FROM a trickle in an ornamental garden to the mighty plume that hisses high above Jeddah’s Al-Hamra Corniche, the fascination with water joyously bursting upwards, losing momentum, describing a lazy parabola of nebulous spray downwards and then recombining into liquid is perhaps a metaphor for the cycle of our existence. We come; we are temporarily magnificent; we are gone and the cycle continues.
That simple graceful jet of water — the water which constitutes 80 percent of the bodies that stand fascinated by the fountain — is the final glorious result of a very complex piece of engineering. In the manner of a swan, the fountain is all grace and poetry above the water, but working furiously underneath.
The Jeddah fountain which dominates the city’s skyline today is the second one built as a landmark for the city; both within the official Salam Palace perimeter. The first, built between 1980 and 1983, was very much in the style of the freshwater fountain in Lake Geneva which reaches 140 meters (460 ft) and lofts about seven tons of water into the air at any one moment at a nozzle speed of around 200 kph (124 mph).
Constructed to complement the Salam Palace island, the plume of the first fountain reached 120 meters. “The height,” said George Antonopoulos, Chief Operations Officer for SETE Technical Services (Latsis Group) which built the fountains, “was not impressive enough in comparison to the surroundings. The palace was huge and Jeddah is a huge city and expanding. A height of 120 meters was good but the scale was just not impressive enough.” Thus, the decision was made to build a fountain of singular majesty, one that would reach well over 300 meters.
“Of all our achievements in the Kingdom in the past 30 years,” SETE Technical Services Chairman Richard Bacos said, “the Jeddah Fountain is certainly the most visible and it makes us feel very proud every day of every month of every year.”
A fountain on such a grand scale presented unique challenges. Most fountains operate using fresh water; the Jeddah fountain uses sea water, and sea water’s abrasive qualities - salt content and suspended particles of sand, for example - presented unique problems. Corrosion, a particular threat with salt water, had to be minimized as frequent stripping and de-scaling and replacement of pipes would push maintenance costs steadily upwards.
The enormous pumps, power supply and pipe-work had to be positioned as near the jet as possible in order to counter the resistance built up by the flow of water through the lines to the jet. Yet, at the same time, the pipes must not be visible. The theoretical solution was simple; put them under water. Easy to say but difficult indeed to do.
The causeway carrying the pipes to the jet and the island that it is mounted on were retained. The rest of the support structure was built specifically for the new fountain. The pump room and electrical sub-station buildings were built in Rabigh where SETE was constructing an oil refinery.
“The buildings — pump-house and electrical substation — were constructed on a 90 meter-long submersible barge,” said Antonopoulos. “Seven thousand tons of concrete were used just to construct the pump house which is the height of a five story building.”
The completed structures were towed to Jeddah where the sea-bed had been leveled, ready to receive them. The barge was submerged so that the buildings, which were just buoyant, could be floated off and maneuvered into position, sunk and fixed in their final positions. Access corridors were built and once pumped dry, the buildings were fitted out. “All the machinery and logistics are 20 to 30 meters under water,” said Antonopoulos, “in order to blend with the surroundings.”
The main pump house accommodates three huge multistage centrifugal pumps and 18 auxiliary pumps for cooling, lubrication of the bearings of the main pumps and drainage.
“After the design stage, it took two or three years to ‘settle’ the operation,” said Antonopoulos. “There was no precedent we could use for building something like that. Everything started from scratch and in the first years, we were obtaining information as we proceeded which we developed and applied to certain aspects of the design.”
Each 3.5 MW pump delivers 625 liters per second; two of the three pumps power the water jet at the same time and deliver 1,250 liters per second. The third is available as backup. The pumps were made in Switzerland by Sulzer and the builders come yearly to check and service them. After nearly twenty years, the blue painted pumps are in immaculate condition, mounted in a pump room that is kept clinically clean.
The intakes for the pumps are in a specially-built pit that is pumped dry and treated yearly with anti-fouling paint which prevents the growth of marine life. The water passes through a series of screens and is clean when it reaches the pumps. It is also as free as possible of detritus in order to minimize pump and system wear. Delivered to the pumps in an 800 mm stainless steel pipe, the seawater exits at high velocity, through stainless steel pipes of steadily decreasing diameters, towards the nozzles.
“The high pressure output line is all stainless steel piping and is of unique design in terms of morphology,” said Antonopoulos. “The isometrics of the pipes were devised to avoid erosion from unusually high speeds of water. The velocity of the fluid is a major parameter in hydraulic design. You need special metallurgy to sustain these velocities and pressures, special stainless steels and piping,” he noted.
The project continually presented new challenges and SETE produced new and innovative answers. “It was two years of constant development on a learning curve the whole way,” commented Antonopoulos. “The fountain has been operating now for twenty years with planned maintenance; so far, no major problems.”
