Natural Disasters Preventing Flooding Flood Prevention Flood Prevention

Natural Disasters Preventing Flooding

Flood Prevention

Flood Prevention

Flood Prevention Photo courtesy of Airwolfhound (@flikr. com) – granted under creative commons licence - attribution

How a Dam works to prevent flooding Water from a large body water may build up and overflow causing a flood in extreme weather. A small amount of water can flow through to stop the water overflowing. This water that is allowed through usually flows into a river. Photo courtesy of Airwolfhound (@flikr. com) – granted under creative commons licence - attribution Dams can be built to prevent this. A Dam is a large wall-like structure that acts as a barrier to stop or restrict the flow of water.

Forces A type of dam called a Hydroelectric Dam also filters this water through to create electricity from the movement of the water that travels through the Dam.

Natural Dams Photo courtesy of Airwolfhound (@flikr. com) – granted under creative commons licence - attribution

Designing a Dams require a lot of hard work and design carried out by a large group of people to make sure they work properly. Why do you think it is important lots of care is taken over there design? Civil engineers are responsibility for designing the structure of the dam. They carry out mathematical calculations to model the dam and the effects of the forces on them.

Forces A force is an outside influence that can cause movement or pressure. For example pushing is a type of force. What forces may need to be thought about when designing a dam?

Forces The main force is the water in the reservoir pushing on the Will this effect the material used to create the Dam? dam. What sort of material will be best to make the Dam from? Think about video clips we have watched on flooding and how powerful water is, How would it feel to have a lot of water pushing against you if you were a Dam wall? If the material the Dam is made from is not strong enough, the pushing force from the water may cause the Dam to break.

Forces What can be done to help prevent the force of the water Some of the water in a hydroelectric Dam breaking the Dam? can be let through in one or a few places of the Dam to lower the amount of water in the reservoir and reduce the force as can be seen in the images.

Forces Engineering geologists also look for the presence of any faults in the rocks surrounding the dam in common earthquake regions and consider whether the force from an earthquake could cause the fault to rupture. Another force is also the weight of the Dam itself. If the Dam is very heavy, the force of gravity may act upon the Dam to make it fall down if it is not designed well.

Forces Some Dams also allow traffic to travel along them like a bridge which adds weight onto the Dam. What type of force is this? The dam needs to built of a strong enough material to hold this weight.

Flooding A flood is an overflow of water that covers land that is usually dry. Some floods develop slowly, while others, such as flash floods, can develop in just a few minutes and without any signs of rain. Floods can be local, impacting a neighbourhood or community, or very large, affecting entire river basins. Photo courtesy of U. S. Geological Survey, The U. S. Army, DVIDSHUB(@flikr. com) – granted under creative commons licence - attribution

Task- Design your own Dam Your task is to draw and design your own Dam. Use the information on the slides to design a Dam that will withstand all the forces it may be faced with. Label your Dam and explain underneath your diagram what you have done to make sure your Dam is strong enough to do it’s job. For example, what material have you used and why? What have you done to stop too much force from the water?