The Geoenvironmental Cartography and Remote Sensing Group (CGAT) del Cartographic Engineering, Geodesy and Photogrammetry Department(DICGF) of the Universitat Politècnica de València (UPV), together with the ETSI Geodesic, Cartographic and Topographic ETSI(ETSIGCyT), has elaborated this map of the flooding depths in l’Horta Sud after the episode of October 29, 2024. This work, developed as a volunteer actThe aim is to provide useful information for the affected populations, to better understand the nature of the event and to provide a key tool for the management of future floods. It has been created by CGAT and DICGF researchers, as well as by ETSIGCyT students who enthusiastically wanted to make a useful contribution from the field of geomatics engineering to the serious problems caused by floods.
The work is based on measurements taken in the field during the months of November and December 2024 and part of January 2025 and what is now presented is a preliminary result(updated as of 01/21/2025) with part of the flooded areas still to be mapped. The red polygon surrounding the area represents the current survey boundarynot the limit of the flooded area.
The work has been developed in three phases: (1) field survey, (2) generation of the water sheet and maximum draught models and (3) generation of the final viewer.
(1)Field survey
The following have been taken5,097 points (updated as of 01/21/2025) used a topographic sight resting on the wall where the signal was and thus measured the depth reached in that place by the water. Its location has been done using the GNSS sensor (GPS) of mobile devices, the cartographic base Open Street Maps (OSM) and orthophotographs of the Institut Cartogràfic Valencià (ICV).
(2)Generation of water depth and maximum water depth models.
The local depth data have been interpolated to estimate the depth over the entire flooded area. Built-up areas have also been masked leaving those spaces without information. Two cartographic products are provided in the viewer: (1) the height of the sheet of water (covering both built-up and non-built-up areas) that helps us to recognize the main alignments of the main flood currents and (2) the height of the masked sheet of water that presents the flooding only in the areas without buildings (streets, squares, open field, ….), where it has really occurred.
(3)Generation of the viewer.
A viewer has been created to allow any user to access the final results. The viewer has an active layer that allows recognition of the gazetteer and the ICV orthophoto prior to the flood (2024) and also the street map data (Open Street Maps). The draught information is represented by a range of colors (colder indicates shallower and warmer indicates deeper and warmer indicates deeper draughts), the legend of which is always displayed. In any case, the user can click on any point and the viewer derives the result of the maximum depth at that location.
This information can be accessed through the following link https://dana2024.upvusig.car.upv.es/ and can be accessed from both cell phones and computers. The application is available in Spanish, Valencian and English.