Capturing Floodwaters Can Reduce Flooding and Combat Drought!
Why black people should be returning to Africa and building for the future! Although most articles on line claim Africa is the most vulnerable the truth is it is the safest place on the planet when it comes to everything needed to survive climate change. The additional growth of solar power and wind as well as construction of desalinization plants that don't require the removal of old infrastructure makes it the go to spot for educated investors in the future! Across Africa, as in other continents, flooding may arise locally within built-up areas from debris blocking streams and from overflowing sewers. Nevertheless, many cities are flooded by major rivers that carry extreme flows of water from surrounding regions and even distant mountains. The causes and impacts of floods, human vulnerability, possibilities of risk reduction and political and management responsibilities vary from the household and community levels up to sub-continental hydrologic systems and the global climate system. Yet what in the past was deemed a negative in a climate changed world this excess water will be a great positive.
Different types of flooding can affect African cities: pluvial flooding from torrential rain that reaches the ground more quickly than it can infiltrate or flow away downslope; groundwater flooding where the normally subsurface water table rises to the ground surface and water emerges into basements and ground-level rooms in buildings; flooding from overflowing drains and channels that have insufficient capacity to evacuate all the water which flows into them; flooding from major rivers that have brought huge volumes of water from areas, maybe many tens, or even hundreds, of kilometers upstream; or shoreline inundation from large lakes or seas during storms. When floodwaters recede, affected areas are often blanketed in silt and mud. This sediment can be full of nutrients, benefiting farmers in the area. Famously fertile flood plains like the Mississippi River valley in the American Midwest, the Nile River valley in Egypt, and the Fertile Crescent in the Middle East have supported agriculture for thousands of years. Yearly flooding has left millions of tons of nutrient-rich soil behind.
However, the actual height and extent of any given flood is determined by the nature of the ground surface, the dimensions of the channels or coasts along which flood flows develop and by local obstructions to water movement. It is possible to change these conditions through human actions that benefit the region and bring great rewards. Most environmental issues, including flooding, are interconnected. Increasingly, hydrologists are investigating how rainfall and river flows in Africa, teleconnections can help to establish the effects of land use and land cover changes in one part of a river basin on water availability for irrigation or urban use, or on river channel capacity for flood waters, in another area further downstream. Understanding what can be done about flooding involves comprehending the inter-relations between both geophysical processes and human drivers, risks, and vulnerabilities. Capturing Floodwaters Can Reduce Flooding and Combat Drought! If climate change is likely to unleash more floods in Africa, why not try to capture that water and send it to where it’s needed most. All analysis must focus on the highest levels of streamflow likely to accompany any big storms. Harvesting those high-water flows, helps mitigate flood risk while growing groundwater supplies. to simulate streamflow and climate conditions under different emissions scenarios, statistical methods are used to account for human actions like irrigation and reservoir operation. Then prioritize regions where investing in structures to divert floodwaters would make the most sense.
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