Development in Flood Zone :: Population, Urban Areas

The world population has more than doubled in lastly 50 years (from 2.52 billion in 1950 to 6 billion in 2000). Moreover the United Nations (1999) estimate that 97% of growth is taking role in less developed countries, with Africa as a fast developing Area. Cities such as Bombay, Calcutta, Karachi, Jakarta, Nairobi, Manila, Lagos and Cairo atomic number 18 examples of rapid human concentration. This makes the circulating(prenominal) planning strategies insufficient and ineffective (if they even exist). Consequently, slums and squatters and informal settlements in those cities are the expression of a marginalization of a big and growing wander of city dwellers (Sietchiping 2000). It is undeniable that landuse is continuously changing. The speed of urbanization, of forest clearance and of clownish under drainage and ploughing up of natural grassland have change magnitude flood potential (Ward 1978). Usually informal settlements are located on vulnerable and unbuilt bailiwick s such as deep valleys (Nairobi), river banks (Bombay), abandoned waste cast out (Manila) or dangerous slopes (Yaounde). They are known as catastrophe given up areas (floods, landslides and health hazard). It has originated from difficult problems of housing, immigration rates, politics, physical planning, landlessness, and employment in urban areas (Sietchiping 2000). Many build their homes and grow their food on river flood plains intowns and cities (Douglas 2008). downpour along some of the low-lying floodplains adjacent to major rivers mountain be both widespread and long in duration (Zillman 1999). In the plate of the GangesBrahmaputraMegna river system in Bangladesh, 110 million people are relatively unprotected on the floodplain of southern Asias close to flood-prone river system (Smith 1996 pg 258). But risks are also great for settlements in littler river basins subject to sudden flash floods and along low-lying shorelines where storm surges associated with cyclones can produce sea flooding of several meters in depth (Zillman 1999).Davis and mansion (1999) argue that poverty can drive people toward settling and on the job(p) in precarious locations such as unstable riverbanks in domain areas. Of Asias great population, 89% of the gainfully employed population of Thailand, 73% of that of Korea, 70% of that of Burma, 69% of that of Philippines and 67% of that of India is engaged in agricultural work (Bureau of Flood Control 1950). The alluvium of river valleys and river deltas provide the most suitable area for agriculture. The flat topography of these areas lends itself admirably to farming (Bureau of Flood Control 1950). In