Reconstruction of Masuleh Debris Flow Initiated by Heavy Rain Fall

Landslide and flood are natural disaster which can create tremendous lose of life and properties. The combine occurrence of these events can create debris flow. Due to the repetition of debris flood in different locations of northern part of the country (Neka, 1378, Kolastan, 1380, and 1384), and tremendous destructive power of this natural event, it is essential to assess the effective parameters in development of debris flow. In this paper the condition of masouleh debris flow is reconstructed to assess the effective parameter and suggest possible remedial measures. After a short and intense rainfall a huge flood along with considerable amount of particles ranging from silts to boulder contents striked masouleh town and obstacled the main bridge. This event diverted the debris flood towards the town and caused lose of life and properties. About forty percent of sub basin area is affected by landslides. The rock slides have affected 25.7 percent of the area at the southern part of basin. Various methods were used to estimate the required discharge flow to carry out the material. The optimum method was chosen according to study area condition. The filed investigations clearly demonstrated the river cross sections of upstream can not permit the huge boulders to cross and the big boulder which obstacle the main bridge has been removed from landslide area at downstream at the vicinity of the town.