Webmapping of Floods in the West of the Ivorian Coast

Abstract

To provide answers to the problem of the management of its coastal zone, Côte d’Ivoire has initiated a pooling of data collected on the coast to feed its environmental information management system. To this end, it was a question of creating an interactive platform for decision support for the development of this coastal zone. To achieve this objective, high spatial resolution raster data from 15 to 90 m from the Shuttle Radar Topography Mission and land cover vector data from 2017 were collected for processing in Websig software (QGIS 3.4, PostGreSql 10.5, PostGIS), published and displayed in Geoserveur for programming HTML, CSS and JavaScript codes in Atom. The results first made it possible to visualize the main issues in the interface, in particular, the rivers, the classified forests, the degraded forests, the intact forests, the housing and the industrial plantations and then to assess the risks of floods in Sassandra and San-Pédro. For overflow hazards 100 m beyond the shore, it is the houses, part of the forests and some bare soil that are submerged. As for the risks of overflowing 200 to 500 m beyond the shore, it is a large part of the housing, soils and intact forests that will be flooded. This tool must be made available to the final beneficiaries (users) by putting it online and listing it in the main search engines.