Aghios Nikolaos Port - Zakynthos Island

The Aghios Nikolaos Bay, in the northeast coastline of Zakynthos Island, is named after the homonymous small island that is located just at his entrance. Its presence forms two different gateways towards the bay and the respective port facilities, the north and the south one. The existing quay walls serve the ferries that connects north Zakynthos with Pessada in Cephalonia during the summer, the excursion boats that perform the routing towards the famous beach of Navagio and, lastly, the fishing and tourist boats that pass.

However, the existing port facilities present a series of important functional problems due to the underdeveloped external harbour works, which cannot protect the basin, effectively, from northeast and southeast waves that affect the area. Thus, and in order to upgrade the existing infrastructure, the Prefecture of Ionian Islands assigned the design of new harbour works that resulted in three different layout.

The review of those layouts, considering the prevailing wave conditions both in the gateways of the bay as well as in the basin, required the preparing of a wave disturbance study by implementing the related numerical model simulations. The study was realized in 2006 by CNWAY, on behalf of the consultant engineer-designer of harbour works.

The results of the study showed that the proposed works in review did not offer good protection το the basin and to the quay walls, when strong NE and SE winds blow in the area. The use of absorbent quay walls improves to some degree the wave conditions but it does not eliminate the problem permanently. Thus, according to the results of the numerical model simulation and in collaboration with the designer of harbour works, a new layout was proposed with longer breakwaters, at the entrances of the bay and absorbent new quay walls along the coastline. This layout was proven to be more effective in maintaining the wave disturbance, inside the basin, in acceptable levels.

Study facts:

• Estimation of offshore wave characteristics using JONSEY model from Seaworks1 marine software suite
• Simulation of wave disturbance by the numerical PORTRAY from Seaworks3 marine software suite
• Three dimensional display of sea bed using AutoCad Civil3D from Autodesk, square mesh dimension 10mx10m
• Implementation of simulation for eight (8) layouts, existing and seven new proposals
• Examination of three (3) wind directions, northeast (wind intensities of 11bf) east (wind intensities of 11bf) and southeast (wind intensity of 7bf)