ABU DHABI, 3 December 2005 — The skyrocketing costs of desalination plants, long used as the source of most fresh water, is leading governments in the Gulf region to look at a possible, cheaper source — the wastewater from sewage plants.

Ahmed Al-Sabban, deputy minister in the Saudi Ministry of Islamic Affairs, requested and received a pair of rulings from the Kingdom’s religious authorities that allow mosques to recycle water and use it for ablutions, the ritual washing that requires a high level of cleanliness.

“Is it dirty? Yes. But if it’s properly treated, it is valuable,” said Fady Juez, managing director of Metito, a Dubai-based company that designs water and sewage treatment plants.

Al-Sabban and Juez were among the experts from some of the world’s driest countries who gathered for a two-day conference in the United Arab Emirates (UAE) capital Abu Dhabi to seek ways to reuse the contaminated water that flows through their sewers.

“Right now only 2 percent of our water is recycled. That is very bad,” Al-Sabban told the conference. Since the ruling, Al-Sabban said a pair of Jeddah mosques have installed systems that recycle water after it is used for ablutions into the toilet system and then to irrigate the grounds.

Construction booms and government policies of providing free city water have pushed per capita consumption to the highest levels in the world: Water is lavished on golf courses, gardens and fountains, even as groundwater in overtaxed aquifers grows salty and unusable.

All Middle Eastern countries except Iraq and Syria face severe water shortages in coming decades, according to presentations given at the conference.

“We are the driest part of the world,” Juez said. “And we are multiplying like mad.” To compensate, Gulf countries have traditionally turned to desalination, which provides some 60 percent of the region’s needs. But such treatment plants are expensive and consume much energy.

Supporters of using wastewater say it can be rendered so pure that it can be drunk — or even used for ablutions.

Most wastewater here gets cursory treatment before being dumped into the sea or poured into the desert. Only about 1 percent is recycled for farming and landscaping, mainly in the UAE, Qatar, Oman and Kuwait.

Even if people balk at drinking or washing in treated sewage, participants said recycled wastewater could be quickly redirected toward irrigation and air-conditioning, or at least re-injected into aquifers to improve groundwater. Spend another 10 percent on a treatment plant and wastewater can be made suitable for irrigation, Juez said. For 20 percent more, you can drink it.

Singapore recently opened a treatment plant that uses ultra-fine membranes to convert city sewage into drinking water. The plant has become a popular tourist site.

Wastewater in Jordan is already filtered and recycled through the country’s drinking water reservoir. Kuwait’s huge new Sulaibiyah treatment is the world’s largest reverse osmosis plant, which filters sewage to standards higher than those governing drinking water in the United States. But that water is currently only used for irrigation, said George Labib, general manager of the country’s utilities authority.

Saudi Arabia is in the midst of implementing a $5 million project for water reuse and plans to spend another $50 billion on water over the next 25 years, said Water Ministry official Abdul Aziz Al-Jaber.

With 5 percent of global population, the Middle East has just 1 percent of the world’s accessible fresh water. But past efforts to convince people in the region not to waste water were frustrated by governments’ insistence on giving away the precious commodity, or selling it so cheaply that customers have no idea of its value.

“At least let them know how much it costs,” Juez said. “Send them a bill. Tell them ‘You used $150 of water this month,’ even if you don’t charge them.”