Free zone firm to use waste water

DUBAI // The company that runs several free zones, including Dubai Internet City, plans to build a plant to recycle waste water for irrigating its land. The Tecom facility, which is expected to begin operating next year, will process effluent from Dubai Municipality's sewage treatment plant in Al Aweer. Recycling waste water is much less energy-intensive than desalination, the means by which almost all of the country's drinking water is produced.

"We need to be 100 per cent sure the water quality will not represent a health hazard," said Ali bin Towaih, director of Tecom's sustainable energy and environment division and also of the Energy and Environment Park. The municipal treatment plant has been operating at twice its design capacity of 11,000 cubic metres of sewage per hour. A new plant at Jebel Ali is being built, but will not be ready until the autumn.

In the meantime, the safety of the outflow is raising concerns. One particular issue is the amount of ammonia, a natural by-product of human waste, which is responsible for the smell of the outflow. The water produced by the plant has ammonia content of 30.7 milligrams per litre, while the limit is 1.5mg to 2mg per litre. The effluent also contains high levels of E.coli, a diverse group of bacteria that live in the gastrointestinal tract of humans and warm-blooded animals. Many strains are harmless, but some can cause serious illness.

The municipality has said the water is safe for irrigation. But many private developers have been cautious, mixing the effluent with potable water. Mr bin Towaih said that technically, the effluent could be used in landscaping, but that its use within large artificial lakes in many of the free zone areas presents a challenge. Tecom relies mostly on potable water; its water bill reached Dh4 million (US$1.1m) per year, he said.

Tecom is looking for a private company to invest in, build and operate the new treatment facility. Payments will depend on water bill savings. The project is part of Tecom's effort to reduce its water use by 30 per cent. It used 626 billion litres last year. Mr bin Towaih made his comments during Water Days, a two-day seminar held in Dubai. The event, which concludes today, gathered engineers, consultants and planners, all of whom maintained that the current level of water use in the country - at around 550 litres per person per day - is among the highest in the world and is unsustainable in the long term.

At the seminar experts agreed that potable water should be used only for essential applications. Using lower-grade water for tasks such as toilet flushing, cooling or irrigation, could greatly ease the pressure on the UAE's water supply, as well as reducing its energy bill. Mario Seneviratne, the director of Dubai-based Green Technologies and a green building consultant, said water reuse should be incorporated into the design of buildings.

vtodorova@thenational.ae