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Disaster Management - Flood

Floods : 

Whenever the magnitude of water flow exceeds the carrying capacity of the channel within its banks, the excess of water over flows on the surroundings causes floods.

Causes of floods :


1. Heavy rain, rainfall during cyclone causes floods. 

2. Sudden snow melt also raises the quantity of water in streams and causes flood. 

3. Reduction in the carrying capacity of the channels, due to accumulation of sediments causes floods. 

4. Sudden and excess release of  impounded water behind dams. 

5. Human activities like construction of roads, buildings and parking space, that covers the earth's surface, prevents infiltration of water into the soil and speeds up the run off.

6. Clearing of forests for agriculture has also increased severity of floods.

Effects Of Floods :

1.Floods cause heavy suffering to people living in low lying areas because the houses and the properties are washed away.

2.Floods damage standing crops and livestock. 

3.Floods cause a great economic loss and health related problems due to widespread contamination.

Flood Management : 

Flood Management involves the following activities :

1. Encroachment of flood ways should be banned.

2. Building walls prevent spilling out the flood water over flood plains.'

3. Diverting excess water through channels or canals to areas like lake, rivers, etc., where water is not sufficient.\

4. Build check-dams on small streams, move building off the flood plains. 

5. Restore wetlands, replace ground cover on water-course.

6.Instead of raising buildings on flood plain, it can be used for wildlife habitat, parks, recreational areas, which are not susceptible to flood damage.

7. River - Networking in the country also reduce flood.

8. Satellite pictures of pre-flood, flood and post flood with other information contribute to the flood management process.

9. Optical and microwave data from IRS is also used for flood management

10. Flood forecasts and flood warning are also given by the central water commission.

11. Reduction of runoff by increasing infiltration through appropriate afforestation.

 

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