DISASTER MANAGEMENT IN NIGERIA: FLOOD CONTROL

THE PRESENTATION EXAMINES Introduction Basic Concepts on Disasters Management Flood: types and causes Flood Control Flood safety tips

INTRODUCTION Disaster is as old as man and man had

always had to look for ways of combating it so that he is not overwhelmed and destroyed. In the bid to combat this menace, man had developed strategies which were not really effective.

The need to avert or fight disasters whenever it occurs led to the evolution of disaster management.

BASIC CONCEPTS Disaster is a serious disruption of the

functioning of a community or a society causing widespread human, material, economic or environmental losses which exceed the ability of the affected community or society to cope using its own resources (ISDR, 2004).

It can also be referred to as a sudden calamitous event bringing great damage, loss or destruction

Disaster ManagementAll the measures/activities that are aimed at impeding the occurrences of a disastrous event and for preventing/reducing the negative impact of such occurrence on communities. It is made up of

Preparedness Mitigation Response Relief Recovery

Emergency This is any event or circumstance

( happening with or without warning) that causes or threaten death or injury, disrupting to the community or damage of property or to the environment on such a scale that the effects cannot be dealt with by local emergency services, local authority and other organisations as part of their normal day activities.

DISASTER RISK REDUCTION Disaster Risk Reduction is a PRO-active

approach to Disaster Management and includes measures aimed at reducing the direct and indirect impacts of a disaster. A process concerned with reducing the disruptive effects of hazards by building community capacities and resilience.

‘’The conceptual framework of elements considered with the possibilities to minimize vulnerabilities and disaster risks throughout a society, to avoid (prevention) or to limit (mitigation and preparedness) the adverse impacts of hazards, within the broad context of sustainable development.“ UNISDR

] DRR is focused on reducing vulnerability

and building resilience of community members

FLOOD DISASTER Water covering previously dry area: a

very large amount of water that has overflowed from a source (such as run-off resulting from heavy rainfall, melting snow, rivers overflowing their banks, collapsed dam or from a broken pipe) to a previously dry area.

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“Floods are among the most devastating natural disasters in the world, claiming more lives and causing more property damage than any other natural phenomena”

(Bolanle Wahab, August 2012)

TYPES OF FLOODFloods can be classified into 3 broad categories

i. Meteorological: As a result of rainfall of a long duration – resulting from saturation of the soil

ii. Coastal floods: when storms and heavy waves bring seawater on to the coastal land

iii. Flash flood: lots of rainfall over a short period of time. Occurs with little or no warning and cause the highest loss of human life, damage to infrastructure and public and private property

CAUSES OF FLOOD Floods are caused by many factors: heavy

precipitation, severe winds over water, unusual high tides, tsunamis, or failure of dams, levees, retention ponds, or other structures that contained the water.

- Climate change – excessive rainfall- Release of water from local dams- Poor drainage network- Inadequate canals/culverts in view of present

climatic reality- Encroachment on river channels- Dumping of refuse in river channels

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EFFECTS OF FLOODS

Flooding has many impacts. It damages property and endangers the lives of humans and other species. Rapid water runoff causes soil erosion and concomitant sediment deposition elsewhere (such as further downstream or down a coast).

Effects of Flood The spawning grounds for fish and other

wildlife habitats can become polluted or completely destroyed.

Effects of Flood Floods can interfere with drainage and

economic use of lands, such as interfering with farming.

Effect of Flood Some prolonged high floods can delay

traffic in areas which lack elevated roadways.

Effects Cont…. Structural damage can occur in bridge

abutments, bank lines, sewer lines, and other structures within floodways. Waterway navigation and hydroelectric power are often impaired. Financial losses due to floods are typically millions of Naira each year.

Collapsed Dam

Bridge cut off

Electricity and Communication cut off

Infrastructural Damage

LONG-TERM EFFECTS

Economic hardship due to a temporary decline in tourism, rebuilding costs, or food shortages leading to price increases is a common after-effect of severe flooding. The impact on those affected may cause psychological damage to those affected, in particular where deaths, serious injuries and loss of property occur.

FLOOD CONTROL Flood control encompass all the activities

involved in the prevention and mitigation of flood disasters.

These include: Non structural approach Structural approach

Non Structural Approach These are the intangible activities

embarked upon to prevent and mitigate flooding in our communities. They include but not limited to the following;

Education, Sensitization, Proper waste disposal, Proper Environmental Sanitation, Early warning signs etc

Structural ApproachThese are physical structures put in place by government as well as community members to prevent and mitigate flood disasters.

Flood controls, such as dams, can be built and maintained over time to try and reduce the occurrence and severity of floodsOther structures include;

Levee is an embankment constructed by the states along a body of water to prevent the flooding of lands adjacent to the water.

Bund wall, is a constructed retaining wall designed to prevent inundation or breaches from a known source.

Cont… Dikes, embankment, floodbank or stopbank

is an elongated naturally occurring ridge or artificially constructed fill or wall, which regulates water levels. It is usually earthen and often parallel to the course of a river in its floodplain or along low-lying coastlines.

Sandbags: A sandbag (floodbag) is a sack made of burlap, polypropylene or other materials that is filled with sand or soil and used for flood control. Sandbags may be used during emergencies when rivers threaten to overflow, or a levee or dike is damaged.

Culvert: is a structure that allows water to flow under a road, or similar obstruction. Typically embedded so as to be surrounded by soil, a culvert may be made from a pipe, reinforced concrete or other material.

Desilting of blocked drains, canals etcConstruction of proper drainage

network/systems

Clearing of rivers and streams in order to allow a smooth flow of water: Rocks, branches/twigs and other organic and inorganic debris can block the flow of water and facilitate inundation and damage to areas adjacent to such rivers and streams. This is especially important to combat flash floods.

Flood Safety TipsWe cannot stop the rains from falling but we

can stay safe during the rains. Avoid building in a flood plain. Always put barriers into consideration

when building to stop water from entering your house.

If a flood is likely in your area, listen to the radio or television for updates/information.

Cont… Know the difference between a flood

watch and a flood warning. A watch means flooding is possible. A warning means flooding will soon occur.

When a flood is imminent, pack a bag with necessary items in case you need to move. Don’t forget to include needed medications.

Cont… If advised to evacuate your home, do so

immediately. If you have an upper floor in your house, move essential items to the floor.

It is important to turn off utilities at the main switches if instructed to do so and disconnect electrical appliances.

During a flood, moving water can make you fall, do not walk through it but if you have to, walk where the water is still.

Cont… It’s dangerous to drive through flooded

area. If flood water rise around your car, move to higher ground if you can.

Do not touch electrical equipment if you are wet or standing in water.

After a flood, water around your area might be contaminated. Listen to news to learn whether the community water is safe to drink.

Cont… Avoid flood water as it may be

contaminated by oil, gasoline or raw sewage.

Water may also be electrically charged from underground or downed power lines.

In areas where flood water has receded, roads may have been weakened. Avoid such places.

Cont… You can return to your home only when

authorities indicate it is safe. Any building surrounded by water may be weak and may collapse, stay away.

Damaged sewage systems are serious health hazards, service them. Also clean and disinfect everything that got wet.

Mud left from floodwater can contain sewage and chemicals.

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In Case Of Emergency Call Toll Free

0800CALLNEMA080022556362

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THANK YOU