UPSC MAINS 2019 : Flood Hazard Atlas

Flood Hazard Atlas

Topic : Flood Hazard Atlas

Topic in Syllabus : General Studies Paper 3: Ecology & Environment

 

Context:

Flood Hazard Atlas

Odisha has come out with a unique flood hazard atlas on the basis of historic flood inundation captured through satellite imagery over the period from 2001 to 2018.It is expected to help the State manage floods more efficiently.

 

Background:

  • Vast areas of the State are inundated when there is flooding every year in major rivers, namely, the Mahanadi, Brahmani, Baitarani, Subarnarekha and Rushikulya.
  • Some of the rivers like, the Vamsadhara and Budhabalanga, also cause flash floods due to instant run-off from their hilly catchments.
  • Damages due to floods are caused mainly by the Mahanadi, the Brahmani and the Baitarani, which have a common delta where floodwaters intermingle, and, when in spate simultaneously, wreak considerable havoc.
  • The entire coastal belt is prone to storm surges, which is usually accompanied by heavy rainfall, thus making the estuary region vulnerable to both storm surges and river flooding.

 

About the Atlas

  • The National Remote Sensing Centre (NRSC) of the Indian Space Research Organisation (ISRO), Hyderabad had taken the study on flood hazard zonation for Odisha.
  • A large number of satellite images acquired over 18 years (2001-2018) were used. All satellite data sets were analysed and flood layers were extracted. All the flood layers corresponding to a year are combined as one inundation layer, so that this layer represents the maximum flooded area in one year.”
  • All such combined flood layers for 18 years were integrated into flood hazard layer representing the observed flood-inundated areas with different frequencies. This layer was integrated with the digital database layers of Odisha The atlas would serve as a useful resource of information for policy makers, planners and civil society groups
  • Eight out of 30 districts such as Bhadrak, Kendrapara, Jagatsinghapur, Balasore, Puri, Jajpur, Khordha and Cuttack districts are more flood-affected districts. As high as 77% of Bhadrak and 70% of the Kendrapara district have been categorised as flood hazard.

A satellite image of flooding in Odisha

 

Benefits

  • Combined flood layers for 18 years were integrated into flood hazard layer representing the observed flood-inundated areas with different frequencies.
  • This layer was integrated with the digital database layers of Odisha.
  • The atlas would serve as a useful resource of information for policy makers, planners and civil society groups.
  • It will help to systematically plan flood control measures
  • It will help to control developmental activities on floodplains
  • It will help to carry out relief and rescue operation
  • It will also help to plan relief shelters and health centres

 

Sample Question:

Mention the flood management initiatives of government of India. Can we say India is well prepared for mitigating the ill effects of future floods? (250 words)

 


 

Flood hazard Atlas infograph