رابطه بارش و رواناب حوضه هاي فاقد ايستگاه هاي هيدرومتري (مطالعه موردي حوضه آبريز صغاد)

ʹThe Relationship between Precipitation and Runoff Related to Basins that Lack Hydrometric Stationʹʹ (Case study: Soghad basin)

Having precise information about hydrometrics is essential so as to perform effects such as watershed management or activities related to urbanism, establishing transportation lanes and so on. Existing registered information gained by hydrometric and climatic stations has made it easy and typical to calculating the relationship between precipitation and runoff as well as estimating the maximum out put of runoff due to bottom lands and runoff, in most areas, but often this estimation in basins denuded of the hydrometric stations is problematic. The existence of cities and crossing the roads over the numerous flood channels in these areas has made necessary the estimation of the maximum output of runoff. This article studies flood waters of "Soghad basin", an arid basin which is lacking either hydrometric or climatic stations. The first step was to estimate the maximum precipitation in 24 hours using the adjacent ecological station and Thiessen polygon method and calculate the amount of runoff resulting from precipitation through experimental formulas. Final step was the comparison of dimensions of flood way in output point of the basin and the maximum debit of runoff resulting from a range of precipitations. The precipitations that might promote the discharge was then specified, those which might disturb normal condition of the flood channel, that is followed by floods.