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Coastal Flooding: Bangladesh (Background (46% of population lives less…
Coastal Flooding: Bangladesh
Background
46% of population lives less than 10m above sea level
lies on flood plain of 3 major rivers and empty into the \bay of Bengal along with 54 smaller rivers
areas flood annually due to snow melt from the Himalayas, along with monsoon rains and high tides
world's most densely populated country - 169 million
coastal flooding occurs March - May
Causes of Coastal Flooding
SUBSIDENCE
some estuarine islands sunk as much as 1.5m in the last 50 years
clearance and drainage of over 50 islands in Ganges-Brahmaputra river delta
used to grow rice in order to feed large population
1960s and 70s - large earth embankments built as protection against tidal and storm-surge inundations
human action prevented natural deposition of sediment that used build the height of the island
REMOVING VEGETATION
mangroves provide protection against and shelter against extreme weather events
mangroves absorb and disperse tidal surges
Cyclone Sidr 2007 - Sundarbans forest reduced effects
71% of mangrove-forested coastline retreating by 200m a year
erosion, rising sea levels and deliberate removal
Management Strategies
EMBANKMENTS
4000km of coastal embankments have been built
30 million live on polders (land enclosed by embankments)
2014 - planned to upgrade 600km of embankments using $400 million from the World Bank
John Pethick suggest moving the embankments further inland, however residents do not want to give up land due to rising sea levels
'channeling effect'
MANGROVES
villages with 4km or more of mangroves recorded no deaths
NGO Wetlands International working to reverse effects of mangrove destruction
assisting villagers to plant mangroves along the coasts and banks of tidal rivers