Optimisation of water quality in complex man-made canal systems - Saadiyat Island, Abu Dhabi
Type:
Presented during:
CEDA Dredging Days 2012 - Virtue, Venture and Vision in the Coastal Zone
Authors:
Bundgaard K, Jensen A and Brøker I - DHI, Denmark
Abstract: In the recent years extensive reclamation and development of land areas has been carried out to create space for numerous prestigious resorts and artificial islands in the Middle East. In many cases these land developments are artistic masterpieces consisting of a mosaic of artificial lagoons, islands and beach areas. Examples of such geometrically complex systems are "The Palms and The World" in Dubai, "Pearl of the Gulf" in Qatar and Saadiyat Island in Abu Dhabi, Manifa Oil Field in Saudi Arabia. The massive construction works associated with these projects have raised environmental concerns regarding both the impact on water quality and sedimentation and the impact of the land reclamations on the water quality. The environmental impact and optimum design are usually assessed through dedicated numerical modelling studies. Given the extreme geometrical complexity of layouts, requirements to grid control and resolution are essential in order to quantify impacts on the current regime, wave climate, sediment transport and water quality.
"Saadiyat Island" is an approximately 10 km long and 5 km wide triangular island. The master plan (MP) for the Island includes artificial channels and reorganisation of an existing lagoon system thereby creating room for both mangrove areas, housing and recreational features. The flushing of water and the resulting water quality are governed by the flow through narrow straits on either side of the Island. Optimisation of the layout of the project to ensure good water quality in the artificial channels is of utmost importance for the success of the project.
Water quality is only one consideration. There are many other issues to be considered. Among these are habitat protection including benthic flora (coral, seagrass) from dredging/reclaim activities. Also mitigation measures to protect mega-fauna (dugongs, hawksbill turtles, whale sharks) during construction activities are a priority. But the present paper focuses on the water quality.
Detailed studies have been carried out to quantify flushing capacity and water quality for different configurations. The present paper illustrates the study methodology used in the flushing studies.
Keywords: Artificial lagoons, water quality, flushing, numerical modelling