Seven man-made islands, surrounded by an extensive network of navigable waterways connected to the Dubai Creek via weirs and locks, covering an area of almost 6.5 km2, and catering for a mix of uses including residential and commercial units, public open spaces, parks and board walks. That is the vision of the Lagoons project in Dubai, located at the upper end of the Dubai Creek.
Water as the project´s dominant feature
It is project developer Sama ECH (SECH) who is behind the Lagoons. The main feature of the project is the so-called "Pearls" - seven large islands, surrounded by waterways, and SECH decided at an early stage of the construction works to flood parts of the Lagoons waterways to create a vision of the future site with water as a dominant feature.
An important part of the engineering services, provided by engineering company Parsons, was thus the design of marine structures, hydraulic and water quality improvement measures. And being already involved in the project´s marine works, COWI was consequently engaged by Parsons to provide advice on the water quality management.
Key areas of COWI's services
COWI´s services were undertaken between 2007 and 2008 and the key areas of involvement included:
- Developing options for filling and maintaining water levels in the canals during the construction period. The analysis included development of a water balance, assessment of available water sources and groundwater dewatering assessment
- Assessing methods for controlling an artificial liner placed in the canals to mitigate leakage from the flooded canals. A system of relief pumping wells were designed to reduce the risk of the liner floating due to rising groundwater or development of gas/air below the liner.
- Developing concept for ensuring a good water quality in the canals. Particular issues were related to the very high salinity and risk of algae growth. COWI undertook detailed water quality modelling to assess the development in salinity and algae levels in time under different management scenarios. COWI also developed a concept for water treatment of the 3 mill. m3 water using innovative environmentally friendly methods including use of biological measures and ultra sound to manage the water quality in a transition phase until a permanent water flushing system was constructed.
