Identifying Surface Runoff Distribution and Amount in Stream Basins: Ergene River Basin

Abstract

The undisputable significance of water resources necessitates solving problems related to the amount and distribution of water. However, existing methods and the outcomes obtained via these methods are continuously criticized and do not meet the expectations in terms of reliability. On the other hand, increasing need to plan water resources and lack of alternative methods to determine the water potential in areas where flow measurement does not exist make it impossible to evade dependency on these methods. With this purpose generated flexible, comprehensive and reliable runoff distribution map was formed on the basis of weighted overlay in parallel to impact degrees of effective parameters. The calibration of the obtained map was done on the basis of pixels based on both theoretical and empirical data. As a result of the analyses, it was seen that an accurate runoff distribution model that fully reflects the characteristics of the field can only be developed by calibrating it based on the real flow data obtained from remote sub-basins that are free from external interventions. It would be impossible to free the theoretical approaches from errors since these approaches are related to amount of water which has an active nature and interacts with factors that are beyond measure. As a result of implementing the method on Ergene River Basin, the sample basin, a surface runoff volume of an average183,45mm/year/m², i.e. a total of 2100000000m³/year ±2% was obtained for the basin and this result has at least 27% difference from the results obtained with existing methods.