Characterization of a Flood Event through a Sediment Analysis: The Tescio River Case Study

Abstract

This paper presents the hydrological analysis and grain size characteristics of fluvial sediments in a river basin and their combination to characterize a flood event. The overall objective of the research is the development of a practical methodology based on experimental surveys to reconstruct the hydraulic history of ungauged river reaches on the basis of the modifications detected on the riverbed during the dry season. The grain size analysis of fluvial deposits usually requires great technical and economical efforts and traditional sieving based on physical sampling is not appropriate to adequately represent the spatial distribution of sediments in a wide area of a riverbed with a reasonable number of samples. The use of photographic sampling techniques, on the other hand, allows for the quick and effective determination of the grain size distribution, through the use of a digital camera and specific graphical algorithms in large river stretches. A photographic sampling is employed to characterize the riverbed in a 3 km ungauged reach of the Tescio River, a tributary of the Chiascio River, located in central Italy, representative of many rivers in the same geographical area. To this end, the particle size distribution is reconstructed through the analysis of digital pictures of the sediments taken on the riverbed in dry conditions. The sampling has been performed after a flood event of known duration, which allows for the identification of the removal of the armor in one section along the river reach under investigation. The volume and composition of the eroded sediments made it possible to calculate the average flow rate associated with the flood event which caused the erosion, by means of the sediment transport laws and the hydrological analysis of the river basin. A hydraulic analysis of the river stretch under investigation was employed to verify the validity of the proposed procedure.

Forcing for a Cascaded Lattice Boltzmann Shallow Water Model

“…It has been extensively applied in different fields, such as turbulent flow, multiphase flow [21], flow in complex geometries [22], in porous media [23], and thermal flows [24]. However, it is not so common to use the LBM approach to simulate large scale hydraulic problems, such as flooding events [25], dam breaks [26], and propagation of tsunamis. The LBM applies an algorithm in which particles move on a Cartesian lattice and collide at lattice nodes.…”

Coping with Extreme Events: Effect of Different Reservoir Operation Strategies on Flood Inundation Maps

“…The propagation in the channel of the discharge outflowing from the dam was performed using the one dimensional (1D) code HEC-RAS [25] in steady flow conditions. HEC-RAS has been widely applied for hydraulic modelling (e.g., [26][27][28][29][30]) and its trustworthy has been proven by many scholars (e.g., [31]).…”

Characterization and frequency analysis of flooding solid flow in semi-arid zone: case of Mekerra catchment in the north-west of Algeria

“…The main objective of the solid transport data analysis is to determine the origin of the transported sediments, through the analysis of concentration curves as a function of flow rates (C = f(Q)). Several studies have focused on the study of transport and quantification of solids (Nones 2019;Mrokowska and Rowinski 2019;Di Francesco et al 2016;Tabarestani and Zarrati 2015;Vrolix and Pissart 1990). In Algeria, several researchers have evaluated the sediment transport associated with the floods in the country.…”