A lot of people haven’t experienced flooding. We merely see pictures and videos on the news. Some people might even think it could be fun, but this is far from reality. A simple definition of flood is when there is an unusual excess amount of water in a new place. In more technical terms, flooding can be described as when water has overflown into an area that is normally dry. Flooding can occur due to various reasons. One of them is when a river overflows its bed, as a result of heavy and prolonged rainfall. It can also occur due to mechanical damages to drain pipes, sewers, and dam failure. Other conditions that could cause flooding include cyclone, tsunami and so on. There are various types of flooding, some of the include flash flood, which could occur suddenly and can also develop after heavy rainfall. Other types of flooding include catastrophic flooding, river flooding, coastal flooding, urban flooding and so on. Flooding has the capacity to cause damage to valuable properties, domestic animals, and human lives in severe cases. It can disrupt electricity and also wipe away an entire city. It’s important to hire the service of water restoration companies to help in stopping the flood, and also restoring buildings to normalcy. This might take a long time, but they get the job done and help eliminate most of the risks associated with flooding.
What Is Flooding?
Flooding is a natural event that occurs when a piece of land that is typically dry, gets submerged by water. This is mostly as a result of massive and long periods of rainfall. It can also occur to the pipe leakages, dam failure and so on. Floods can occur suddenly, and might also take a long time to develop. Flood usually give warnings, to people around, as they can see the water accumulating. However, there are some types of the flood that occurs shortly after a rainfall, and sometimes without rainfall. An example of this is the flash flood. The flood might recede rapidly and may take a long time, sometimes weeks and months before it recedes. Flood has the ability to cause damages to properties, domestic animals, destroy infrastructure such as roads, bridges and even clear out an entire city. In severe cases, flooding can cause the loss of human lives. Some of the essential things to know about the flood are that it occurs in irregular intervals, and it differs in size, duration, and location. Other things to note include the following:
- Water naturally flows from high areas to low lying areas. This makes low-lying areas more prone to flood.
- Trees, shrubs help to reduce the flow rate of water, thereby helping in reducing flooding and erosion.
What Causes Flooding?
The most common cause of flooding is rainfall. However, there are other conditions that could lead to flooding. Below are some of the common ones:
- Rainfall: As earlier mentioned, heavy rain that falls for a long time is one of the most common causes of flooding, especially in places with poor or no drainage system. Places with drainage system can also be overpowered with an excess amount of rain. Heavy rain that falls for a short period of time can lead to flooding, and light rain that persists for a long time can also lead to a flood.
- River overflow: There are situations where rivers or other water bodies overflow their banks. This would cause water to flow to areas where it shouldn’t be. River overflow occurs when there is more water upstream than normal, and as it flows downstream to the adjacent low-lying areas. There might be a burst in the water flow, which would make the water get into the land.
- Hurricanes, strong winds in coastal areas: This is a condition in which strong and massive winds carry water from the sea onto dry lands and coastal areas. This usually worsens when the winds carry rain themselves. Tsunami is also an example. It has led to the destruction of properties worth billions of dollars, and thousands of lives. This has occurred in places like Japan, Florida and so on.
- Obstruction to the natural flow path of water: There are situations in which the natural path of a water channel is blocked by materials. This is common in places that people erect buildings illegally on the natural path of water. Flooding would be prevalent in this place until the structures that are blocking the flow of water is removed.
- Dam breaking: A dam is a man-made barrier that is made to restrict the flow of water. Reservoirs created by dams help to prevent floods, and also in the generation of electricity. In addition, they are also useful in activities such as irrigation, industrial use, human consumption, for agriculture and so on. However, there are cases when there is too much water in the dam, which could cause it to break and overflow the surrounding area. This usually occurs without warning. It could cause a type of flood known as a flash flood, which can be dangerous, as it removes everything it comes in contact with.
- Melting of snow and ice: Flooding mostly occurs in tropical regions during the raining season, but happens in other climes shortly after winter, when the snow or ice caps are melting. This would occur when there is a sudden increase in temperature, leading to a massive movement of water into places that are usually dry.
- Deforestation: Trees, plants and their sediments help to hold water. However, environments in which the trees have been removed are prone to flooding. This is why communities encourage the planting of trees. Apart from boosting the aesthetics of the community, and in wind breaking, they also help to prevent flooding.
- Poor drainage system: Drainage system are supposed to help prevent flooding, and also aid the flow of water during rainfall. However, there are some conditions that impair the function of drains. An example is the accumulation of litters in the drain, especially in open drains. These litters block the drain and prevent the flow of water during rainfall, which might eventually lead to the overflow of water, and hence flooding.
What Are The Types Of Flood?
