What is flooding?

If you have a potted plant at home, I am sure you take time to water it.

Suppose, one day, you put so much water that it overflows from the brim of the flowerpot.

Now, the water will harm the plant instead of helping it grow.

Our Earth is a giant ecosystem that is sustained by periodic rains. These rains replenish our water resources and provide water for our crops (agriculture).

These crops provide food to all humans.

As you already know, this cycle is called the water cycle.

But sometimes, the earth is not able to absorb all the rain that falls, just like our flowerpot.

At such times, first, just like with the flowerpot, the water fills to the brim. This leads to flooding in the area.

Then, like with our flowerpot, the water overflows into the neighbouring areas.

What happens in a flood?

Water enters fields, roads, houses, factories, etc.

The water level determines how severe the flood is. For example, in this image, the flood is just about starting. The water has not entered the houses yet.

But in this one, many houses are submerged.

Why is a flood bad?

First, of course, is the damage to property itself. When books get wet, they get spoilt. Same for furniture at home, machinery in factories, and crops in fields. They are physically destroyed by the flood waters.

The second problem is that flood waters can lead to people and animals being electrocuted. So, as soon as flooding occurs, typically, power is disconnected to the area. This means that even people whose houses are not flooded, have to make do without power and clean water (water pipelines are also polluted by this dirty flood water).

The third issue is that flood waters also carry debris and trash. All the dustbins that fall in the path of the flood. This trash is left on the sides of the roads as the water recedes.

The fourth issue is that flood waters lead to spread of infection and disease. Since water from drinking water sources is polluted, water borne diseases can spread much faster.

How is flood relief done?

As the first step, people are brought to a safe place and provided safe water and food.

The second step is to minimise the damage because of floods. Water pumps are used to pump out water wherever possible.

The third and the most difficult step is to rehabilitate the people whose houses were damaged by the floods.

Sometimes, it is not possible to evacuate people. At those times, we have to ensure that they get food, clean water, and basic medicines in their houses. That is called relief material. It is usually air dropped – i.e., given to people using helicopters.