Month’s rain in 4 hours, high tide worsens floods resulting to widespread waterlogging
Telegraph | 24 September 2025Officials and engineers from the Kolkata Municipal Corporation (KMC) attributed the flooding to this rare combination of intense rain, tidal conditions, and infrastructural disruptions.
On Tuesday evening, several major arterial roads remained submerged, including Shakespeare Sarani, Sarat Bose Road, Syed Amir Ali Avenue, Colootala Street, Camac Street, Cathedral Road, AJC Bose Road, and stretches of Rashbehari Avenue.
Early on Tuesday morning, hardly any road in the city was free of waterlogging. The scale and severity far exceeded the usual flooding seen after heavy rains.
Hip-deep water flooded many narrower lanes in neighbourhoods like Kasba, Ballygunge, Jadavpur, Santoshpur, Mukundapur, and Bhowanipore. In Gariahat, water levels breached the kerbside guardrails around 11am.
Residents in Salt Lake expressed shock, saying they had never witnessed flooding of this magnitude. An office worker commuting to Sector V recounted how it took over an hour to reach work from EM Bypass.
A Nabadiganta Industrial Township Authority (NDITA) official pointed to damage caused by Metro railway construction as a factor behind Sector V’s waterlogging.
“The volume of rain between midnight on Monday and 4am on Tuesday equalled the city’s typical monthly monsoon rainfall. Such intense rain in a short span inevitably causes waterlogging. Unlike usual monsoon days, where rainfall varies across neighbourhoods, this time the heavy rain was city-wide,” a KMC official explained.
The Met office recorded 252mm of rain in five hours, with 185mm coming down between 2.30am and 5.30am. Salt Lake received over 220mm during this period.
According to KMC data, Garia was the wettest with 332mm, followed by Jodhpur Park at 285mm, Ballygunge at 264mm, Ultadanga at 207mm, and Maniktala at 169mm.
Mayor Firhad Hakim said: “Calcutta has not witnessed such abnormal rain in such a short time before. Our pumping stations operated at full capacity to drain the water.”
Adding to the crisis were two four-hour intervals between Monday midnight and Tuesday evening when sluice gates along the Hooghly had to be closed due to high tide, preventing drainage into the river.
An official said that the sluice gates remained shut from midnight to 4am (coinciding with peak rainfall), and again between noon and 4pm.
These gates close roughly two hours before and two hours after the peak of the high tide to prevent Hooghly’s waters from entering the city’s drainage network, which would worsen flooding.
Rainwater in Calcutta drains west into the Hooghly and east into the Bidyadhari through a network of canals.
KMC officials explained that opening sluice gates normally speeds drainage into the Hooghly. However, draining water eastward depends on pumping station efficiency and the canal system.
“On Tuesday, the canals were already full, slowing the drainage process,” an official said.
The Salt Lake Bypass and nearby Sector V areas were waterlogged, primarily due to damage to a major drainage line caused by ongoing Metro rail construction. “Stretches of drainage lines between Technopolis and Pumping Station No. 5 near AL BL Crossing, as well as near Wipro, were damaged. Repairs or diversion couldn’t be done because the Metro work on that stretch is incomplete,” said an NDITA official.
The Rail Vikas Nigam Limited, responsible for the Metro construction, did not respond to calls.
