3. The Boundary of the Coast
The coastal region of Bangladesh is
situated along the Bay of Bengal and is
bordered by the ocean to the south. The
land boundary is formed by the Indian
states of West Bengal to the west and
Tripura to the north-east, and Myanmar
to the east. With a length of
approximately 720 kilometers, the coast
of Bangladesh presents a diverse range
of landscapes, from sandy beaches to
mangrove forests, estuaries, and deltaic
plains.
sssC
Figure 1 - Coastal Map of Bangladesh (Chowdhury, 2014)
4. Administrative Units
The coast of Bangladesh is divided into
several administrative units, including
districts, sub-districts (upazila), and
union councils.
At the district level, the coastal regions
of Bangladesh are divided into:
Chittagong, Cox's Bazar, Noakhali,
Laxmipur, Feni, Khulna, Bagerhat,
Satkhira, Patuakhali, Barguna, Pirojpur,
Jhalokati, Bhola, Barisal.
These administrative units play a crucial
role in the development and
management of the coastal regions,
including disaster management,
infrastructure development, and
conservation of the coastal ecosystems.
Figure 2 â Bangladesh coastal administrative
units (Sarwar, 2013)
5. Population and Density of The Coastal Area
According to the Bangladesh Bureau of Statistics
(BBS), the population of the coastal districts of
Bangladesh in 2011 was around 45 million,
representing about 30% of the total population of the
country.
The coastal zone of Bangladesh covers an area of
47,201 km2, 32% of the country, being the landmass
of 19 districts
Chittagong district is the most populous district with a
population of around 7.6 million people, followed by
Cox's Bazar district with a population of around 2.3
million people.
The population density of Chittagong is around 1,400
people per square kilometer, while the population
density of Cox's Bazar is around 920 people per
square kilometer.
Figure 3 â Aerial photograph of densely populated
Chittagong city
6. Division of the Coast of Bangladesh
Based on geomorphic features and tectonic condition, the coast of Bangladesh can be broadly
divided into major two regions â
The non deltaic coast is dominated by the tertiary anticlines and synclines parallel to the coast.
The deltaic coast is dominated by Padma-Jamuna-Meghna system and can further be subdivided into
two zones â
Coast of
Bangladesh
Deltaic
(Southern)
Non-deltaic
(Eastern)
Western
(Sundarban)
Central
(Meghna
Estuary)
7. Division of the Coast of Bangladesh
The Western Zone âThe western coastal region of
Bangladesh starts at the Harin-bhanga River and
ends at the Tetulia River, encompassing Greater
Khulna district, Patuakhali and several tidal rivers.
It features the Sundarbans mangrove forest and
important ports Mongla and Payra, but is vulnerable
to sea level rise, salinity intrusion, tidal flooding
and storm surges.
The Central Zone â The central coastal region
spans from the Tetulia River to the Feni River,
including the mouth of the Meghna River and
districts Patuakhali, Barisal, Bhola and Noakhali. It
experiences high sediment input, river bar
formation and bank erosion.
The Central
Zone
River
dominated
(western part
of Bhola)
Fluvio-tidal
dominated
(Middle part-
Bhola, Hatiya)
Tidal
dominated
(eastern part-
Sandwip) sub
zones
8. Division of the Coast of Bangladesh
The eastern zone â The Eastern
Zone includes the Feni River to
the Badar Mokam, Saint Martin
Island and a 145 km long sandy
beach from Cox's Bazar. It
features mainly antecedent rivers
like the Karnafuli and
developments in the Mirshari
and Matarbari area.
Figure 4 â Division of the coast of Bangladesh.
9. Morphology
Morphological features in the coastline of
Bangladesh:
Three distinct geo-morphological zones have
been identified in these coastlands: Ganges Tidal
Plain (western zone), Meghna Deltaic Plain
(central zone) and Chittagong Coastal Plain
(eastern zone) , as shown in Figure, A total of 19
districts constitute the exposed and interior coast
of Bangladesh.
