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DISASTER MANAGEMENT OVERVIEW: FLOOD RISK

DISASTER MANAGEMENT OVERVIEW: FLOOD RISK

We have observed incident trends of late amongst localities and even countries; it has become a very disturbing issue the spate of flood risk exposure amongst vulnerable settlements and communities. This disturbing flood disaster has again been identified as one of the fall outs of global climate change which we have all been collectively responsible for. This trend would continue and even go worse if we do not see the care of environment as our individual and collective responsibility, the need to change our attitude towards the mother earth is of utmost concern if we really desire to put a check or control to these natural disasters that we are left to contend with.

Many communities in Nigeria suffered colossal loss 2012 owing to the unexpected flood disaster that ravaged some parts of Nigeria. This could have been avoided or mitigated if we clearly identified and recognise the peculiarity of risk we are exposed to base on our geographical positioning. It does not really matter how you pay deaf ears to the sound and presence of those risks, one thing that is clear is that they will surely occur whether you plan for them or not. Planning will help mitigate the effects and facilitate quick and better recovery.

The best and most important approaches to disaster management are Planning and Right Attitude. These two factors are key components in effective disaster management. Planning talks about the conscious preparedness you have put in place to mitigate disaster should they occur, this spans from strong framework policies driven by government, people engagement and participation, funding, partnerships, education and training, Health, provision of relief camp and materials etc. These and many more constitute part of the planning processes and must be sequentially designed, tested, evaluated and reviewed routinely.

Flood as it concerns us in the context of this presentation has been defined as an overflowing of a large amount of water beyond its normal confines or boundaries, especially over what is normally dry land.

Flooding is said to occur when land not normally covered by water becomes covered by water or when heavy rainfall overwhelms the drainage capacity of the local area.

Flood disaster always has a huge impact on:

  • People
  • Property
  • Economy
  • Overall environment

Flood risk is mostly caused by the effect of climate change such as severe rainfall and rising sea levels which normally increases the risk of already affected areas and put other areas that may not have been flooded in the past at risk also. We need to me more vigilant than we were in the past as a way of adapting to the reality of climate change in ensuring the risk of future flooding is integrated into the planning through spatial planning processes at State, Regional and Local levels.

Flooding seem to be catching up with most emerging metropolis and mega cities like Lagos, Mexico, New York and the likes. This is due to the massive economic development projects to meet the socio-economic need being embarked upon without due hydrological and environmental consideration, this most times leads to destructive incidences even in regions that used to be considered safe.

LAGOS OVERVIEW

Lagos is a coastal city bound to experience coastal flooding caused by higher sea levels than normal, largely as a result of storm surges, resulting from the sea overflowing into the land. There is also the issue of inland flooding which is caused by intense or prolonged rainfall which Lagos has of late been characterised with.

Coastal flood is greatly influenced by 3 factors namely:

  • High tide level
  • Storm surges caused by high winds
  • Wave action which is dependent on wind speed and direction, local topography and exposure

Flooding may also arise from failure of infrastructures designed to store or carry water or to protect an area against flooding e.g. the breach of a dam, leaking canal or a burst water main, breach of a flood defence, failure of a flap valve or pumping station or blockage of a pipe or culvert. The impact of such sudden flood unset can be severe and must be assessed in planning.

Interestingly, Lagos, apart from being the industrial and commercial hub of Nigeria and the West African sub-regions, it is also the biggest city in West Africa, and it is projected to be one of the world’s five largest cities by 2015 (Federal Ministry of Education and Research, 2004). It has a very diverse and fast-growing population, thus normal pressures of urbanization and forces of modern development has resulted in the city expanding to nearby suburbs like Lagos NE, which politically covers Lagos and Ogun states of Nigeria.

Unfortunately, the encroachment and development of the suburb best quality farmland, large scale massive deforestation and loss of surface vegetation are being carried out in an unplanned mode. Even the  encroachment of urban facilities on Ogun River and its tributary floodplain (waterways) and unprecedented land reclamation without strict adherence to land use and natural waterways planning, is also evident. With all these indiscriminate occurrences, we wonder if the Land Use Act is still an effective Act to implement or does it need an upscale in form of review or some people are not just able to enforce the content of the document. If we allow this spate to continue, the disaster that we are currently faced with will be nothing compared to what is to come. Urgent behavioural change has to be pursued and achieved to enable us have a sustainable environment, not void of risk but environment where risks are under considerable control. Flood is therefore being aggravated through numerous physical and social alteration of the natural environment, which has increased the impervious surfaces (Oyebande, 1990), and occupancy of unsafe land and hazard prone region, without an appreciable harmonizing scheme between nature and the developmental activities. This has created a lot of social and economic cost on the environment and the citizenry. The need to resolve the severe flood incidence within parts of Lagos NE, call for proper estimation and mapping of floodable areas at acceptable risk level, in order to provide essential tools needed towards attaining an integrated flood pre-disaster and lead-time scheme within the region.

