Investigation of the Maximum Flow Trends and Their Impact on Risk Levels of Spillways

Abstract

Abstract. Flood discharge capacity is used as input parameter for spillway design, and it is sensitive to climate change effects. One of the main aims of climate studies is seeing the result of the variability of climatic parameters on water structures. So, the observed maximum flow must be evaluated by the view of trend analysis of maximum flow data. At the same time, changing the risk levels of spillways must be evaluated by risk analysis using same data. Thus, the relationship between maximum data flow and flood risk can easily be understood. Based on the updated observation data, new or existing spillways can be designed or rehabilitated accurately. Ten selected dams in Turkey are studied for evaluating the aim, while Mann-Kendall and Spearman's Rho tests are used for investigating trends. The MFOSM (Mean Value First Order Second Moment) and AFOSM (Advanced FOSM) methods are used for analyzing the risks. Using maximum flow parameters, the existence of trends and safety level of spillways are reported for selected dams. Results show us the process of observation of the updated maximum flow data, and its effect on risk levels for dam safety is crucial for prediction and prevention of the flood damages.