A New Case for Wastewater Reuse in Saudi Arabia: Bringing Energy into the Water Equation

Industrial and urban water reuse should be considered along with desalination as options for water supply in Saudi Arabia. Although the Saudi Ministry for Water and Electricity (MoWE) has estimated that an investment of $53 billion will be required for water desalination projects over the next 15 years [1], the evolving necessity to conserve fossil resources and mitigate GHG emissions requires Saudi policy makers to weigh in much more heavily the energy and environmental costs of desalination. Increasing water tariffs for groundwater and desalinated water to more adequately represent the costs of water supply could encourage conservation, but also reuse, which may be more appropriate for many inland and high-altitude cities. The Saudi government should expand its support for water conservation and reuse within industry through financial incentives or through the implementation of cleaner production standards that encourage energy and water conservation and reuse. The case studies discussed in this work suggest that the implementation of water conservation, reuse and recovery measures in the natural gas [2] and crude oil [3] sectors alone have the potential to conserve up to 222 million m3 of water annually [2-4], or 29% of the total industrial water demand in 2009 [5]. In the municipal sector, increasing secondary wastewater treatment and reuse resulted in substantial cost and energy savings for six inland cities, while an estimated 26% of urban water needs could be met by treated wastewater. Therefore, industrial and domestic water reuse have the potential to appreciably reduce water withdrawals, conserve non-renewable aquifer water, and reduce reliance on desalination, which is primarily driven by non-renewable natural gas. Anticipated investments in desalination projects could also be deferred by prioritizing investment in sewage and water distribution networks that would ensure more effective water reclamation and reuse while simultaneously conserving non-renewable groundwater and natural gas resources and preventing the lock-in of potentially unnecessary desalination infrastructure that is likely to become more efficient in future.