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the ondjiva paradox | taming the flood
Flooding during the 2008 rainy season was so severe in the city of Ondjiva that thousands of ‘lucky’ chanas dwellers were evacuated to higher grounds while others were left stranded, cut off from any help for several days. The city’s basic infrastructure was not spared either, sanitation networks, utlity lines and power lines were affected even stopping from functioning all together in some parts of the city. The city of Ondjiva, in the southern portion of the Republic of Angola in Cunene Province near the boundary with the Republic of Namibia, is characterized by low lying flat terrain averaging a range of 1100 m
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Any flood mitigation measures has to carefully assess the impact on these water-dependent income generating and life sustaining activities
to 1115 m in elevation from the mean sea level. It falls between two huge river catchments and receives an annual rainfall of 800-900 mm/year during the October to April rainy season. The River Cunene to the west with a catchment area of around 94,000 km2 and River
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Cubango to the east with a catchment area of around 56,122 km2 are known as major perennial rivers. In between these two rivers a rather smaller river – a Cuvelai or natural wadi – receives storm runoff from the catchment between the Cunese and the Cubango and conveys the runoff southward towards Ondjiva. Before reaching Ondjiva city the river formed in the Cuvelai after heavy rain loses its defined corridor and spreads out onto surrounding flat terrain forming an inland delta of several wide and relatively shallow flood plain water courses called chanas. Ironically, these chanas constitute both a source of life providing water for people and livestock, aquifer recharge, and fishing and a threat flooding farms, roads, houses, and infrastructure of populated areas in the flood plain. Most of the population within the city depends on local agriculture for food and income including small farming activities, raising livestock, and fishing. These activities depend highly on the surface water runoff generated each year in several catchment areas, chanas and ponds. Any flood mitigation measures has to carefully assess the impact on these water-dependent income generating and life sustaining activities.
1 Ondjiva City location map 2 Flood devastation photos of low lying plains
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