There are various types of flood. Below are some of the major ones:
- Flash floods: This is one of the most dangerous types of flood. It could occur suddenly, and can also give some warning before happening. It mostly occurs shortly after heavy The time duration could be between 2 to 6 hours. Flash flood has the capacity of sweeping away whatever it comes across. Flash flood could happen suddenly, without any warning or notice. This could be due to the failure of dams, water pipe leakage, ice cap melt or snowmelt. Flash floods have the capacity to destroy properties, valuables, domestic animals within a short period of time.
- Rapid on-set floods: This type of flood is similar to flash flood in some ways. However, they take some more time to build up as opposed to flash flood. In addition, this type of flood usually doesn’t last more than a day or two. It’s very destructive but doesn’t occur suddenly like flash floods. This type of flood gives me enough time to evacuate and prepare for the impending flood, thereby leading to minimal destruction of properties and valuables.
- Slow on-set floods: As the name implies, this is the type of flood that takes a long time to occur. It occurs when a water body overfloods its bank. This might take weeks to months for it to accumulate. There have been situations where it spreads over a long distance. In addition, it mostly occurs in flood plains. This type of flood has a lot of health implications for people that live in the environment. Some of the risks associated with slow on-set flood include diseases, malnutrition, and snakebites.
- River flood: This is the type of flood that occurs when a river overflows its bank. This can happen due to prolonged and heavy rainfall. This type of flood mostly occurs when the natural water path is blocked. An illustration is when an illegal structure is built on the natural path of water. Something as little as a light rain can result in flooding in this type of condition. Other factors that could lead to river flooding is the sudden increase in temperature, especially in places where there are lots of snow. The sudden rise in temperature would melt the ice, and cause them to flow. River flow has the ability to damage properties and lives. However, they take time before they occur, so people can evacuate and prepare for the impending danger.
- Coastal flood: Coastal flood is the type of flood that occurs along the coast of a river, lakes, ocean and so on. They occur when there is a rise in the ocean tide, which might be caused by strong winds. Coastal areas are always the first to be hit and affected when there is a flood or storm. Examples include cyclones and tsunamis. Other conditions that could lead to coastal flooding include a rise in sea levels. Low-lying seaside areas usually have some sort of defense against a rise in sea level. This might be man-made and can also be natural barriers such as sand dunes. Coastal flooding is expected to be more predominant as time goes on, mainly because of global warming.
- Storm surge: This occurs when there is an unusual increase in the level of the water body. This might be as a result of high waves and strong winds, combined with low atmospheric pressure. This type of flood is dangerous, and can quickly put coastal areas under. Some illustrations of storm surge would be the various Hurricanes that has happened in recent years. An example is Hurricane Harvey, in which about 200 billion dollars worth of property was lost. Storm surge can also lead to the loss of domestic animals and human lives. A total of about 1600 people died in Hurricane Katrina. Storm surge bears the greatest risk to human lives and properties, especially those that live in coastal areas.
- Urban flooding: Urban areas usually have a problem with population and space. This is because people naturally, prefer to live in these places, because of the various opportunities to make money, and improve their lives, as compared to small towns and rural areas. However, this might also put some strain on the drainage system. Places that make use of open drains have a high risk of experiencing flooding. This is because people tend to throw their litters in drains, which would block accumulate and block the drain. This would prevent the flow of water, causing it to overflow, and flood properties, buildings and so on. Other conditions that could lead to urban flooding include the leakage of water pipes. This can lead to flooding if not controlled promptly.
- Catastrophic flooding: This is the type of flooding that occurs due to the damage to infrastructure. This could be as a result of natural occurrences such as earthquakes. Other conditions that could lead to catastrophic flooding include the failure of dams. This type of flooding can cause the destruction of lives and properties within a short time.
There are various and many more types of flood. However, above are some of the common ones. It’s important to know that all types of flood are capable of causing damages of properties and loss of lives. Below are some of the ways of preventing flooding.
How To Prevent Flooding?
There are some things that can be put in place to prevent some type of floods from happening. As mentioned earlier, most types of the flood are caused by rainfalls, and when rivers overflow their banks. Below are some of the ways of preventing floods from happening:
- Coastal defense walls: Places that are prone to strong tidal waves can benefit from sea walls. This wall is built like a gate to prevent the waves from pushing waters up ashore. There are other alternatives to sea walls such as sandbags. These bags are placed in strategic areas, as they help to absorb and retain floodwaters.
- Vegetation: It was mentioned earlier that deforestation is one of the causes of flooding. On the other hand, forestation is one of the ways of preventing flooding. Vegetations such as shrubs, trees help to break the flow power of water, especially when heavy rain falls. People that have buildings and properties in low-lying areas can benefit greatly from planting vegetations on their land.
- Town planning: One of the most effective ways of preventing flooding is by ensuring people follow the original plan of the city or town. Builders have to build houses according to the plan of the town. There are situations where people erect buildings on waterways. This would lead to flooding, even after a light In addition, drainage systems have to be covered. People tend to throw litters in uncovered drains, which would obstruct the flow of water, and cause the overflow of the drains, hence flooding.
