Study Results

In 2008, the Jebel Ali WWTP produced 137 MCM of recycled water through its waste treatment processes. Out of this, 91 MCM were used for irrigation while the remainder was discharged to the environment. In 2019, capacity was increased to 383 MCMwith 232 MCM used to irrigate 6,250 ha of land. Currently, the WWTPs in Dubai (Jebel Ali Phase 1 and 2 and Warsan) provide around 700,000 m3 /day of treated effluent, which is used as irrigation around the city for landscaped areas, urban greening projects and afforested areas. This water reuse has played a major role in transforming what was an arid region into a beautiful, green, thriving tourist haven for USD 100,000/day. If the same quantity of fresh water has been used for irrigation, it would have cost more than USD 2 million/day of public money. This amounts to a saving of USD 1.9 million/day, which over a year adds up to USD 690 million. Recently a plan was put forward to recharge the groundwater aquifer system with recycled water from Jebel Ali WWTP. The Dubai Municipality carried out a feasibility study in 2020 and is currently starting a pilot project to assess its technical and economic viability. Based on pilot project results, surplus irrigation water could be used to replenish the aquifer increasing the groundwater reserve and the quality of the groundwater quality. While water reuse for irrigation purposes relieves demand on costly desalinated water resources and brackish saline groundwater resources, there are concerns about impacts on human health as well as groundwater and soil pollution and salinity due to the presence of organic pollutants and heavy metals in the recycled water (Dawoud 2017). Collecting, treating and reusing wastewater for irrigation in landscaping, afforested areas and landscaping can bring socioeconomic, health and environmental impacts such as: Increasing green landscaped areas where there is a lack of access to other alternative water resources. Minimizing the use of desalinated water for irrigation, which reduces energy consumption and associated carbon emissions from the desalination process and reduces costs – desalinated water costs USD 3.2 (AED 10.2)/m3 compared to USD 0.51 (AED 1.9)/m3 . Reducing negative health and environmental impacts by reducing wastewater discharge. Reusing the treated wastewater from Jebel Ali WWTP will help to improve and enhance the deteriorated groundwater quality and reserves for future uses. The wastewater treatment plants are also designed in line with the Government of Dubai’s Energy Conservation and Sustainability Strategy. Where possible they use rationalized energy-consuming processes and components such as gravity rather than pumping to convey water, adopting bio trickling filters to remove ammonia instead of aeration and using biological scrubbers to remove odors. Technological innovations such as variable speed drives for selected pumping needs and advanced process automation systems also help reduce energy use. Other benefits to the environment include contributions to the sanitation of Dubai Saltwater Creek and thereby to the Public Health and Environment of the Dubai City at large. Efficient management of the Jebel Ali WWTP together with the sustainable management of its produced wastewater is anticipated to become a cornerstone in terms of achieving progress toward Dubai’s sustainability goals. The Dubai experience is scalable in the region and elsewhere in terms of: Technology and Service Solutions: The wastewater system in Dubai has long sewage network lines of different diameters which are 3,000 km long, with 56 sub-pumping stations, corresponding to 10 main pumping stations and two sewage treatment plants in Jebel Ali and Warsan. To control and manage this huge infrastructure and the assets it contains, the Dubai Municipality inaugurated a remote-control system at the Jebel Ali WWTP. This remote monitoring and control system means a comprehensive database can be maintained that enables supervisors to analyze data and submit reports and supports them to make informed decisions. Data from the system also helps develop and plan maintenance programs. Reuse and Achieving Zero Discharge to Environment: The Dubai Municipality is the first in the region to reach zero discharge of wastewater to the environment. All produced waste is fully utilized for irrigation and future production increases will be used for groundwater aquifer recharge to enhance the groundwater quality and reserve.