Flood Modeling in a Coastal Town in Northern Colombia: Comparing MODCEL vs. IBER

Abstract

In Riohacha the La Niña, phenomenon generates intense rains with consequent serious flooding. To address this reality, MODCEL, a conceptual cell-based model, had been applied and calibrated in a previous project. In this research, we compare MODCEL with IBER, a well-known, physically based 2D hydraulic model. The purpose is twofold: (i) to illustrate how system schematization can be carried out in the two modeling frameworks, which is not a trivial task and implies several choices and assumptions; (ii) to point out the strengths and weaknesses of these two models in a comparative fashion. Here, IBER has been calibrated and validated with the same data used for MODCEL. MODCEL performs slightly better, both in calibration and validation possibly because of the low resolution of the topographic information, an essential element for IBER. Furthermore, in IBER it is not possible to represent adequately all the different hydraulic works spread across the town. MODCEL, in turn, is not easy to apply because it requires a deep insight into the actual behavior of the physical system and time-consuming schematization attempts where a deep experience is needed; furthermore, it is by far less user-friendly than IBER. In any case, the two models capture sufficiently well the behavior of urban flooding and its changes according to hypothetical interventions.

An integral assessment of landslide dams generated by the occurrence of rainfall-induced landslide and debris flow hazard chain

“…Iber is a free software that implements a family of bidimensional hydraulic mathematical models for the simulation of free surface flows in rivers and estuaries (Bladé et al, 2014;Pérez-Montiel et al, 2022). The equations are solved by the finite volume method on the grid nodes.…”

“…HEC RAS 2D is a model for unsteady flow based on the Navier-Stokes (Roldán et al, 2022); Iber 2D is a free model package for simulating unsteady free surface turbulent flow and transport processes in shallow water flows based on 2D Saint-Venant Equations (Bladé et al, 2014;Hafnaoui and Debabeche, 2021). Iber represents a better option for modeling rivers with more irregular geometries, especially when there is a special interest in the hydraulic behavior of the flow it has been successfully used in a wide range of applications, including impacts of dam breakage (Hoyos and Botero, 2019;Ruiz-Villanueva et al, 2020;Díaz-Salas et al, 2021;Pérez-Montiel et al, 2022).…”

Technological Advances to Rescue Temporary and Ephemeral Wetlands: Reducing Their Vulnerability, Making Them Visible

“…The software used to perform the simulation described in the following sections was IBER [23][24][25]. It is free software with a friendly interface, which makes it a relatively easy-to-use model, allowing rapid learning [37]. These characteristics make it an optimal tool to be used by managers and stakeholders in the field of environmental management.…”