CH2M Hill, a global full-service engineering, procurement, construction, and operations firm has delivered design, construction and commissioning services to the Sharjah Electricity and Water Authority for two seawater reverse osmosis (SWRO) desalination plants in the United Arab Emirates. A third desalination plant for the Authority is currently under construction by CH2M Hill and is expected to be online by mid-2009.

The Sharjah Electricity and Water Authority is responsible for providing reliable and affordable electricity and water to the Emirate of Sharjah. As water demands increase, the authority is turning to SWRO membrane desalination to diversify and augment the region’s potable water supplies.

The new desalination plants will serve a critical need in the existing distribution network. The plants will provide more than 60,000 cubic meters per day of high quality desalinated water to the people of Sharjah.

The environments and source waters of the three plant sites differ dramatically, each presenting design and engineering challenges. The Layyah SWRO desalination plant lies on the Arabian Gulf, about 15 km northeast of Dubai. The Khor Fakkan and Kalba SWRO desalination plants are located on the opposite side of the Oman Peninsula on the east coast of the UAE, facing the Arabian Sea.

The engineering challenges have been addressed with an array of advanced desalination technologies.The Layyah and Khor Fakkan sites use dual-stage media filters for treatment of the raw seawater prior to reaching the high-pressure SWRO system. The Layyah site incorporates a dissolved air floatation system before the media filters for enhanced removal of particulates, and better protection against accidental oil spills and seasonal algae blooms.

Instead of conventional media filters, the Kalba desalination plant will use high performance ultrafiltration membranes that are specifically designed for SWRO pretreatment applications. All three plants incorporate the highest efficiency energy-recovery devices available.