The city civic authorities will soon deploy eight more mechanical sweepers to suck up dust — responsible for the haze and smog — and small trash from the roads.

One mechanical sweeper, procured two-and-a-half-years ago, is now in operation on the EM Bypass and Bridge No. 4, and in Gariahat.

The new sweepers will be pressed into service in November — on AJC Bose Road, APC Road, Shakespeare Sarani, Park Street, CR Avenue, Bhupen Bose Avenue, Grey Street, Beadon Street, MG Road, BB Ganguly Street, Rafi Ahmed Kidwai Road and Free School Street, and also in New Market and other pockets.

Each device can sweep up to 40 km of road a day. The Calcutta Municipal Corporation now deploys over 10,000 sweepers, each cleaning hardly 250 metres of road daily.

Civic chief engineer (conservancy) Arun Sarkar said the nine mechanical sweepers will suck up 200 tonnes of dust from the roads.

“The concentration of particulate matter in city air is rising steadily. Though roads are swept daily and trash removed, the dust remains,” said municipal commissioner Alapan Bandyopadhyay.

“The dust has been contributing to the frequent occurrence of morning haze and evening smog, and also causing respiratory disorders. Once the mechanical sweepers are deployed, the concentration of dust will be considerably reduced,” he added.

Mayoral council member (conservancy) Chandana Ghosh Dastidar said the lone mechanical sweeper now in use collects 24 tonnes of dust on the Bypass daily. “That’s the reason why the trees along the thoroughfare are so much greener now,” she added.

The civic authorities are procuring the fleet of eight mechanical sweepers under the Asian Development Bank-funded Calcutta Environment Improvement Project.