Almost daily we hear news that another massive disaster has affected human life and property somewhere. There are several types of hazards that captivate the attention of general public and many of whom who are directly affected by such event. One category of natural hazards are flash floods which are said to be the most lethal form of natural hazard that causes a lot of destruction.
But before going deeper into details about flash floods, we must first understand what flash floods are and how do they occur.
Flash flood, according to World Meteorological Organization, is a rapid and extreme flow of high water into a normally dry area, or a rapid water level rise in a stream or creek above a predetermined flood level beginning within six hours of causative events such as excessive rainfall, a dam or levee failure, or a sudden release of water held by an ice jam which causes the river or stream to overflow and flood the surrounding area. Most flash flooding is also caused by slow-moving thunderstorms, thunderstorms repeatedly moving over the same area, or heavy rains form hurricanes and tropical storms.
There are two key elements that contribute to flash flooding, the intensity which is the rate of the rainfall and duration is how long the rain lasts. Flash floods often impact poorer populations in remote locations. It can be dangerous and destructive in almost any part of the world. Flash floods can roll boulders, tear out trees, destroy buildings and bridges. Furthermore, flash-flood producing rains can also trigger catastrophic mud slides .
One of the keys to understanding flood risk is understanding the type of flash floods. There are three common types of flash flood and each one bears a different impact in terms of how it occurs and the damage it causes.
Secondly, Fluvial flood or riverine flooding, occurs when excessive rainfall over an extended period of time causes a river to exceed its capacity. The damage from a river flood can be widespread as the overflow affects smaller rivers downstream, often causing dams to break.First, is the Coastal flood, as the names suggests, occurs in areas that lie in the coast of sea, ocean or other large body of open water. It is typically the result of extreme tidal conditions. In this type of flood, water overwhelms low-lying land and often causes devastating loss of life and property.
Thirdly, Pluvial or Surface flooding, is caused when heavy rainfall creates a flood event independent of an overflowing water body. It can happen in urban area even in higher elevations areas that lie above coastal and river floodplains.
Flash floods are dangerous and can cause death. . So here are some safety tips to help you assess the occurrence of flash flood.
If you must prepare to evacuate, you must remember the following:
- Pack a bag with important items in case you need to evacuate. Don’t forget to include medicines
- If advised to evacuate your home, move immediately to higher ground
- If possible, bring in outdoor furniture and move essential to an upper floor
- Turn off utilities at the main switches or valves. Disconnect electrical appliances
- Do not touch electrical equipment if you are wet or standing in water
- Do not walk through moving water. Six inches of moving water can make you fall
- Do not drive into flooded areas. If floodwaters rise around your car, abandon the car and move to higher ground if you can do so safely.
We can’t avoid disasters like flash floods and it might occur anytime and anywhere but we must always remember that our safety must come first. It is a must to understand and have deeper knowledge about events like Flash floods to know the things to do when in a certain situation. It is also important to listen to the news to be informed of the things happening around. Be alert and remember some of these helpful tips. Stay safe and focus!
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