النمذجة الخرائطية لمخاطر السيول في حوض وادي منى (مكة المكرمة)‎ باستخدام طريقة CN

Abstract EN

The research aims to estimate the size and risk of flooding in the basin of the valley of Mina by using soil conservation service method (CN).

This method depends on estimating the runoff and its risks on the covers and uses of land, the hydrological groups of soil, and the prior moisture of soil and rain.

Then, the covering layer of land and the hydrological groups of soil were integrated in the GIS.

Consequently, the values of curved numbers were derived from tables of this method according to the moderate state of soil moisture, and then, the raster calculator was used in the Arc Map program for applying the equations of depth, volume and peak discharge rates.

This method is considered to be the most widespread way for estimating the runoff in engineering studies and natural resource management projects in the United States and the rest of the world.

The importance of applying this method lays in the basin because of the Semi-holistic change of the natural covers of land; from natural to human uses of pilgrims which means that this method reaches accurate results in estimating floods and their risks in the basin.

The application of this method also enables planners and the decision-makers to follow all necessary ways to protect the pilgrims from the risks of flooding in the basin before, during and after the occurrence of floods.

The depth of flow at the level of the basin of rain storm 191 mm reaches 172 mm, the flow was 3.158.423 m3, and the peak discharge was 378.m3/sec.