Furthermore, the coastline of Bangladesh
encompasses a range of morphological features
beyond the predominant delta plain and tidal
flats, including mudflats, sandy beaches and
dunes, mangrove forests, estuaries, areas of low
elevation, backbarrier swamps, lagoons, and
coral reefs.
Figure 5 - Coastal zones of Bangladesh based on geo-
morphological features (Hasan, 2020)
10. Infrastructure-present and Proposed
The coast of Bangladesh has several infrastructure
developments in place, including ports and harbors for
trade and transportation.
Present Major Infrastructure -
Chittagong Port - The Chittagong Port is the
main seaport of Bangladesh. Located in Bangladesh's
port city of Chittagong and on the banks of
the Karnaphuli River.
Mongla Port - The Port of Mongla is a link sea port,
located at Mongla Upazila, Khulna Division,
Bangladesh. It is the second largest and second busiest
seaport of Bangladesh.
Cox's Bazar International Airport - is a domestic
airport in the resort town of Cox's Bazar, Bangladesh.
Payra Thermal Power plant - Upon completion it is the
largest power plant in Bangladesh. Inaugurated by PM
Sheikh Hasina on 21March of 2022
Karnaphuli Tunnel - First underwater tunnel in
South Asian region, part of Dhaka-Chittagong-
Cox's Bazaar highway network.
Payra Sea Port - Originally planned as a deep
sea port, now due to dredging costs, project
has been changed to a regular port.
Figure 6 â Chittagong sea port
11. Infrastructure-present and Proposed
Proposed Infrastructure â
Bangladesh Navy frigate program - Six stealth
guided missile frigates are expected to be
constructed at Chittagong Dry Dock Limited for
Bangladesh Navy and launched into service in
2030.
BNS Sheikh Hasina Submarine Base - A full-
fledged submarine base of the Bangladesh Navy
being constructed with technical assistance from
China, has been completed 60%
Matarbari Power Plant - Some 30% of
construction work on the 1200MW Matarbari
coal-fired power plant was completed and has a
target to complete the most expensive scheme by
June 2023
Chittagong Metro Rail - Pending approval from
Road Transport and Highways Division.
Mirsarai Economic Zone (Largest Economic
zone in Asia) - Mirsarai Economic Zone is an
industrial economic zone currently under
development in Mirsarai Upazila, Chittagong.
Matarbari Deep Sea Port - This will be the first
deep sea port of Bangladesh. Projected
completion in 2026.
Figure 7 â Matarbari deep sea port
12. Problem or Hazards
The coastal areas of Bangladesh are
highly vulnerable to natural and man-
made hazards and disasters like coastal
flooding, cyclones, storm surges,
erosion, salinity, arsenic contamination,
and pollution (Parvin et al., 2008)
Cyclones: Tropical cyclone Sidr hit
Bangladesh in November 2007 causing
widespread damage, with estimated
3,447 deaths and some estimates
reaching. The storm was one of the
worst 15,000 natural disasters in
Bangladesh's history. Sidr formed in
the central Bay of Bengal, and quickly
strengthened to reach peak 1-minute
sustained winds of 260 km/h
Figure 8 - Cyclone Sidr making landfall in Bangladesh (UWM, 2007)
13. Problem or Hazards
Coastal Flooding: Coastal flooding in
Bangladesh is frequent and severe,
caused by its low-lying coastal region,
natural disasters and rising sea levels
from climate change, resulting in damage
to infrastructure and displacement of
communities.
Storm Surges: Storm surges are a major
cause of coastal flooding in Bangladesh,
caused by high winds, low pressure, and
high tides, especially in the Bay of
Bengal during monsoon season. They
cause damage to homes, crops, and
infrastructure, and displace thousands of
people. Figure 9 â Animation of Storm Surges to Shallow and Steep Continental
shelf
14. Problem or Hazards
Pollution: Coastal areas, including
Bangladesh, face high levels of pollution
from human populations and industries,
including agricultural runoff, industrial waste,
sewage discharge, and plastic waste.
