Abstract

Urban drainage systems are facing increasing challenges due to climate change, urban growth, and the need for more sustainable water management. To address these issues, the Digital DRAIN project has developed an open-source tool that integrates different models within a GIS environment to analyse the performance of drainage systems. The tool helps assess both water flows and pollution, while also supporting the design of sustainable solutions and adaptation strategies. Delivered as the QGIS plugin IberGIS, it provides an accessible framework to improve urban water management and enhance resilience against floods and environmental impacts.

Abstract

Large wood plays a vital role in river systems, shaping habitats and supporting biodiversity. However, during floods, large wood transport can threaten infrastructure and communities. Traditional flood models often overlook wood material, despite its natural presence in rivers. To address this gap, the calculation module Iber-Wood was developed and integrated into the Iber model. Iber-Wood combines the Eulerian Iber 2D hydrodynamics with a Lagrangian model to simulate wood as dynamic elements. The model accounts for wood-flow-sediment, wood-wood, wood-infrastructure, and wood-terrain interactions, using two-way coupling. It has been validated with flume experiments and applied to various real rivers using field data. Applications include studying wood-sediment-flow dynamics and bridge-related wood accumulation. Though deterministic, Iber-Wood enables scenario testing and hypothesis exploration for complex wood dynamics.

Abstract

Iber is a two-dimensional hydraulic model for the simulation of free surface flow in rivers and estuaries, and the simulation of environmental processes in fluvial hydraulics. Since the release of the first version of Iber, which included a hydrodynamic calculation engine fully coupled with sediment transport processes and turbulence, it has evolved to become a free surface flow modelling tool for highly complex environmental processes. This document presents the developments made for version 3, specifically, for the new calculation module for the simulation of shallow non-Newtonian flows called IberNNF. The shallow water equations are solved using an ad-hoc numerical scheme focused on the simulation of this type of flow in nature (e.g., steep slopes, irregular geometries). The graphical user interface (GUI) has been adapted to the module's new features to achieve a simple and user-friendly workflow.

Abstract

Approximately 70,000 Spanish off-stream reservoirs, many of them irrigation ponds, need to be evaluated in terms of their potential hazard to comply with the new national Regulation of the Hydraulic Public Domain. This requires a great engineering effort to evaluate different scenarios with two-dimensional hydraulic models, for which many owners lack the necessary resources. This work presents a simplified methodology based on machine learning to identify risk zones at any point in the vicinity of an off-stream reservoir without the need to elaborate and run full two-dimensional hydraulic models. A predictive model based on random forest was created from datasets including the results of synthetic cases computed with an automatic tool based on the two-dimensional numerical software Iber. Once fitted, the model provided an estimate on the potential hazard considering the physical characteristics of the structure, the surrounding terrain and the vulnerable locations. Two approaches were compared for balancing the dataset: the synthetic minority oversampling and the random undersampling. Results from the random forest model adjusted with the random undersampling technique showed to be useful for the estimation of risk zones. On a real application test the simplified method achieved 91% accuracy.

Abstract

Iber es un modelo numérico bidimensional de simulación de flujo turbulento en lámina libre en régimen no-permanente, y de procesos medioambientales en hidráulica fluvial. Desde el lanzamiento de la primera versión, que incluía un motor de cálculo hidrodinámico completamente acoplado con procesos de transporte de sedimento y turbulencia, Iber ha ido evolucionando hasta convertirse en una herramienta de modelización de flujo en lámina libre de procesos ambientales de elevada complejidad. En este documento se presentan los desarrollos realizados para la versión 3, donde los avances son principalmente en cuatro líneas de investigación: un nuevo módulo de drenaje urbano, un avance significativo en las capacidades del módulo de hidrología, un nuevo módulo de erosión de suelos, y un nuevo módulo para el cálculo del transporte de sedimentos considerando material no uniforme (mezclas). Asimismo, todos los trabajos han ido acompañados por una tarea transversal de mejora de la interfaz, tanto para los módulos ya existentes, como la creación de nuevas ventanas y menús para los nuevos módulos con el objetivo de mejorar todo el flujo de trabajo.

Abstract

Permeable pavements are a common solution for wearing course layers in roads and urban areas. They are composed by highly porous materials with permeability several orders of magnitude above of the natural terrain. This work presents, on one hand, the experimental characterisation of the hydraulic behaviour of a permeable asphalt concrete wearing course layer and, on the other hand, the development and validation of a two-dimensional coupled hydraulic-hydrological distributed numerical model to reproduce the effect of the infiltration in the rainfall-runoff transformation and in the overland flow propagation processes. Experiments show linear and potential trends for permeability-hydraulic head relations when considering constant and variable hydraulic heads, respectively, reaching permeability up to 0.04 m/s for 1 m of hydraulic head. Experiments are reproduced numerically by incorporating new infiltration formulas, which consider the infiltration rate as a function of the hydraulic head, and a specific numerical scheme for properly dealing the mass conservation when negative values of the water depth may occur numerically due to high infiltration rates. This two-dimensional coupled hydraulic-hydrological distributed numerical model is a validated tool for simulating the effect of permeable pavements not only in the rainfall-runoff process, but also for the overland flow propagation.