Wadi Dayqah water project to go ahead this year. An ambitious plan to harness the prodigious water capacity of the Wadi Dayqah reservoir in Muscat Governorate is back on track, with the state-owned Oman Power and Water Procurement Company (OPWP) set to launch an international competitive tender for this unique project. Envisaged is an Independent Water Project (IWP) of a capacity ranging from 90,000 to 125,000 cubic metres /day (equivalent to 20 â 27.5 million imperial gallons per day MIGD) that will tap the Wadi Dayqah reservoirâ the largest surface water resource in the Sultanate â to supply potable and irrigational water to parts of the capital area. (LINK). HIWI042018-07-03T02:17:58+02:00