31-08-2012, 04:50 PM
FLOODS
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What are floods?
A flood is a natural disaster brought about by a combination of factors: Physical and climatic. A flood is the rising of a body of water and its overflowing onto normally dry land. Floods can be caused by heavy rains that pour too much water into rivers and other waterways. Making these natural channels unable to carry all the water. Rising water flows over or breaks the banks to the waterways causing the surrounding land to be flooded.
Causes
1. Floods are formed when big waves are rolled on normally dry places.
2. Rain can also cause floods when it rains more than the land can’t handle.
3. Floods can happen after a hurricane, such as after hurricane Katrina it flooded the neighborhoods in New Orleans.
4. Floods are one of the most common hazards in the United States, however not all floods are alike.
5. Additionally, floods can be local, impacting a neighborhood or community, or very large, affecting entire river basins and multiple states.
6. Flash floods often have a dangerous wall of roaring water carrying rocks, mud and other debris. Overland flooding, the most common type of flooding event typically occurs when waterways such as rivers or streams overflow their banks...
Vulnerability
Why Flood Vulnerability?
Human population world wide is vulnerable to natural disasters. In recent years the impacts of floods have gained importance because of the increasing amount of people who are exposed to its adverse effects. The aim of vulnerability studies is to recognize correct actions that can be taken to reduce vulnerability before the possible harm is realized. FVI is a powerful tool for policy and decision-makers to prioritize investments and makes the decision making process more transparent. Identifying areas with high flood vulnerability may guide the decision make process towards a better way of dealing with floods by societies?
What are the effects on the environment from the flood?
Because of the floods the water is pushing away all of the trees. All of the rocks are disintegrating of the waters current. The flooding has blocked up the draining making the sewers overload, which is how water born diseases, start to spread. Also the flooding it has destroyed the crops making it hard to find food, for all the people. Because of the flooding is making the building collapse away, the toxic paint, pesticide and gasoline can be released to the water harming the environment. Non-tolerant species can die from suffocation.
Impact of floods economic?
Floods not only damage property and endanger the lives of humans and animals, but have other effects as well. Rapid runoff causes soil erosion as well as sediment deposition problems downstream. Spawning grounds for fish and other wildlife habitat are often destroyed. High-velocity currents increase flood damage; prolonged high floods delay traffic and interfere with drainage and economic use of lands. Bridge abutments, bank lines, sewer outfalls, and other structures within floodways are damaged, and navigation and hydroelectric power are often impaired. Financial losses due to floods are commonly millions of dollars each year.
Better construction practices?
According to the present invention above, it is possible to semi-permanently maintain safety at the basic lower portions of the structure as the vertically interlocked blocks lower like a shutter to block caved-in spaces when the basic portions of the structure are caved in by waves or flowing water. The retaining wall construction system for preventing tsunamis and flood damages includes hexagonal multi-layered interlocking blocks. the structure of the retaining wall in a stepped type, a type in which the center of gravity moves downward, a buttress type, a flowerbed type, a column hybrid type or the like are geometrically and structurally very safe so that damages due to natural disasters such as floods, tsunamis, earthquakes or the like may be effectively prevented.