Application of hydrodynamic estimated lag time formulas to the Sicily region.

ABSTRACT Name: Sameer Shakeel Khan Thesis title: Application of hydrodynamic estimated lag time formulas to the Sicily region. Supervisors: Gabriella Petaccia, associate professor, Phd, UNIPV, Department of Civil Engineering and Architecture; Giuseppe Barbero, professor, Phd, UNIPV, Department of Civil Engineering and Architecture. Simulating the runoff resulting from rainfall is a crucial process in assessing the consequences of severe flood events. This simulation is valuable for efficient water resource management and strategic planning. In regions prone to flooding, conducting a comprehensive hydrological study becomes imperative. The objective of the research is to investigate potential methods for estimating the response time of catchments, which can be influenced by various factors. Among these factors, lag time is often used as one of the key parameters. For the purpose of our study, we chose the Sicily region in Italy. There are 11 catchments selected for our study with a variety of soil types, land uses, geological formations and geographical positions. We examined catchments of various sizes, ranging from 10 km2 to more than 1600 km2, in order to challenge the approach used for achieving the results. Applying the definition of lag time, which refers to the time difference between the centroid of effective rainfall and the centroid of runoff, this study focuses on three interconnected concerns. 1. HEC-HMS model used to estimate the observed and simulated lag time. 2. Literature formula based on the 2D hydrodynamic watershed response 3. Empirical formulas In the first methodology the lag time values were measured using two methods The first approach involves using the Conservation Service Curve Number (SCS-CN) technique with HEC-HMS software, which relies on one parameter (CN) for calibration. The second method incorporates the Standard Clark method, resulting in a lag time based on optimized parameters. The other two methodology provides with list of equations to understand to what extent the lag time computed by the model can be considered as the hydrological response of the catchment. These approaches open the door to exploring innovative avenues in catchment hydrology research. The 2D hydrodynamic approach, incorporating formulas from the (Barbero et al. 2022) study, introduces four formulas integrating characteristic times linked to hydrodynamic responses to rainfall events. Utilizing kinematic wave theory and empirical observations, the conceptual model identifies relationships among variables. Literature formulas serve as benchmarks for comparing estimated lag time with the HEC-HMS model and the formulas proposed in this study This study conducted a comprehensive comparison of various estimation methods, evaluating empirical equations calibrated across diverse regions. Notably, large catchment areas demonstrated impressive results when comparing 2D hydrodynamic formulas with HEC-HMS estimates of lag time. The study suggests the need for future inclusion of new basins and events. ABSTRACT Name: Sameer Shakeel Khan Thesis title: Application of hydrodynamic estimated lag time formulas to the Sicily region. Supervisors: Gabriella Petaccia, associate professor, Phd, UNIPV, Department of Civil Engineering and Architecture; Giuseppe Barbero, professor, Phd, UNIPV, Department of Civil Engineering and Architecture. Simulating the runoff resulting from rainfall is a crucial process in assessing the consequences of severe flood events. This simulation is valuable for efficient water resource management and strategic planning. In regions prone to flooding, conducting a comprehensive hydrological study becomes imperative. The objective of the research is to investigate potential methods for estimating the response time of catchments, which can be influenced by various factors. Among these factors, lag time is often used as one of the key parameters.