Author(s): Oscar Santos Garcia; Alberto Ruiz Berbel; Luis Castillo Cano-Cortes; Javier Martel Vilagran

Linked Author(s): Luis Castillo Cano-Cortés

Keywords: Modular pumping; Extreme weather; Feeder

Abstract: Saudi Arabia is an extremely dry country: without permanent river currents and virtually no rainfall throughout the year, inland Saudi water supply has been traditionally based on oasis and, since the 1940s, on a number of vertical wells. Population increase during the second half of last century brought about a decrease of 150 m in ground water+ level. Any feasible permanent solution pointed to the use of sea water. Nowadays, all inland Saudi population uses desalinated water coming from the Persian Gulf and the Red Sea. The Water Transfer Projects that AYESA is currently supervising in KSA ─ design and site supervision – are similar: tank farms, pumping stations and feeder lines. NSPW and QFD project comprises seven water transfer systems spread all along the Red Sea Coast. These, together with a new desalination plant on each site will dramatically improve water supply and enable development for minor cities located nearby. KKMC project is in the north-east end of Saudi Arabia, and transfers water from Hafr al Batin station to King Khalid Military City 80 km to the west. Modular construction for Pump Stations. The number of pumps and size of impellers (and thus flow rates, water pressure and velocity) will vary heavily in the coming years. Current design is ready for that. Weather conditions: high temperature, extremely low humidity and sandstorms determine some design parameters and equipment. The main feeder is a steel pipe lined with cement mortar, which needs special humidity supply during construction. Station piping would not resist the great temperature variations – from 85°C under the sun to 20°C at night –, so a different lining and coating is used in aboveground station pipes; electric and electronic devices must withstand extreme temperatures; buildings must be overpressured to avoid sand intrusion. Any work inside pipes must follow thorough safety checks of temperature, available oxygen and presence of gases. Topography: inland Saudi Arabia is a plateau of some 500 km² without summits or low points, which means pipe slopes are quasi-horizontal. To guarantee air release from the pipe walls we apply a mechanic wiping device used in the petroleum industry, a scraper; it is a plastic piece hydraulically driven by water pressure itself, which scrubs the pipe walls and carries the bubbles to the vent stations. Scrapers need special launching and receiving devices, and a careful valves disposition. Control and monitoring: state-of-the-art systems are implemented for leak detection and location systems. The Operation Optimization System based on demand prediction and costs, and Process Automatic Control are supported by a fiber optic communication network. Reservoirs: Tanks are aboveground steel structures around 60.000 m3 with aluminium dome roofs, and a passive mixing system to guarantee the quality of water.

DOI: https://doi.org/10.3850/IAHR-39WC2521711920221226

Year: 2022