The job of building this unique fountain held one of the most intriguing challenges right to the end of the line.
On the 350-meter journey from the pumps to the jet, the diameter of the pipes steadily decreases from 800 mm to 126 mm in order to increase the water velocity to a maximum and so achieve the height required.
“Because there was no precedent for seawater mega-fountains, we found tremendous wear on the nozzles.” Antonopoulos explained. The wear is caused by the sheer force of the water, sea water salt burden and micro abrasives in suspension. “It is like hydro-blasting a piece of steel.”
The water leaves the 126mm nozzles at 42 bar (609.16 pounds per square inch) and at the incredible speed of 375 kph. The plume of water, when it hangs in the air for 15 seconds or so, weighs in excess of 18 tons (18,750 kg).
There was industrial experience of seawater fountains, but not at the water velocity, pressure and height specifications of the Jeddah fountain. Every month, the nozzles had to be replaced. SETE engineering set to work and developed a special alloy which was given to steel mills for casting. The unique alloy, S-JFN, a SETE proprietary alloy, is tough enough to allow the nozzles to last for years. “This was one of the results of collecting data and information and improving over the settling period,” said Antonopoulos. “We now have a very specialized body of knowledge on high pressure seawater.”
Even the lighting of the enormous plume presented challenges. Five hundred high intensity spot lights mounted on five custom-built islands illuminate the jet. The technology of overcoming corrosion by sea water was well known. What had to be overcome — and was — were the effects of battering by thousands of tons of water an hour falling from a height of several hundred feet.
A short time after the fountain began operating in 1985, heavy corrosion was encountered on the pipeline system. This was overcome by the installation of an impressed current cathodic protection system which protects the system by partial or full polarization of the object to be protected. The cathodic protection system was installed in late 1987.
The system was designed to protect the pipeline system at 17 points and has a total of 57 anodes and 29 reference electrodes which were installed and distributed on the pipeline system. Monitoring the conditions of the system was, and currently is, done by SETE electricians on a daily basis. Every two years, or after every major maintenance session of the pipeline, the manufacturer is invited to check and re-assess the system.
The elegance and simplicity of the plume, high above the pump room, belies the maintenance and care given to the machinery that produces it. The whole operation is computer controlled and has a comprehensive maintenance system — daily, weekly, bi-weekly, monthly, half-yearly and yearly. Ten technicians, including rotating specialists and electricians are dedicated full time to the fountain’s operation. In addition there is continuous support from the departments which are responsible for the operation and maintenance. The annual inspection takes around three weeks. “We follow this annual inspection routine very strictly,” said Costas Benissis, the Operations Maintenance Manager. “You cannot cut corners.” He went on to explain, “We shut the fountain down for only two reasons. One is for planned maintenance, usually once a year. So far,” he confirmed, “we have not had to shut down for any problem or unplanned event.”
The other reason for shutting it down is less obvious — if the prevailing wind from the north reverses direction and blows from the south. If that happens, the curtain of spray from the plume will carry into the gardens of the Salam Palace and kill the grass and plants. This finally lays to rest the myth that the fountain is fresh water. “Not so,” said Benissis. “The only fresh water in the entire self-contained fountain complex is for cooling the electric motors of the main pumps and for the air-conditioning in the pump-house.”
It is a fitting tribute to the modesty of the designers and engineers who created the fountain that their focus on overcoming the challenges and their insistence on “getting it right” has been so strong for twenty years that they overlooked what, to most people, would have been almost their first question about the fountain. Towering over Jeddah at — on a calm day — a mighty 312 meters (1,023.62 feet), none of the designers or engineers knew when asked whether it was the tallest in the world but Antonopoulos and Benissis confirmed that it is the world’s tallest sea water fountain. The plume is taller than the Eiffel Tower which is 300.51 meters (986 feet high. +/- 15cm depending on temperature)
The fountain listed in Guinness World Records as the tallest in the world is: “The fountain at Fountain Hills, Arizona, USA, (which) has a column of water reaching 171.2 m (562 ft) high. The fountain is set in a 28-acre lake and spurts a column of water for 15 minutes every hour on the hour between 10 am and 9 pm.”
Admitting to a glow of local pride, I would suggest to our Colorado cousins that, in comparison with the Jeddah fountain which has been operating faultlessly for close on 20 years, you have a leak gentlemen, not a fountain.
So next time you look at the gauzy pink veil of water trailing in the evening breeze with a billion ruby droplets shimmering with the ruddy glow of the dying sun, and the muse beckons you to poetic thoughts about the eternal cycle of our fragile existence, just remember two things. You are looking at a modestly unclaimed world record. And engineers put it there.
