Field study on waves produced by HSC for coastal management

The aim of the present study is to improve the coastal risk management in the Bay of Naples, due to wake wash produced by high speed craft (HSC), establishing new navigation tracks in order to increase the safety of beach recreational activities and minimize possible environmental interferences. Wake wash analysis was performed by field measurements along Napoli-Ischia and Napoli-Sorrento-Capri routes, recording two different data sets: the effective route, by GPS installed onboard of several in service ships, and the produced wake wash monitored by several wavemeters, positioned in three critical points along the examined navigation tracks. Measured wake wash data have been subsequently compared with limit values suggested by International Rules, to establish some operational strategies and mitigative measures. On the basis of the obtained results, it was found the minimum distance between shoreline and navigation tracks had to be increased up to 500 and 1000 m for Napoli–Ischia and Sorrento–Capri routes, respectively. These prescriptions, furnished to the Civil Protection Department of Naples Province, have been already adopted by some Coast Guard recommendations, in accordance with the main Ship Companies operating in the Gulf of Naples.