- Education: This is also connected to the drainage People should be educated about the implications of throwing litter in drains. This would not only cause flooding when it rains but would also cause the stagnancy of water. Stagnant bodies of water support the breeding and growth of mosquitoes. In addition, dangerous microorganisms also grow in this environment, which might lead to the spread of diseases. Overall, it’s important to educate the people about the dangers of throwing litter in drains.
- Detention basin: Detention basins are small reservoirs that are built and linked with waterways. They serve as temporary storage for flood waters. This ensures that in any case of flooding, water would initially drain into the basin. This usually gives people sufficient time to evacuate and keep their valuables away. This also helps to reduce the magnitude of downstream flooding.
Which Areas Are More Prone To Flood?
There are various types of flooding, and each type of flooding has its own cause. However, there are some areas that are more prone to flooding. Some of them include the following:
- The topography of land: It has been shown that low-lying areas are more prone to flooding. This can be attributed to the natural behavior of water. Water tends to flow from higher ground to lower
- Places that experiences lots of rainfall: Typically, places that experience lots of rainfall are more prone to flooding. This is because the ground gets saturated after some few hours of absorbing water, the remaining water would then flow to surrounding areas. Flooding rarely occurs without rainfall, except in situations where it’s caused by mechanical damages such as pipe leaks, dam failure, obstruction of drains and so on.
- Illegal construction of buildings: There are places where people erect illegal structures on natural ways of water. This would lead to flood whenever it rains. One of the ways of preventing this is by ensuring people follow the original plan of the town.
What To Do Before, During And After Floods?
It’s important to have some knowledge of what to do in case a flood happens. Asides from a flash flood, all other types of flood usually give some warning before
they happen. Flash floods also give some warning, except in situations where they occur due to mechanical damages such as dam failure, pipe leakages and so on.
Before The Flood
Flood usually takes time to build up. They might take from an hour to six hours to build up before they start flowing with high power. Below are some of the things you should do before the flood:
- Ensure you know the various evacuation routes out of your building, and also understand the local relief centers.
- It’s important to familiarize yourself with the various emergency numbers. You can store them on your phone, or write them on a wall everyone can see clearly.
- Keep a stash of emergency supplies such as flashlights, water, canned food, and first aid items.
- Ensure you store your valuables safely. You can put them in a well-sealed plastic container.
- You should plant vegetations such as trees, shrubs in your compound, especially if you live on the low-lying As earlier explained, water moves naturally from high ground to a low-lying ground.
During The Flood
- Flash flood usually starts suddenly. It’s important to keep kids and elderly ones safe. This can be done by placing them on higher
- Switch off all electrical appliances, gas, heating and so on. This is to prevent any case of electrocution or other types of accident.
- Endeavour to avoid getting in contact with flood water. This is because the water might be contaminated with toxic and hazardous materials.
After The Flood
- It’s important to contact to ask emergency officers for permission before moving into your home.
- Ensure everywhere is dry before moving into your home.
- Take pictures of your home, as this can be used as proof which could be needed for insurance claims.
- Protect yourself when cleaning. You can make use of masks and gloves.
How To Protect Your Health During Flooding?
Flood causes a lot of damages. This includes the destruction of properties, loss of domestic animals, infections, release of dangerous chemicals into the flood water, presence of dangerous animals in the water, such as crocodiles, snakes and so on. Below are some of the things to be careful of:
- Drowning: It’s important to stay away from water if you know you can’t swim. You never can be too sure how deep the water is. You should endeavor to wait for help, then risking your life.
- Avoid floodwater as much as you can: Flood water contains various types of substances, which could include chemicals from industries, sharp objects, snakes and so on. Try to say on higher ground as long as you can, till help comes.
- Skin infections: Flood water usually contains the feces of animals and humans. You can’t be too sure what type of microbe is present in these materials.
- Mosquito infections: Flood water is the ideal place for mosquitos to breed and grow. This is because flood water is mostly stagnant. People can be exposed to mosquito infections. In tropical regions, they can cause diseases such as malaria, which can lead to death if not well managed.
- Gastrointestinal infections: Flood water is usually contaminated, and this is because of the various microbes, materials present in flood water. It’s impossible to swim in flood water, without getting ingesting some of the flood water. Victims of flooding should endeavor to visit the hospital as soon as they have the opportunity.
- Mould: Molds grow in humid environments, which makes a flooded environment an ideal habitat for them. It takes a long time for a flooded house to dry up, especially when it’s left unmanaged. Molds tend to grow in these places, which would put the occupants in a lot of risks when they eventually move in. However, it’s important to know that not all types of molds are poisonous
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