FLASH FLOODS IN THE ILIŞUA BASIN

Flash Floods in the Ilişua Basin. The Ilişua Valley is a right tributary of the Someşu Mare Valley and has its spring in the south-western part of the Tibleş Mountains. It is a perennial river, and its maximum flow sometimes exceeds the national multi-anual average. One manifestation of this high flow is represented by two types of flash floods: the ones caused by heavy rainfall and the ones caused by the both heavy precipitation and the melting of snow. These two types of flash floods have specific characteristics not only in terms of causes but also in the happening, the impact area and the scale or proportions of damage. These features are further explained in the analysis of two flash floods that have taken place on May 12-17, 1970 and June 20-21, 2006. The occurence of these extreme hydrological phenomena in the basin and their impact upon nature, people and infrastructure makes the need of more hydrological survey a fact