Sand beach nourishment: Experience from the mediterranean coast of Israel

Beach nourishment along the Mediterranean coast of Israel represents a new approach to mitigate coastal erosion by adding suitable sand to threatened beaches. This 'soft' solution has become more environmentally and economically acceptable than traditional 'hard' solutions, such as seawalls, revetments, detached breakwaters and groins. Beach nourishment projects have been implemented on the Israeli coast north of Ashdod Port (2011), north of Ashkelon Marina (2015) and in the south of Haifa Bay (2016-2017). The performance of these projects was analyzed and compared with nourishment projects along the Mediterranean beaches of Italy, France and Spain. Despite a lack of detailed documentation on most of the European nourishment projects, they proved more durable than the Israeli projects, which were compromised when the imported sand eventually washed offshore. Key factor for the Israeli projects' failure include the unsuitable morphology of the beaches; insufficient unit sand volume (m3/m-volume of nourished sand per meter of the beach length); and imported sand that was too fine versus native sand. The unique physical conditions of the Israeli coast specifically, its open shelf and straight coastline subject to relatively high waves with a very long fetch-also contributed to the poor durability of the nourishment. To improve durability on future projects: imported grain size should be at least 1.5-2.0 times the native sand; unit sand volume should be 400-500 m³/m; and supporting measures should be utilized as appropriate.