Flooding in Central Georgetown (Photo Bryan Maxx)
Of all natural hazards capable of producing a disaster, a flood is the most common in causing loss of life, human suffering inconvenience, widespread damage to buildings, structures, crops, infrastructures, and other national assets.
Severe weather conditions which lead to intense rainfall such as tropical depressions and hurricanes often lead to flooding.
What are the Different Types of Floods?
There are four types of flooding that affect Guyana and the wider Caribbean are:
1. Flash Floods:
Flash floods are the result of heavy rainfall or cloudburst over a relatively small drainage area. Flash floods carry highly destructive flood waves and are most common in mountainous areas or in steep places that have streams flowing through narrow canyons.
2. Riverine Floods:
This usually occurs when a river overflows its banks. It is usually due to the volume of water within a body of water, such as a river or lake, exceeding its capacity and overflowing its banks. It can also occur in rivers where the velocity of the water is so high it flows out of the river channel, usually at the bends.
3. Tidal Flood:
This results when large bodies of water, like seas or lakes, overflow onto bordering lands. They are mainly caused by high tides, heavy rains, waves resulting from high wind surges created by storms, and long waves produced by earthquakes out at sea.
4. Ponding:
This is a slow build up of water in depressions, sinks, clay base soil and slow percolation rate areas, for example, the Lower East Coast.
What Causes Floods? The main causes of flooding in Guyana are as follows:
- Heavy rainfall resulting from tropical weather disturbances
- Deforestation
- Improper garbage disposal techniques
- Improper agricultural practices
- Inadequate design of drainage channels and structures
- Inadequate maintenance of drainage facilities, blockage by debris brought by flood waters
- Construction of settlements in flood plains
Flooding is also a natural feature of drainage systems and of rivers and streams. It occurs when drainage channels are filled disallowing rivers and streams from accommodating the excessive water generated by severe weather conditions. The drainage channels then brink their natural or artificial banks and water enters the surrounding lands to cause flooding.
Also human activities, which damage the environment, for example, sand mining and deforestation increase the risk of flooding.
Areas most likely to be worst affected by flooding are:
- Low-lying coastal areas
- Areas near river banks
- Flood plains of major rivers
- Areas vulnerable to landslides
- Low-lying coastal towns and villages
What are the Effects of Floods?
Floods can:
- Disrupt one’s personal, economic and social activities.
- Set back the nation’s security and development by damaging or destroying roads, buildings and other infrastructure.
- Cause death by drowning.
- Lead to insufficient food supply, which can lead to famine.
- Destroy crops and livestock.
General Flood Precautions
- Remain calm and take all necessary precautions.
- Make sure you have a battery-operated radio with extra batteries. Follow all instructions. If told to evacuate, move out of the house or building to a safe, high ground.
- Turn off all utilities at main switch if evacuation is necessary. Do not touch any electrical equipment unless it is in a dry area or you are standing on piece of dry wood with rubber footwear and gloves.
- Remove all valuables. Wrap all important personal items, family documents electrical appliances, pictures and wall hangings in plastic bags.
- Avoid already flooded areas. Do not attempt to cross any stretch of floodwaters on foot if water is above your knees.
- Cars can become coffins in floods. DO NOT drive where water covers the road, since under these floodwaters the road could already be washed away. Also rapidly rising water could lift the car and carry it away.
- Do not go sightseeing in flooded areas.
- If caught in a house by suddenly rising water move to second floor and/or if necessary, to the roof. Take warm clothing and a flashlight with you – as well as a battery operated radio. Wait for help.
- Use only recommended routes if you must travel.
After the Flood
- Listen to the radio for instructions.
- When returning home and before you enter the house, be sure that the structure is not in danger of collapsing:
- Move about the building slowly
- Donot touch electrical appliances or fixtures
- Open windows and doors to let air circulate. This will help remove foul odours and protect you from escaping gas. It will also help to dry out the house
- Take pictures of damage both to the house and its contents for insurance purposes.
- Get in touch with your insurance company – if your house was insured.
- Begin clean up as soon as possible. Throw out any perishable foods since they may be contaminated.
- You may need to hose down furniture if mud is lodged on them.
- Shovel out mud while it is still moist. Dry rugs and carpets thoroughly.
- Make necessary repairs to stop further losses from the elements or from looting.
- Boil and store drinking water.
- Keep garbage tightly sealed.
- Cover and protect food.
- Prevent mosquito breeding by punching holes in all containers in which water can settle.
- Keep garbage tightly sealed.
- Do not walk barefooted outside, during or after a flood. Wear water resistant boots or shoes.
- Do not go sightseeing in flooded areas.
- Do not touch loose or dangling electrical wires.
- Exercise caution when crossing bridges and passes that are near to rivers and streams. Use only recommended routes.
- Bury all dead animals as soon as possible.
- Do not go swimming in floodwaters.
- Follow evacuation orders carefully.
Evacuation
Flooding often cause forced evacuation. The process of evacuation is normally affected to remove a threatened community from a high risk factor.
The evacuee is often being asked to leave the security of his/her home to an impersonal setting. This is often in the form of shelters – located at some schools and churches.
The decision to evacuate is often a difficult one and at times may be resisted by residents, as they often have to leave behind their possessions unprotected. Moving to a shelter should be a last resort rather than a first priority. Thus, care and understanding should often be exercised when dealing with persons who are reluctant to move.
There are specific factors to be considered for an evacuation process:
- Critical facilities: determine if these are located in vulnerable areas.
- Population: size and characteristics of population to be moved, health status, vehicles and medical arrangements required.
- 3Communication: during evacuation, communication is extremely important. This is often necessary to ensure that all evacuation activities are proceeding as planned. Since efficient communication is key Citizen Band (CB) Radios are often utilized.
- Route determination: the route should be selected based on the capacity to ensure free access and in cases where evacuation is over a long distance; all primary and alternate routes should be mapped.
- Personal documents and records: family members evacuating the area should secure all personal documents and records.
- Since the duration of the stay away from home is unpredictable, gas, electricity and water should be turned off.