March 6, 2017

Design of Coastal Protection Works

Several experiments have been carried out to assist the design of the best technical solutions regarding both the current and future sea levels. The tests involved both hard and soft technical solutions, i.e. offshore breakwaters and beach replenishment. The following figure shows the effects on hydrodynamics of a technical (hard) solution for Kamari (Santorini) for the present sea levels/wave regime.


Kamari (Thira): Modeled wave and wave-induced current fields following construction of four ‘hard’ structures (submerged breakwaters (-0.4 m) at water depth of 4-5 m, with a length of 80 m and spacing of 50 m) under equivalent extreme mean waves from the eastern sector


As a ‘soft’ measure to augment the present beach, experiments/estimations showed that in order to extend seawards the beach for about 15 m the sand volume required (size d50 > 0.6 mm) is expected to be about 101 m3/m, followed by an initial beach replenishment width of 26 m, initial bed slope of 1:4 and berm height of 1.5 m.

In addition, the case of combining ‘hard’ and ‘soft’ technical works was examined. The figure below shows the expected coastline evolution and changes in the hydrodynamic regime of Masouri beach in Kalymnos, after the construction of a breakwater accompanied with beach replenishment. Results show that under such a case, beach protection (especially of the southern eroded part) is expected to be every effective, followed by coastline evolution and stabilization of the beach by several meters.


Μαsouri (Kalymnos): Simulations of the waves and wave induced currents (left) and coastline evolution trends following the combined impact of a ‘hard’ and a ‘soft’ measure (construction of breakwater and beach nourishment)

ERA Beach Partners - Funding