Bihar’s topography is marked by a number of perennial and non-perennial rivers of which, those originating from Nepal are known to carry high sediment loads that are then deposited on the plains of Bihar. A majority of the rainfall in this region is concentrated in the 3 months of monsoon during which the flow of rivers increases up to 50 times causing floods in Bihar. According to the Bihar Government’s Flood Management Information Systems Cell, floods of Bihar can be divided into 4 categories namely:

Class I: Flash floods– floods occurring due to rainfall in Nepal, lead time is short (8 hours), receding of flood waters is fast;

Class II: River floods– lead time 24 hours, receding of flood waters is 1 week or more;

Class III: Drainage congestion in river confluence- lead time more than 24 hours, lasting full monsoon season (i.e. receding of flood water takes 3 months).

Class IV: Permanent water logged area.

As such, 73.63% of the geographical area of North Bihar is considered to be prone to floods. Out of 38 districts, 28 districts get flooded (of which 15 districts are worst affected) causing huge loss of property, lives, farmlands and infrastructure. During the 2008 Kosi floods, over 350,000 acres of paddy, 18,000 acres of maize and 240,000 acres of other crops were adversely affected, impacting close to 500,000 farmers.

DO’S AND DON’TS

Do’s:-

• Tune to your local radio for warnings and advice.
• Move to higher ground.
• Move vehicles, equipments, chemicals, old persons, children, pregnant women, etc., to higher and safer places.
• Disconnect all electrical appliances.
• Turn off electricity and gas before you leave the house.
• Tie your valuable items or articles and keep them in a safe and high place or bury it  underground.
• Shift the livestock and cattle to safe places or high land. Keep some feed and fodder for them.
• Insure household articles, livestock and crop.
• Collect your survival kit or basic essentials before leaving your house.
• Think of safety first during a flood.
• Take care when walking through shallow waters.

Don’ts:-

• Do not allow children to play in, or near flood waters.
• Do not wander around in a flooded area.
• Do not drive into water of unknown depth and current.
• Do not eat food, which is affected by flood waters.
• Do not try to walk or drive through flood waters.
• Do not walk across bridges as they may collapse.
• Do not contact flood waters to avoid contamination.
• Do not walk through flowing water - currents can be deceptive, and shallow,fast moving water can knock you off your feet. 
• Do not swim through fast flowing water or you may get swept away or struck by an object in the water.