Every drop of water supplied to Dubai’s homes, offices and factories is produced through desalination.
After use, it is delivered to the emirate’s single sewage treatment plant at Al-Aweer which is operating this winter at about twice its original design capacity.
Delegates at MEED’s Wastewater & Water Reuse conference in Abu Dhabi, at the end of November, were told that Al-Aweer is processing up to 500,000 cubic metres of sewage a day.
Most treated effluent is used in irrigation, but 200,000 cubic metres is now being dumped daily in Dubai’s Creek.
Abu Dhabi, in contrast, has invested in one of the world’s most extensive treated sewage effluent irrigation systems, which is deploying every drop of the 500,000 cubic metres being produced by Abu Dhabi city’s Mafraq plant. This is exceptional.
Throughout the GCC most effluent, not all of it treated, is being thrown away.
This can no longer be sustained for several reasons.
More than 8 million people live in GCC towns and cities that almost totally depend on desalinated water originating in the waterway.
It takes up to 200 years for water in the Gulf to be replenished by flows through the Strait of Hormuz.
Thermal production involves taking seawater, heating it to above boiling point and using the condensed water.
The residue, warm brine concentrate, is then returned to the Gulf.
This helps explain why the average temperature of the Gulf is rising.
As MEED conference delegates were told, desalination plants designed in the 1980s assumed average intake temperatures of just over 30 degrees centigrade.
New ones assume a temperature of 40 degrees centrigrade. And the Gulf is also becoming increasingly saline.
Environmentalists say the impact of desalination is being compounded by increasing pollution along Iran’s coast.
And if Iraq resumes diverting water from the Shatt al-Arab for irrigation, the Gulf’s salinity, already 50 per cent higher than most seas and oceans, will increase further.
Throwing water away is like burning money. Purifying treated sewage effluent is cheaper than desalinating sea water.
In mid-2009, phase one of the new Jebel Ali sewage treatment plant opens.
It is planned to have daily capacity of 300,000 cubic metres and there is space on the site for more than 1 million cubic metres.
What will be done with the treated effluent? Supplying it to Dubai’s power and water stations in the same area might be the answer.
The output, since it will be sterile, could even be used for drinking purposes. This seems to make more sense than dumping it into the sea.
New solutions to the Gulf water challenge are being suggested by private investors taking stakes in the region’s water reuse industry.
They own 40 per cent of companies awarded concessions for Abu Dhabi city and Al-Ain earlier in 2008.
Seeking profit and facing higher borrowing costs, these companies are looking for ways of lifting revenues and cutting expenses.
Using treated effluent more productively looks like good business.
Most UAE private developers are also being obliged to invest in their own sewage treatment systems.
Some want to build grey water recycling systems.
This involves installing separate drainage for showers, hand basins and washing machines.
Since its impurities are lower, grey water is less costly to process.
Cutting edge real estate investors are also thinking about closed-cycle systems in which every drop of water, including condensation, is captured and reused.
New technology may make possible the full exploitation of residual solid waste in agriculture and landscaping, in energy production and even in building materials.
These are exciting times for the wastewater industry, the overlooked partner in the flourishing Gulf water production business.
But many questions remain unanswered.
Is the water reuse solution large centralised units using conventional technology that are served by huge pipe systems as Abu Dhabi plans? Or is it small ones using membranes that save on sewer costs, as is happening with increasing frequency in Dubai? How can risks be mitigated in privately-financed water reuse projects? Where is the private finance going to come from? And what is the right type of regulation?
A joined-up approach to water management, including conservation of groundwater and the Gulf, is on the agenda.
Abu Dhabi has announced it plans to carry out the region’s first comprehensive water reuse report.
As water rises up the region’s policy agenda, other initiatives are bound to follow.
This is a complex issue.
Here is a simple initial suggestion. People responsible for producing water in the GCC should speak more often with their counterparts dealing with it when it has been used.
Perhaps they should even be in the same organisation?