Abu Dhabi has achieved 100 per cent TSE reuse by using it to irrigate agricultural land, green spaces and golf courses
TSE=Treated sewage effluent. Source: MEED
Already the most water stressed region in the world, the Middle East and in particular the GCC’s water crisis is set to worsen. Water availability is expected to halve between now and 2030, when the GCC’s population is expected to rise to 52 million, from about 41 million today.
Over the past decade, the region has focused on creating new water supplies by building desalination plants. Despite the billions of dollars that have been spent turning seawater into drinking water, it will be a huge challenge for the desalination sector to meet current and predicted demand for water. It is estimated an increase of 90 per cent of total desalination capacity in the GCC would be required.
[With] a strategy of reuse, you … lower the overall cost of water, [and bridge the demand and supply gap]
Hu Fleming, Hatch Water
“Over the next five to 10 years, the combination of population growth and industrialisation means that on any projection just throwing additional desalination capacity won’t add up to sufficient water being available,” says Hu Fleming, global managing director of US-based consultant Hatch Water and representative of the International Private Water Association.
“Adding desalination capacity is also the most expensive way of meeting water demand. If you have a strategy of some reuse, you not only lower the overall cost of water, you get close to bridging the gap between demand and supply.”
Recycling water increasingly popular
For these reasons, most GCC governments are shifting away from desalination to recycling water, with most state-run wastewater companies hoping to attain 100 per cent treated sewage effluent (TSE) reuse within the next few years. The levels of reuse vary greatly across the GCC: Abu Dhabi is already there, while countries, such as Oman and Saudi Arabia, lag behind, with the latter reusing less than 20 per cent of its treated effluent.
|Middle East wastewater sector|
|Percentage of population covered by sewerage system||Percentage of TSE reused|
|TSE=Treated sewage effluent. Source: Frost & Sullivan; UN|
In places such as Abu Dhabi, 100 per cent reuse has been achieved by using TSE to irrigate agricultural land, public gardens and golf courses, instead of ejecting it into the sea.
As well as reducing desalinated water demand, it makes financial sense to use TSE for irrigation. TSE typically costs between $0.15-0.20 a cubic metre, compared with $1 a cubic metre cost of desalinated water.
An example of such savings is Kuwait’s Sulaibiya facility, the first wastewater project to be developed under a private concession in the region. Sulaibiya was commissioned in 2004 and comprises a tertiary wastewater treatment and an ultra-filtration and reverse osmosis plant, producing 425,000 cubic metres a day (cm/d) of TSE safe enough for consumption.
Treated wastewater produced at Sulaibiya is sold at KD0.18 ($0.66) a cubic metre, whereas the cost of producing a cubic metre of desalinated water is KD0.62 – a saving of $1.61 a cubic metre, or $213m a year.
|Recycled wastewater’s contribution to overall water withdrawal|
|Source: Frost & Sullivan|
The other area where TSE usage is on the rise is as a water supply for district cooling systems. It is this application that Saudi Arabia’s National Water Company (NWC) is using in its efforts to both increase the country’s TSE use and place a monetary value on the recycled water.
Saudi Arabia is ranked the third-largest per capita water consumer in the world, with daily consumption of 248.7 litres a person. As a result, the kingdom is also the largest producer of desalinated water – accounting for 17 per cent of global capacity. Now the country aims to become the GCC’s biggest TSE market, with a target of increasing reuse, from its current volume of 0.34 million cm/d to 1.9 million cm/d in 2020.
Treated sewage effluent supply contracts
As part of a wider plan to privatise the kingdom’s water sector, NWC in 2010 initiated a series of TSE supply contracts for companies and developments across the kingdom. NWC has signed 10 contracts or memorandums of understanding to sell TSE to industrial consumers, already worth about $60m a year. It is in talks with firms over a further seven contracts that could be worth $66.6m a year.
Most recently, in April NWC signed the agreement of prequalification, operation, maintenance, marketing and sale of the TSE and the transport for the reverse osmosis plant with Riyadh-based Mowah. Up to 50,000 cm/d could be transported and used for the industrial zones located south of Jeddah city. This followed the district cooling and irrigation agreement signed in 2010 worth $320m over 20 years with Knowledge Economic City in Medina.