Arsenic: Arsenic contamination is a major
problem in coastal Bangladesh, caused by the
region's high levels of naturally occurring
arsenic and over-extraction of groundwater,
which leads to pumping of arsenic-
contaminated water to the surface
Salt Water Intrusion: Salt water intrusion is
a common issue in coastal Bangladesh, where
over-extraction of groundwater has caused
seawater to mix with freshwater aquifers,
making the water undrinkable and affecting
agriculture.
This is due to factors like rising sea levels,
declining groundwater levels, and changes in land
use.
Figure 10 â Animation of salt water intrusion
15. Problem or Hazards
Erosion: Coastal erosion affects Bangladesh's coast,
which is flat and low-lying on the Bay of Bengal. It is
caused by natural processes, human activities, and sea
level rise. The impacts include land and infrastructure
loss, community displacement, and ecosystem
damage. Mitigating these impacts requires restoring
mangroves, improving coastal management, and
reducing greenhouse gas emissions.
Seal Level Rise: Sea level rise due to global warming
is a major issue for Bangladesh's coast, causing
coastal erosion, flooding, saltwater intrusion,
mangrove loss, and community displacement.
Mitigation can be achieved by reducing greenhouse
gas emissions and implementing measures such as
sea walls and mangrove restoration.
Figure 11 â Sea Level Rise and effects on
Bangladeshâs districts
16. Management
Storm surges and Cyclones Hazard
Management:
Bangladesh's coastal areas face significant
risk from storm surges and cyclones. To
manage these hazards, the following steps are
typically taken:
⢠Early warning system
⢠Evacuation plans
⢠Sea walls
⢠Mangrove and coastal vegetation
reforestation
⢠Building codes and land-use regulations
⢠Community, government, and non-
government capacity building
In addition to the measures listed, other popular
management systems for coastal hazards
include â
⢠Numerical modeling,
⢠IoT (Internet of Things),
⢠Satellite
Figure 12 - The Afsluitdijk Sea Wall in Holand
17. Management
Numerical Modelling: Numerical modeling
predicts cyclone path and intensity by
simulating physical processes. It uses
mathematical equations to model atmosphere,
ocean, and land behavior and is important for
predicting cyclone impacts
Figure 13 - Storm surge (SIDR) forecasted on 14th Nov, 2007
by Numerical Model (Mashriqui, 2007)
IoT (Internet of Things): An IoT system improves
storm surge and cyclone management by providing
real-time monitoring, early warnings, damage
assessment with drones, and integrating with
disaster plans.
Figure 14 â Observing system to improve hurricane
prediction
18. Management
Satellites play an important role in managing coastal
surges and other ocean-related hazards. Here are a few
ways satellites can assist in managing coastal surges:
⢠Monitoring sea level changes
⢠Tracking storms and hurricanes
⢠Mapping coastal erosion
⢠Supporting decision making
Some common types of satellites used for this purpose
include:
⢠Geostationary Operational Environmental Satellites
(GOES)
⢠Polar Operational Environmental Satellites (POES)
⢠Synthetic Aperture Radar (SAR) Satellites
⢠Microwave Imagers
⢠Altimeter Satellites
Since this is a GOES satellite, itâs in geostationary orbit,
and weâre able to track clouds. When you just look at an
image or look at an animation, you see the clouds
moving, you see the hurricane spinning.
Figure 15 - 2020 Atlantic Hurricane Season GOES-16
Infrared Satellite Imagery Animation (NASA, 2020)
19. Management
Management of coastal erosion:
⢠Shoreline Hardening
⢠Beach Nourishment
⢠Dune Restoration
⢠Relocation and Retreat
⢠Land Use Management
Management of coastal pollution:
⢠Waste Management
⢠Sewage Treatment
⢠Industrial Pollution Control
⢠Agricultural Runoff Management
⢠Storm-water Management
⢠Maritime Transport Regulations
Management of Salt water intrusion:
⢠Implementing sustainable groundwater
policies to reduce saltwater intrusion
⢠Recharging groundwater aquifers
⢠Diverting surface water into the aquifer
⢠Desalinating seawater for freshwater use
⢠Constructing physical barriers (e.g. tidal
gates)
Figure 16 â Plastic pollution in sea beach
20. Coastal Policy
United Nations Convention on the Law of the Sea
(UNCLOS) 1982, also known as Law of the
Sea divides marine areas into five main zones namely-
Internal Waters, Territorial Sea, Contiguous Zone,
Exclusive Economic Zone (EEZ) and the High Seas.
