Potable and Process Water Production and Distribution
Marafiq’s desalination plants produce potable water for Jubail and Yanbu industrial cities that meet not only the stringent standards of the Royal Commission, but also the World Health Organization’s Guidelines for Drinking Water Quality. This is ensured through continuous water sampling and laboratory testing. In addition, automatic sensors are used to monitor water quality.
High-quality process water is also produced for industrial customers in the two cities.
In Yanbu the installed desalination capacity in the central utility complex is 146,160 cubic meters per day. Water from the Red Sea is fed to nine multistage flash distillation (MSF) units. The units use heat recovered from the gas turbine power generators for the distillation process to produce steam which is then condensed into fresh water.
Yanbu also has two reverse osmosis (RO) plants. Some of the desalinated water is chlorinated and re-mineralized to produce potable water. The rest of the water, still chemically pure, is used for industrial processes. The water is stored in three potable water storage tanks and three process water tanks, each with a capacity of 40,000 cubic meters. Water is distributed throughout the city to households, industrial users, and other facilities through more than 510 kilometres of underground piping via several pumping stations.
The Early Days of Jubail Water
Jubail’s first and primary source of fresh water was a well under the sea just to the north of the town. It was called Ain Ghumisah. To fetch water from it, divers had to swim down to the head of the well and hold their leather bags over the bubbling spring to fill them.
To provide a more readily available water source to the town’s citizens, the late King Abdulaziz Al-Saud ordered to construction of Al-Tuwayyah Tower over the well with the same name. The tower was completed in 1930 and is still a historic landmark in Jubail. After Ain Ghumisah, Al-Tuwayyah was the main water source until the exploitation of the area’s 12 artesian wells. An artesian well is a well that is drilled through solid layers to reach water deep down where the internal pressure is so great that the water rises to the surface.
Ain Ghumisah rose from the depths again in 1980 when the new Ghumisah arrived in Jubail. The Royal Commission installed a floating, barge-mounted desalination plant, constructed in Japan and towed all the way from there, close to King Fahad Industrial Port. It was aptly named Ghumisah after the first underwater well. The plant was designed to produce 16,000 cubic meters of potable water per day through a multistage flush (MSF) distillation process, which was considered quite enough for the needs of Jubail at the time. It has been in full operation until very recently until the advent of the towering IWPP right next door, which produces 800,000 cubic meters per day.
Jubail has two MSF and three RO plants with a combined capacity of 84,000 cubic meters per day. The MSF plants use water from the Arabian Sea for desalination and potable water production, while the RO plants are fed from 12 artesian wells in the Jubail area.
The water is stored at two central bulk storage facilities with a total storage capacity of more than 1,6 million cubic metres. From there it is pumped to 32 local storage tanks and pumping stations at strategic locations in the industrial, commercial and residential areas of Jubail Industrial City.
Before the completion of Jubail IWPP, which supplies Marafiq with 300,000 cubic metres of potable water per day, the bulk of Jubail Industrial City’s water supply – 136,000 cubic meters per day – came from the Saline Water Conversion Corporation. Marafiq’s desalination plants provided supplementary quantities to meet the city’s daily requirement. The roles are now reversed, with the IWPP providing 500,000 cubic meters per day to SWCC for distribution to other parts of the Eastern Province.