Solhan Creek in Basin (Bingol) flood and torrent analysis

Natural disaster is defined as dangerous and generally far-searching incident which occur in a great extent or completely beyond control of human and can cause loss of life and property. The first characteristic of disaster is that it happens beyond control of human, so it is natural; the second it causes loss of life and property, the third it happens at short notice, lastly if it starts, it cannot be hindered by human. Resulting substantial damages in both residential and rural areas and varying in terms of severity and frequency, flood and overflow causes loss of life and property on a large scale recently, notably in our country and in the world. Our study area, between 2001- 2009, 18 overflow incidents. Changes in meteorological conditions in the long transform overflows into disasters. Across Turkey, basic reasons of this are geographical position, uneven orography and vegetation. Economically, it caused 100 million dollars loss between 1974 and 2009 and it still continues. It is not possible to state that floods occur only as the result of meteorological formations. Particularly in countries like Turkey in which urbanization is high; increasing human activities cause hydraulic and hydrologic imbalance, as a result of it floods take place and cause loss of life and property. Progressive settlement inside river basin, changing structure and usage of terrain, incorrect and intensive usage of land, destruction of forests and pastures bring about bigger and more frequent overflow disasters. In "Solhan Creek in Basin (Bingöl) Torrent and Flood Analysis" study, first of all the definition and the importance of flood and previous studies are discussed. Then the effective factors on floods are discussed and in the next section the techniques to analyze overflows are revealed and these techniques are evaluated and interpreted in the scope of Solhan Stream Basin. Thereinafter the risk potential of flood and overflow is clarified by using multi criteria decision analysis. In this study by using geographical information systems, morphometric modeling of studied basin has been presented, geomorphologic and geomorphometric indexes, which affect overflows, are revealed separately. Digital elevation model, prepared on topographic maps, is used as input data to basin flow model for hydrologic and hydraulic modeling. Consequently, for Solhan Stream Basin, potential areas that are under overflow risk are determined by using parameters which influence flood and overflow. Key Words: Natural Disaster, Flood, Overflow, Geomorphometric Index, Method,Remote Sensing, Multi Criteria Decision Analysis, River Basin