the Avionics Department of Anna University recently. The trial was conducted in three phases. 

“One of the major public health issues encountered in the city is perennial mosquito menace. The principal reason for this menace is the 234 km length of five major and 31 minor waterbodies and canals traversing in the city limits. The major waterbodies, which were once carrying clean water, were polluted to such an extent that they have lost their self-cleaning capacity and are now serving as sewage carriers,” the report said. 

Of the total length of the waterways, the trial was conducted over 113.04 km. As per the reports, pre-spray larval density during the first phase trial was 2,975 and the density was reduced to 193 after the drones were used. Also, pre-spray larval density during the second and third trials were 1,170 and 1,114 and the same was reduced to 270 and 178 respectively. The report also pointed out a considerable reduction in the pupal density in the waterways. 

According to the report, the requirement of Mosquito Larvicide Oil (MLO) has been reduced while using drones. While using the conventional manual spray, the civic body used 4,520 litres of MLO for 113.04 km of waterways and the same was reduced to 4,351 litres while using the drones, which is 6 per cent lesser. 

An official said the report has been submitted to senior officials and once they approve the project, drones would be used across the city.