BREAKWATER
Breakwater Crescent Palm Island Jumeirah
The breakwater crescent of Palm Jumeirah is about 11 km long and 200 m wide in cross section. It stands over 13 feet above low tide sea level and sits in 34 feet of water at the deepest point. The crest of the breakwater is 3-4m above mean sea level. The seaward slope is one in two. The composition of the breakwater consists of coarse sand, quarry run, and 5-6 tonnes of sand. The seaside breakwater is protected by rubble mound armor. The lowest layer of the breakwater is filled with sand. Rocks weighing one ton were placed on top of the sand followed by two more layers of rocks. In addition, there are two 328-foot openings on each side of the breakwater to enhance water circulation. According to the Case Study No.1 Design of Palm Island, water renewal time is approximately 13 days, slightly different than the estimated average renewal times in another article, which stated 10.1 days. The fact that the latter estimate was derived during the construction period can explain the different results. Water circulation around the fronds and open sea is critical for marine life, supply of oxygen and the removal of pollution. Furthermore, there is a retaining wall between the Crescent and fronds. Another layer of rock is placed in front of the wall to reduce overtopping quantity. (Stive)