NWC is studying its sale of TSE contracts to see whether the revenue could form the basis of a PPP model for financing future wastewater treatment plants.
However, with NWC pricing TSE at market levels, rather than at the subsidised rates that potable water is sold for in the kingdom, some question the likelihood of the scheme’s success.
“It is always going to be a struggle for TSE to compete commercially when they are selling desalinated water at a fraction of its cost,” says Ghassan Ejjeh, director and past president of the International Desalination Association. “If you are selling TSE at three or four times the cost of other water, then it creates a barrier. However, the pressure of availability may mean that TSE still makes progress.”
The price charged for water, which is currently set by the government at one of the lowest levels in the world for municipal customers, is the equivalent of less than $0.03 a cubic metre.
Removing subsidies from water tariffs
At the Saudi Water & Power Forum held in Jeddah in 2010, NWC chief executive officer Loay al-Musallam admitted the subsidy structure needed to be partially, if not fully, removed from water tariffs, to encourage customers to conserve water, but added that politically it was very difficult.
As well as the sheer pressure of availability, TSE reuse is growing in the region against a backdrop of global trends in the market. Acceptance of TSE reuse is growing worldwide, as a result of environmental lobbying. Perhaps, more importantly, the methods of treating water have become cheaper and more technically sophisticated.
The newest wastewater treatment plants in the region typically employ membrane bio reactor (MBR) technology, which offers many advantages over conventional activated sludge or trickling filter technologies.
“The old methods always left room for something to go wrong in the treatment process,” says Ejjeh. “With new technology, such as MBR and reverse osmosis, the chances of something going wrong have really reduced.”
A recent study by consultant Frost & Sullivan pegs the current size of the MBR market in the region at $100m-150m, with several large capacity plants being installed.
Muscat recently commissioned the Al-Ansab wastewater treatment plant in the Bausher region of Oman. The MBR plant has a capacity of 76,000 cm/d and treats sewage to low levels of suspended solids for use in irrigation and other industrial applications.
A 25,000 cm/d expansion of the plant is already planned and is due to be tendered this year as part of the $4bn Muscat wastewater project being developed by Haya Water.
Three treated-effluent reservoirs and distribution networks are included in the Muscat wastewater project. The total length of the treated effluent distribution network will be 308km.
Elsewhere, other projects in the pipeline using MBR include the Jebel Ali Free Zone Utility’s 108,000 cm/d plant and Jumeirah Golf Estates Sewage Treatment Plant of 220,000 cm/d in Dubai.
While Abu Dhabi already uses all of the TSE it produces for irrigation, Ejjeh says through the Federal Electricity and Water Authority a market for TSE is emerging in the northern emirates.
“The scarcity of water in the poorer northern emirates is such that a thriving market for TSE is emerging,” he says.
The combined stress put on water availability by increasing population and industrialisation in the region will mean TSE reuse will continue to grow throughout the region.
“It’s pretty clear that finally there is recognition that the greatest source of water in the region in terms of ease of economic access is waste water,” say Fleming.
But the critical questions are how fast, how far and at what cost will the TSE market grow?
Full potential for treated sewage effluent
For both Ejjeh and Fleming, there are several issues that still need to be addressed for TSE reuse to reach its full potential, namely encouraging the social acceptance of reusing wastewater; and concerns over the organisation of water authorities and the subsidising of water.
“The critical thought processes and masterplan of how to deal with water issues are missing,” says Fleming, saying that governments in the region need to identify not just how much reuse they want, but the different levels of treatment needed and different applications for it – so delivering the most cost-efficient solution.
“The complicating factor in the region is that the wastewater companies have been different to the water providers. So you have contracts only about managing waste, not looking at a potential source of water. The issue is political, not technical.”
Ejjeh praises Abu Dhabi for leading the way in bringing wastewater services into the Abu Dhabi Water and Electricity Authority, but adds that until the large water subsidies in countries such as Saudi Arabia are removed, growth of TSE as a water source at a commercial level is likely to remain restricted.
“In my ideal world, you have full cost recovery of everything, because only then do you reach the right conclusions as to what your priorities should be in water,” he says. “This is unlikely to happen in the Gulf states for the time being.”