Mapping the continental shelf calls for accurate surveying covering geology, sedimentology, habitat mapping and modelling turbulent physical phenomena. In order to have a multibeam echosounder powerful enough to carry out continental shelf mapping, the decision was made to install a Kongsberg EM2040 echosounder on the Le Suroît, replacing the now-obsolete EM1000 echosounder. The EM2040 operates in the 200, 300 and 400 kHz ranges at a maximum depth of 200 m for a maximum swath of 200 m. Mechanical installation took place at the Piriou shipyards in Concarneau from July 9-22, 2013. Sea trials took place in the Iroise Sea and the Brest Roadstead from July 24-26, 2013. The proper functionality and performance of every aspect of the equipment was demonstrated during test surveys.