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The bathymetric survey of the Grand Canal was carried out in 2013 as part of the RITMARE project, using a Kongsberg EM-2040 dual-head multibeam echo sounder installed on the CNR-ISMAR research vessel *Litus*. The system acquired high-resolution data (up to 800 beams per sweep) along parallel transects, covering the main canal and surrounding areas. Positioning was ensured by the integrated Seapath 300 GNSS system, with real-time differential corrections. The speed of sound in water was measured using Valeport SVS sensors mounted on the hull and vertical profiles collected with an AML Oceanographic Smart-X probe.

Data recording and supervision took place in real time using Kongsberg SIS software, while the post-processing phase included attitude correction, cleaning of anomalous data, time alignment and creation of the digital bottom model. The final data were converted into standard formats (XYZ, GeoTIFF) and referenced in the UTM WGS84 zone 33N (EPSG:32633) system. The entire process was carried out following standardised quality control and internal documentation procedures of CNR-ISMAR.