Bathymetry and lakebed characterization of Bracciano lake (Lazio region, central Italy)

Bracciano is a volcanic lake located in central Italy, close to Rome, serving as the primary source of drinking water for the city. It is included in the Bracciano-Martignano regional natural park and is susceptible to the impact of various human activities that interact with its lakebed morphology. The latest bathymetric chart of the lakebed was published in 1969 and showed the overall morphology of the bottom with 5 m spaced isobaths. This paper presents an original morpho-bathymetric dataset, acquired by means of multibeam echosounders, within the Italian Geological Mapping Project at a 1:50,000 scale (CARG project). The new mapping of the Bracciano lakebed allowed the identification with extreme detail of two orders of submerged terraces, channels and landslides, and several pockmarks often associated with rising fluids. Moreover, a distribution map of lakebed sediment was produced by merging the geophysical dataset with ground-truth data.