Water Infrastructure in Oman
Dams, Irrigation Systems, Wastewater Treatment Plants, Large Well Fields
Among the major water infrastructure is a large number of desalination plants, including nine plants in operation that produce more than 100,000 m3/d of fresh water and three others that are due to start operating in the next two years; some of the largest membrane bioreactor (MBR) and sequencing batch reactor (SBR) plants to treat wastewater; Wadi Dayqah dam, which has a storage capacity of 100 MCM; recharge dams to replenish groundwater; and water supply and sewer networks in the cities.
Desalination operations are integral pieces of Oman’s utility infrastructure, and they provide millions of Omanis with potable water. Water demand in the Main Interconnected System (MIS) is expected to grow between 5% and 7% annually for the next seven years, surging from 281 MCM in 2015 to between 390 MCM and 440 MCM in 2022.
Traditional Water Collection and Distribution Systems
The traditional aflaj system is widely used in rural areas, mainly for supplying irrigation water. Annually, aflaj supply around 486 MCM of water.
Aflaj (singular: falaj) are channel systems that access groundwater by gravity flow from underground galleries or surface springs on neighbouring mountain slopes. There are more than 3,000 aflaj in Oman, with an average water supply of 552 MCM/yr and losses of 128 MCM/yr due to leakage at the main canals. There are three types of aflaj systems in Oman: ainy, daudi and ghaily, of which ainy and daudi utilize groundwater. Ghaily aflaj intercept the surface water from wadi flow and direct it towards the desired areas. These aflaj are dependent on surface water and they are active only in wet periods. Ainy aflaj intercept the discharge of natural springs and mainly originate from bedding planes, faults and fractures of the carbonate rocks or ophiolites. Daudi aflaj intercept the main groundwater flow by means of channels drilled horizontally along the slope of topographic highs to reach the water table.
 OPWP, 2016. OPWP’s 7-Year Statement (2016-2022). Available at www.omanpwp.com/PDF/7YS%202016-2022%20Final%20.pdf.
 Available at: http://www.unep.or.jp/ietc/publications/techpublications/techpub-8f/C/Oman1.asp. Accessed on: 4/11/2018.