DOI: 10.6084/m9.figshare.29856599
title: High-resolution digital surface and bathymetric model for the urban reach of the Duero River in Zamora, Spain

description: This dataset includes a high-resolution digital surface-river bathymetry model (DSRBM) of the urban reach of the Duero River in Zamora, Spain, which covers 5.4 km of the river channel and its associated 500-year floodplain. Several data collection approaches were combined to produce a detailed 3D representation of both terrestrial surfaces and underwater river bathymetry. The DSRBM combines airborne LiDAR data with 33 field-surveyed bathymetric cross-sections obtained using a single-beam echosounder (SBES) mounted on an aquatic drone. The strategic placement of the 33 cross-sections was determined using visual analysis of orthoimagery and Google Earth, with a focus on areas affected by fluvial islands, weirs, and bridges that affect water depths. As a result of this procedure, a KMZ dataset containing 33 cross-sections was generated. A subsequent bathymetric survey utilised this dataset as a reference and employed a 200 kHz SBES with a real-time kinematic global navigation satellite system (RTK-GNSS) to ensure precise mapping of underwater topography. The resulting bathymetric survey cross-sections, stored in ESRI Shapefile format, covered the 5.4 km urban reach of the Duero River through Zamora and were processed to create the digital river bathymetric model (DRBM).  <br> <br>Validation was conducted using independent survey methods, including a thorough ground-based validation survey that employed differential global navigation satellite system (GNSS) and inertial measurement unit (IMU) systems, which provided 3,407 control points across urban, peri-urban, and agricultural areas within the 500-year floodplain. This data was also stored in ESRI Shapefile format and produced derivative products, including vertical accuracy statistics for the DSRBM, point-wise residuals, error-distribution maps, and exceedance-probability maps. Further validation was carried out using SBES surveys, which provided 8,472 control points located within the urban reach of the Duero River. This validation data was stored in ESRI Shapefile format and provided vertical accuracy statistics for the DRBM and the aforementioned derivative products.  <br> <br>Through the processes of 3D Analyst raster conversion, masking, and mosaicking, all survey data were integrated into a composite DSRBM, which is available in GeoTIFF format with a spatial resolution of 1 metre. This DSRBM uses the ETRS89/UTM Zone 30N projection (EPSG: 25830) to provide the elevation data required for creating a 2D mesh. This mesh is the primary input for 2D hydraulic models, including HEC-RAS, TUFLOW, and Iber. The DSRBM can also be visualised and analysed using geographic information system (GIS) software, such as ArcGIS Pro and QGIS. The integration of terrestrial and bathymetric data enhances flood modelling by reducing errors in the assessment of flood depth and extent. This enhances the reliability of flood hazard mapping and risk management strategies, thereby increasing community resilience and facilitating more informed decisions in urban flood risk management.