In the March 2018 issue of Pumps & Systems, I presented an overview of the water infrastructure in Israel. Although Israel is a small country, the geographical and topographical climates are extremely diverse. For example, when it snows in the north in the Hermon Mountains, you can go for a swim in the south near Eilat or Aqaba, Jordan. Water is a major challenge in the Middle East, and Israel is no exception. Desalination plants are now growing in capacity and number, since there is no lack of salt water. Plans for major projects are in the works, including a joint venture between Israel, Jordan, Syria and Palestinian Authority for a major canal connecting the Dead Sea with the Red Sea. An oil transfer from Saudi Arabia through Israel to Europe is also a part of studies, as described in several publications, including the ones referenced below. Due to rapid drops from hills to valleys, this requires significant head pressures and numerous boosting pumping stations.
New Project
The city of Beer Sheva is in the middle of Israel with a population of 250,000 and is growing rapidly. It is essentially an oasis in the desert, and most of its water supply comes from wells and also by water pumped from the coastal desalination plants along the Mediterranean coast. A recently designed 22-acre area lake is scheduled to “come online” shortly, and plans are underway to add a river to the project—an unusual addition to the desert landscape. A river in the desert is becoming a reality, with a big technical, technological and environment challenge.Geography Challenges
Although not an Amazon River by any stretch, this river will be unique and flow for approximately 3 kilometers (km), at a water speed around 0.1 meters per second (m/sec), with an average depth of 3 m and width of 50 m. The terrain challenge is that although the land is relatively flat between the coast to Beer Sheva, it begins to incline rapidly from Beer Sheva toward the Dead Sea. The average elevation difference from the western boundary of the river to the eastern is nearly 70 m. Therefore, it would be necessary to complete a major landscape reconstruction with earth-moving equipment to decrease the local slope in the proximity of the river to about a 2 m slope along the 3 km river length. Once achieved, the parameters for the pumps would become:- river flow = 0.1 m/sec x (50x2) = 10 m3/sec = 36,000 m3/hr ~ 150,000 gallons per minute (gpm) rounded
- head (the slope after excavation and terrain modification works) = 2 m ~ 6 feet
- 10 vertical turbine pumps (VTP), 15,000 gpm each, 25 hp motors, 200 revolutions per minute (rpm)
- total power and cost at 10 cents per kilowatt hour (kWh) = 15,000 x 6 / 3,960 x 0.90 = 250 hp = 200 kW, for a total of $150,000 yearly energy cost
- holding/emergency tank = river volume = 3,000 x 50 x 2 = 300,000 m3 = 80 million gallons