Page 9 - Risk Management Bulletin April -June 2021

RMAI BULLETIN APRIL TO JUNE 2021

experience storm surge waves with a height of 10 to Y Well engineered structures with roofing systems
13 meters above the normal sea tide level. The height made of metal/ACC sheets/tiles/gable ends may
of the storm surge may increase by the height of suffer partial damages.
normal sea tide at the time of cyclone hitting the land Y Well engineered RCC structures with RCC roof may
above the sea water storm surge of 10 to 13 meters. withstand the forces of wind.
Y Non-symmetrical/fancy architectural structures
History of weather disturbances that
may suffer heavy damages.
hit the location Y Top heavy structures such as water tanks

The weather disturbances recorded by the Indian supported on single column, chimneys may
Meteorological Department (IMD) that hit West Bengal collapse.
zone since the year 1891 to 2019 are as follows :
Note - However in all the above structures, rolling
Weather Disturbance Number of shutters/doors/windows/glass parts/external walls of
Events glass in modern commercial buildings would get
Depressions / Deep Depressions 110 heavily damaged by wind forces/gale winds/flying
Cyclonic Storms 22 debris and also facilities installed in the open or on roof
such as solar heating/power systems/Towers etc. may
Severe Cyclonic Storms 20
get totally damaged and may have to be replaced by
Very Severe Cyclonic Storms 4
new ones after the cyclone.
Extreme Severe Cyclonic Storms 0
Super Cyclonic Storms 0 Building under Construction/Plants under
Erection:
Probability and intensity of cyclone
Y Building under construction/Plants under erection
hitting the location are yet not completed and hence do not have the
In the next 10 years the cyclones of following full strength and therefore may suffer heavy
intensities may hit the above West Bengal location : damages.
Cyclone Intensity Sign Wind Speed No. of Y Cranes which may collapse and other equipments
(IMD) (km/hr) Cyclones on site may suffer heavy damages.
Severe Cyclonic Storm SCS 88 to 117 1
(SCS) Disruption of services:
There will be disruption of electrical,
Very Severe Cyclonic VSCS 118 to 166 1
telecommunication, rail, road, water services due to
Storm (VSCS)
heavy damages by wind forces. There may not be any
Extremely Severe ESCS 167 to 221 0
local support available for repairs/reconstruction
Cyclonic Storm (ESCS)
services in this difficult times. It may take a month or
Super Severe Cyclonic SuCS 222 & Above 0 so to come back to normalcy, if not more.
Storm (SuCS)
Note: Super and Extremely Severe Cyclonic Storms are Flood Damages:
rare events and cannot be predicted accurately. Property/contents at the ground floor level and
basements would suffer substantial damages. The
Vulnerability extent of damage would depend on velocity, depth &
Wind and Flood Damages duration of the flood water at the site. Also the
susceptibility of the contents to water damage would
Structures that are completed and occupied :
be critical.
Y All non-engineered structures with roofing
systems made of metal/ACC sheets/tiles/gable Agriculture:
ends would be total loss. Y There are a large number coconut, betel nut etc.
Y RCC structures with RCC roof may suffer damages plantations and other fruit bearing trees e.g.
but may not collapse. mangoes etc. on the Indian coast and would suffer

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