Hydraulic Numerical Simulations of La Sabana River Floodplain, Mexico, as a Tool for a Flood Terrain Response Analysis

Rosanna Bonasia,Mackendy Ceragene

doi:10.3390/w13243516

Rosanna Bonasia, Mackendy Ceragene

Open Access

https://doi.org/10.3390/w13243516

Copy DOI

Abstract

The floodplain of La Sabana River, Guerrero State, Mexico, was subject to disastrous floods due to the passage of extreme weather phenomena. This is a situation facing many ungauged rivers in Mexico, as well as in other developing countries, where increased urbanization and a lack of monitoring systems make many inhabited areas more vulnerable to flooding. The purpose of this work is to provide a tool for determining the flood terrain response to flooding based on a hydraulic study. This methodology combines a hydrological analysis of the river basin with the floodplain hydraulic study for the precise identification of overflow points and the resulting flood levels. Results show that, for an ungauged river, hydraulic analysis is an essential tool for determining the main potential flood points and establishing whether the river has the capacity to contain floods. Specifically, it is shown that La Sabana River is predisposed to overflow long before the river reaches its maximum flow, even in correspondence with more frequent flood scenarios. This study shows a further application that a hydraulic model can have to improve flood risk preparedness for ungauged rivers of regions where other types of monitoring tools cannot be used.

Highlights

The sub-basin of La Sabana River, located in Guerrero, a state in southern Mexico, occupies an inhabited area characterized by strong economic and social contrasts
The disadvantage of applying hydrodynamic models is represented by the possibility of not being able to have sufficient spatial resolutions for the construction of the problem geometry
The high resolution of hydrodynamic models allows to study in detail the response to floods in highly critical areas, especially when monitoring systems are lacking or completely absent

Summary

Introduction

The sub-basin of La Sabana River, located in Guerrero, a state in southern Mexico, occupies an inhabited area characterized by strong economic and social contrasts. The floodplain of this river has been almost completely covered by urban settlements of a medium–low socio-economic level in the northernmost regions, and of a higher level approaching the beach, where Acapulco, the famous tourist Mexican destination, is located. The population increase in the last 20 years has determined the uncontrolled growth of settlements that stick to the riverbed, which has led to an increase in vulnerability of this area [1] Linked to this increase in urbanization is the fact that the Mexican territory loses hundreds of hectares of forest and jungle every year due to an intense deforestation [2,3]. This, along with other problems such as the increase in non-formal economic activities and hydro-meteorological effects caused by climate change, has caused an increase in the susceptibility of the area to flood events, especially in correspondence with the occurrence of extreme weather phenomena

Objectives

Methods

Results

Discussion

Conclusion