Kolkata on cyclone’s edge, takes guard – Times of India

KOLKATA: If the high velocity wind had wreaked havoc in Kolkata a year ago when cyclone Amphan smashed into the city, it is heavy rain brought by cyclone Yaas, coupled with year’s highest tide Sarasari Baan, that threaten to inundate large parts of Kolkata.
While the heavy rain forecast is expected to be much more than the maximum 10mm per hour that the city’s drainage system can tackle, the timing of the Sarasari Baan on Buddha Purnima means that for several hours, the drainage pumping stations will be unable to pump out water into the Hooghly on high tide.

“Large parts of north, central and south Kolkata are likely to be inundated till the lock gates along the Hooghly can be opened to drain out the storm water,” a civic drainage department official said.
Though the civic body has adopted several measures to combat severe waterlogging in view of the heavy to very heavy rainfall that the cyclone may bring with it on Wednesday, none of these measures will be effective till the tide turns.
On Tuesday, the high tide set in at12.43pm with the maximum tide surge of 16.7ft. Consequently, the lock gates were shut from 11am to 3pm. With KMC and irrigation department set to keep the gates shut from 11.30am to 4pm on Wednesday, roughly the same time when heavy rain is predicted to lash Kolkata, flooding is inevitable.
“On Wednesday, the maximum tide surge will be 17.3ft, which is 3-4ft above the normal height of a tide. As a precautionary measure, we will shut the lock gates for four-and-a-half hours to prevent water from reverse flow into the city. If it pours during this period, inundation is inevitable. We will have no option but wait for the tide to subside to then start the heavy-duty pumps to drain out storm water,” the official said.
Operating the pumps when the lock gates are shut will trigger a backflow and render the pumps defunct.
A KMC drainage department official posted in a central Kolkata office said he was particularly worried over inundation of large areas of Rabindra Sarani (Chitpore), Bagbazar, Burrabazar, Netaji Subhas Road, Strand Road, BBD Bag, Bhowanipore, Kalighat, Chetla, Alipore, Kidderpore and NSC Bose Road (Tollygunge), among others, because of their proximity to either the Hooghly or the Tolly’s Nullah.
With the electrocution of a youth in a waterlogged BBD Bag street still fresh in people’s minds, the civic brass is not taking chances and are trying to evacuate hawkers and pavement dwellers from BBD Bag, Strand Road, Burrabazar and other areas located closer to the river. “ We are keeping submersible pumps ready in case we need them to flush out storm water from low-lying areas after lock gates are opened,” a KMC sewerage and drainage department official said.