Flooding could be defined as the covering or submerging of land by water. Urban flooding is any flood in urban areas. Are there examples of flooding? What are the causes of urban flooding? How can we control Flooding? Read this article
Flooding; Definition, Causes and Examples
Definition of flooding
Flooding could simply be define as a body of water covering a mass of land where it initially wasn't present. From this definition, we could say that a flood is mostly unwanted. These floods (Especially urban floods) cause displacement of many and sometimes take lives.
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| Sango-otta Ogun state, Nigeria |
As you can see in the above photo, a street in Ogun state Nigeria is covered by water. The water level is so high that it almost covered a car. Floods like these can easily be avoided yet there still occur.
Causes of flooding
Rain
Rain causes flooding by increasing the water size and exceeding the capacity of the drainage system. When water becomes too much for the drainage system to carry at a time, flood occurs. Rain water can exceed drainage capacity either by being too heavy at a time or falling non-stop for days.
Wind
Strong winds and hurricanes carry sea water into land causing flooding. Wind just like earthquakes and other disasters, can displace objects and properties into blocking the drainage systems or other waterways.
Land Pollution
If the movement of water is stopped because of dirt disposed the wrong way, flood would occur
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| Flood in Lagos, though caused by high tide, stayed for a long time because of blocked drainage |
Dam breakage
Dams are man-made structures which hold flowing water and allow the water to flow through propellers to generate electricity. Sometimes, dams break due to age, cracks unattended to and pressure from the water. If a dam should break, all the waters it had being holding would flow at once, destroying properties, taking lives and causing floods.
Examples of Floods
View some pictorial evidences that floods occur everywhere in the world and we should do whatever it takes to prevent floods
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| Houston, Texas |
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| Northern New South Wales |
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| Rare wildlife killed as floods devastate India reserve |
Ways to Prevent flooding
Clear drainage systems
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| Drainage system filled with dirt |
In order to prevent flooding caused by land pollution, we need to clear these drainage systems so they'd be free from dirt.
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| Volunteers at the Ikotun Market, Lagos clearing the drainage system |
Build more drainage systems
There are some streets with no drainage system at all. Even the smallest rain fall would cause water to accumulate. To solve this problem, drainage systems should be built
Channel water to another location
You could build more drainage systems to drive the water into rivers or the sea. If there isn't any around, you could drive the water into burrow pits
Don't block water ways with irrelevant structures
Rain water flow to lower plains. If the means to reach the lower plane has being blocked by buildings, the water would no longer flow and cause flooding. Not building on water ways is among the ways to prevent flooding on urban areas.
Make good use of Burrow pits
This is a cheap and reliable way to prevent flooding especially in developing countries. A burrow pit is an engineering term used to describe a place where materials (like sand) have being dug from to complete a construction. Burrow pits are usually deep. Burrow pits can be useful to prevent flooding because water can easily flow on them and hardly flow out since they're deep. Sign posts to alert people of a very deep body of water should be put in place though
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| Burrow pit in Port Harcourt, Nigeria |
The burrow pit in the photo above is large and is used to keep rain water to prevent flooding. Without this burrow pit and others around, the city of Port Harcourt Nigeria would've been covered in water.
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| One of the entrances to the burrow pit |
The entrance in the photo, as you can see, will soon be blocked because of dirt disposed the wrong way. When it eventually becomes blocked, the streets around would be flooded.
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| Garbage found above the burrow pit |
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| The street is becoming covered with the dirt |
The two photos above are the same dirt between a street and a burrow pit. The people of this street Igbogo in Port Harcourt Nigeria are faced with the dilemma of either leaving the dirt on the road (so that the burrow pit can still help prevent flood) or pushing the dirt in to the burrow pit (so that the road will be clean once again).
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| Since this place have being left as a garbage site, it is becoming an eyesore to people and a threat to the environment |
Case study: 2012 flood in Nigeria
Cause: Rain and Reservoir
Location: 33 out of 36 states in Nigeria
Duration: July to October 2012
Death toll: 363
People displaced: 2,100,000
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| Lokoja, Kogi state |
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| Abuja |
This article was created to share awareness to everyone about the causes and control of flooding. Please read
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