Having this background in mind, we need to assess the levels of plans and preparedness measures we have put in place to ensure the potential impact of flood at the really of hazard is rightly minimised. The approach to this is to identify the vulnerable groups, their different levels of exposure and what we all stand to lose. Flooding has been known to induce the following:

  • Physical injuries, illness and loss of lives
  • Deep, fast flowing or rapidly rising flood waters can be particularly dangerous. Even shallow water flowing at 12 metres per second (m/sec) can knock children and many adults off their feet.
  • Some of these impacts may be immediate such as drowning or physical injury due to being swept away by flood.
  • Flood water contaminated by sewage or other pollutants such as chemicals is particularly going to cause illness either directly as a result of contact with the polluted flood water or indirectly as a result of sediments left behind.
  • The mud ways also causes physical hazards via slips and falls.
  • Some of such health diseases include nasal congestion, respiratory infection, diarrhea, flu etc.

Flood also has impactful damage on properties in diverse ways as highlighted below:

  • Flood water is likely to damage internal finishes, contents and electrical fittings, and other services and possibly cause structural damage.
  • Re-occupation of a property damaged by flood could take a long term and huge investment has to be made for cleaning and restructuring.
  • Vehicles and equipment are not spared also in this impact.
  • Sea water may cause additional damage as corrosion.

Public infrastructures are not left out in the potential damage and they come in the forms below:

  • Flooding impact on infrastructures such as transport and utilities as electrical and water supply can have significant detrimental impact on local and regional economies.
  • Flooding of primary roads can deny access beyond those areas directly affected for the duration of the flood event, as well as causing damage to the affected roads, people cannot go to work, children cannot go to school etc.
  • Flooding of water distribution infrastructures such as pumping station or electricity substation can result in loss of water or power supply for large areas.
  • This can magnify the impact of flooding well beyond the immediate community.
  • The long closure of businesses can lead to job losses and other economic impacts.

Having taken our time to carefully look at the effect of flood disaster and how it impacts on human beings and our entire environment, i would rather think it should be given a very significant place in day to day running of government if indeed the government owns the responsibility to secure lives and properties of the citizenry. Budget and requisite funding should be made available and rightfully deployed and appropriated in the interest of the people and the environment at large. There is the need to have a legal document on National, State, Regional and local disaster management which must be made available or made accessible to everyone so we all know what our roles are when it comes to disaster management. Most times, what we see or hear is mere political boastful statement that amounts to nothing at the end of the day.

It might interest you to know that the geographical land mass affected by the disaster that struck Haiti was far less than the geographical land mass affected by the disaster that struck Chile and even Japan. But Haiti suffered more loss compared to Chile and Japan, this is a clear indication of the economics of disaster preparedness plan with high commitment of time and resources.

Like we all may have known, disaster management comes in 4 circles namely:

Preparedness: Readiness activities effected to minimise loss or damage

Response: What we do when disaster strikes

Recovery: When we start to ask questions on what we have learnt and what we can do to make the next if any, better.

Mitigation: All the things we can do to make us survive disaster

These all involve a thorough risk assessment which must cover plans as:

Communication: This has to do with information ins and outs. In time of disaster people need to know what to do, the safe places to evacuate to if they have to, the roads that are open and safe to drive through, where to get treatment or food during such situation. The designated authorities most times have what is referred to as incident command system that has a number of structures which also covers communication. You all need to have a family or personal preparedness plan and a jump bag which must include a small battery powered transistor radio to get information and instructions on development outside your immediate environment.

Security: In most disaster situation the most important concern is not to add to the burden of work already getting everyone overwhelmed, whether you are a responder or not you also need to get back home safely at the end of the day hence the need for security plan as an important consideration.

Authority: In situation as disaster, the need to have someone who has been appointed to take charge is important else everyone does what he or she likes and complicates issues for everyone. We need to plan for an incident command system and appoint someone who have been trained and experienced to take charge; he is the leader of the entire disaster management structure.

Disaster management comes with basic need as:

  • Water
  • Food
  • Shelter
  • First Aid
  • Environmental concerns
  • Tools
  • Comfort and more

We also need to know in time of disaster, we also need to help when we are in a better state to do that. We also need to know what the “old normal life” and the “new normal life” means and our ability to adapt to the new normal life psychologically will help us a great deal. You may have owned and lived in a very comfortable apartment with Jacuzzi but you may have to sleep on a debris hut with minimal cold shield during disaster. You need to condition your mind to be able to survive this difficult period and you also need to make personal survival plan for basic needs that will last you for a minimum of 3 to 7 days. Meals Ready to Eat (MRE) are mostly what you will have to depend upon (mostly dry and canned food), you may have food to cook and there is no water, no gas or stove or even cooking pot. But with dry or canned foods, they do not perish easily and they are as good as food on-the-go.

Have you ever asked what could be done when you run out of potable water? In disaster situation, you may need to create potable water by treating water with drops of chlorine bleach, iodine tablets, steri pen and other filtration system. Boiling is an option but it is a luxury in a disaster situation, you can also use other means of water filtration systems. All these mentioned above is to kill the germs (bacteria and virus) so you do not get sick of enteritis but this cannot take care of the particulates but the filtration system does. You need an average of 1 gallon of water per person per day, so you need about 7 gallons of water to survive for 7 days. This is important so you do not suffer dehydration that could make you vulnerable to illness.

To be continued………………………………

Some of this information shared is from the work of Olusegun Adeaga of Department of Geography University of Lagos, other personal research and teaching from Dr. Michael Beach who is my course instructor in my on-going course on Disaster Management at University of Pittsburgh, Pennsylvania USA. I should be done in 3 weeks when i will have the time to share a number of new things with you.

Thanks for always following my blog and the very good comments left behind are really encouraging. Keep them coming.

Ehi Iden

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Ehi Iden editor