REPORT ON THE HYDRAULIC ANALYSIS OF THE PUMP STATIONS AND PIPELINES FOR THE DOMESTIC WATER PROJECT - NORTH JORDAN

Study, prepared by a contractor under Project 2780181, is based on site visits, interviews with project personnel, and a review of engineering reports. Current designs for stations and discharge lines are based on conservative engineering practice. To coordinate flow among the six stations will require numerous intermediate facilities and personnel. Alternatives (cf. the author"s book, "Waterhammer Analysis") to hydro-pneumatic (HP) chambers for surge control at stations 1-4 do exist. HP tanks at stations 1-4 should be protected with enclosures and emergency probe levels installed for surge protection. The 16 pumps and motors at these stations must be specifically designed; spare parts cannot, therefore, be replaced within 2 days as stated earlier. Pump discharge check values at stations 1-4 will require oil dashpots or snubbers to prevent damage from check value disc slam during power failures. The 1.2 m ductile iron pipe should be used at the intake pump station discharge line and at the upper sections of the discharge line of station 5. The following alternatives to current plans are offered: (1) To reduce the number of personnel and intermediate facilities and for greater dependability, consider combining stations 1-2 and 3-4, installing a spare pump in each. (2) Other surge control methods should be studied, e.g., the use of two speed discharge value closures (without pump check valves or HP chambers) to control pressure surges and to reverse pump rotation during power failures. (3) The initial power requirement at shutoff head for multi-stage pumps with submerged intakes and closed discharge values is half of what is needed for full flow pumping; this favorable characteristic can be used to optimize the number and size of pumps at each pumping plant. (4) Pump submergence for multi-stage pumps is based on the head delivered at the first stage. With a double suction intake for the initial and 4-5 pump stages, no additional pump submergence with the higher head pumps should be required.