Internal Waters: Internal waters are
under a coastal state's full sovereignty,
with no right of innocent passage.
They are located on the landward side
of the baseline used to measure the
breadth of the territorial sea.
Territorial Sea: The territorial sea
extends seaward up to 12 nautical
miles (nm) from its baselines. The
coastal states have sovereignty and
jurisdiction over the territorial
sea. These rights extend not only on
the surface but also to the seabed,
subsoil, and even airspace.
Figure 17 â UNCLOS Maritime Zones
21. Coastal Policy
Contiguous Zone: The contiguous zone extends 24
nm from the baselines and is between the territorial
sea and high seas. The coastal state can enforce
fiscal, immigration, health, and customs laws within
its territory and territorial sea. The contiguous zone
only grants jurisdiction over the ocean's surface and
floor, not over air or space.
Exclusive Economic Zone (EEZ): Each coastal
State may claim an EEZ beyond and adjacent to its
territorial sea that extends seaward up to 200 nm
from its baselines Within its EEZ, a coastal state has:
Sovereign rights for the purpose of exploring,
exploiting, conserving and managing natural
resources, whether living or nonliving, of the seabed
and subsoil.
High Seas: The ocean surface and the
water column beyond the EEZ are
referred to as the high seas. It is
considered as âthe common heritage of all
mankindâ and is beyond any national
jurisdiction.
Bangladeshâs Law for Maritime Zones:
Bangladesh's coastal marine areas in the
Bay of Bengal are divided into three
zones under UNCLOS-III: territorial
waters (12 nm), an exclusive economic
zone (EEZ, 200 nm), and a continental
shelf (350 nm from Bangladesh baseline).
Its total sea area under UNCLOS-III is
2.07 million km², 1.4 times greater than its
land area.
22. Conclusion
In conclusion, the coastal zone of Bangladesh faces a range of challenges, including coastal flooding,
storm surges, coastal erosion, pollution, salt water intrusion, and arsenic contamination. These
challenges pose significant threats to the environment, human health, and the livelihoods of the
people living in the coastal areas. The Bangladeshi government and international organizations are
taking steps to address these issues, but there is still much work to be done to ensure a sustainable
and resilient future for the country's coastal communities. It is essential that all stakeholders,
including the government, NGOs, local communities, and the private sector, work together to
implement effective solutions that will ensure the long-term health and stability of Bangladesh's
coastal zone.
23. Reference
[1] Belal. A.S.M (n.d.) Bangladesh Institute of Peace and Security Studies. Maritime Boundary of Bangladesh: Is Our
Sea Lost? Retrieved from https://www.files.ethz.ch/isn/164392/mb_bd.pdf
[2] ChatGPT: Optimizing Language Models for Dialogue Retrieved from https://chat.openai.com/chat
[3] Chowdhury. S. R (2014, 11 January). Coastal Zone of Bangladesh (Map). Retrieved from
http://creativecommons.org/licenses/by-nc/4.0/
[4] Matin, Naila & Hasan, G M Jahid & Ahmad, Myisha. (2020). Regional Trends of Sea Level Rise along the Coast of
Bangladesh. International Journal of Engineering Sciences. 13. 10.36224/ijes.130102.
[5] Parvin, Gulsan & Takahashi, Fumito & Shaw, Rajib. (2008). Coastal Hazards and Community-coping Methods in
Bangladesh. Journal of Coastal Conservation. 12. 181-193. 10.1007/s11852-009-0044-0.
[6] Sarwar, Md Golam & Islam, Aminul. (2013). Multi Hazard Vulnerabilities of the Coastal Land of Bangladesh.
10.1007/978-4-431-54249-0_8.
[7] Wikipedia contributors. (2021, May 22). Cyclone Sidr. In Wikipedia, The Free Encyclopedia. Retrieved from
https://en.wikipedia.org/wiki/Cyclone_Sidr
