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Concerning the destructive effects and frequent damages of the flood in the country, studying the dimension and reasons of the flood of Neka city, as one of the greatest floods in the recent years and its preventive measures are objectives of this research.
By using direct observation method and statistical data and working on maps, this paper examines the dimensions of the flood of Mordad 18 (August) of Neka city with regard to the role of the existing conditions and geographical and natural structure of the region including the climate and rainafall, the basin’s height discrepancy, type of land, the rate of destruction of the forests and pastures, the river-beds deposits, coefficient of basin form, violation of the river limits, bridge status and river meander.
The results indicate the main role of inhabitants of the region in neglecting to perserve the biological harmony. The geographical structure of the natural conditions is also the contributing and intensifying factors which brought about the Neka flood.