Bathymetric map of the Rimini outport (2024)

This bathymetric survey is part of the pre-construction monitoring of the "Rimini Outer Harbour - Completion of Offshore Defense Works" project, which concerns marine biological components, as indicated in the request for additional information submitted by the Ministry of the Environment and Energy Security and received by the Municipality of Rimini under reference number 0094957/2024 of 14/03/2024. To this end, geophysical surveys were carried out using Single Beam sonar and Side Scan Sonar for shallow waters, with visual and sample checks of acoustic targets, to verify the absence of Cymodocea nodosa and other phanerogams in the project area and in the vicinity within a 500 m radius of the port area.

The sonar survey was performed on 19/06/2024, from 8:17 to 10:37 UTC. Given the shallow depth of the area, a Lowrance HDS Live shallow water SSS model was used with a 16-channel WAAS/EGNOS class DGPS positioning system with a frequency of 10 Hz and an Active Imaging™ 3-in-1 transducer (CHIRP/Side/Down). The data was corrected for the offsets between the GPS antenna and the transducer and the transducer immersion. The acoustic images were processed and mosaicked using ReefMaster 2.0 software, which also allows for the analysis of the back scattering of the built-in 200 kHz Single Beam CHIRP sonar.

The survey was conducted in calm to almost calm sea conditions and at relative high tide with an almost constant sea level; therefore, during the time interval the astronomical tide varied by very few centimetres (0.47-0.50 m MLLW, mean low level water, which in this area corresponds to approximately -0.40 MSL, mean sea level). 

The acoustic measurements were corrected based on the astronomical tide to obtain the final bathymetry, referred to the mean sea level.

Survey date 2024-06-19

File format: Arc/Info ASCII Grid & ESRI Shapefile

Projection: EPSG:32633 - WGS 84 / UTM zone 33N

Tide datum: mean sea level

Data acquisition: Sonar Lowrance HDS 7 single beam 200 kHz

Data processing: Kriging interpolation