By Richard Armstrong
This article was originally published by Pile Buck magazine.
The Panama Canal was first opened in 1914 as a bridge between the Atlantic and Pacific oceans. By allowing ships to skip the long, treacherous trip rounding Cape Horn, it cut shipping times down exponentially. But a century later, much has changed in both shipping and canal construction. As it was originally built, the canal isn’t big enough to take many of today’s vessels. To stay viable amid tight competition from quicker and cheaper alternative routes, the canal has been undergoing a major upgrade since 2007. The Panama Canal Expansion project will take eight years and cost over $5 billion before it is completed in 2015. As of April 2014, the project is 79 per cent complete, though due to delays there are concerns it won’t be finished until 2016.
The project aims to improve the canal in a number of ways. The navigation channels will be dredged on both the Atlantic and Pacific sides, as will the channels in Culebra Cut and Gatun Lake. This will enable the canal to accommodate vessels with deeper drafts than it can presently take. New, larger Post-Panamax locks will be built on both entrances to the canal. These are the so-called “Third Set of Locks.” A completely new channel will be excavated on the Pacific side, north of the Third Set of Locks, which will connect the new locks to Culebra Cut and Gatun Lake. And finally, the canal’s water supply and draft dependability is going to be increased.
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For the expansion of the navigation channels, the Belgian company Jan de Nul n.v. completed the dredging of the nearly 14-kilometre area on the Atlantic side in April 2013, after beginning the process in September 2009. Using several dredges simultaneously (including the hopper dredge Fillipo Bruneleschi and two cutter-suction dredges), the existing entrance was widened from 198 metres to 225 metres. In the process, nearly 18 million cubic metres of material was dredged and excavated.
On the opposite side of the canal, another Belgian company, Dredging International, worked from 2008 to 2012 to widen the navigation channel on the Pacific side to a minimum 225 metres. A number of dredges, among them the Vlaanderen XIX, Lange Wapper and D’Artagnan, removed 8.6 million cubic metres of material.
Pacific Access Channel
A new Pacific Access Channel is one of the big new additions to the Panama Canal. Once finished, this 6.1-kilometre channel will link the Third Set of Locks to Culebra Cut. But before work on the channel could get underway, a cofferdam was needed to separate the Miraflores Lake from the construction area. In a joint venture, Richard Goettle, Inc. and Ingeniería Continental, S.A. (ICONSA) of Panama were made subcontractor for the construction of the cofferdam needed for construction and excavation of the Borinquen Dam. The resulting cofferdam consists of 58 circular cells and their respective connecting arcs. For these fabricated connectors, L. B. Foster provided important technical consulting regarding their strength requirements. Ultimately, PilePro® SWC Weld-On and WOM connectors were used.
For the pile driving equipment, Goettle was supplied by Hammer and Steel with a 4,400-inch lb vibratory hammer, which drove the PS-31 sheets to a subsurface hard layer. When they got deeper, they switched to using a 5 Dawson HPH 1800 double acting hydraulic impact hammers. According to Hammer and Steel’s website, this was then “fitted with specific flat sheet inserts to accommodate the centering of the hammers over the interlocks, and specially designed spreader plates that afforded maximum coverage over the sheets and would best accommodate Goettle’s requirements. Stiff clays and dense granular material are ideal driving conditions for the Dawson impact hammers, especially where vibratory hammers meet significant resistance.”
The subcontractors only had 37 weeks to complete the cofferdam by the project’s required deadline. The joint venture employed around 120 workers, working 18 hours per day, seven days a week in two shifts. Despite challenges from Panama’s violent weather in its rainy season, the multiple crews were able to cut and install the sheet pile needed.
The dredging of Gatun Lake and Culebra Cut was also a major endeavor. In order to deepen and widen the navigation channel for the lake, 30 million cubic metres of material had to be removed. Explosives were placed in holes that had been drilled in the lake bottom. This was completed by Jan de Nul n.v. and Dredging International, using mostly the Canal Dredging Division’s personnel and equipment and with the aid of the Boskalis-owned dredge Cornelius. They completed their work by the end of 2012, but there is still dredging to be completed in Gamboa, Mamey and Juan Grande. So far 11.7 million cubic metres of material has been removed with the hydraulic dredge Mindi, the mechanical dredge Rialto Milhouse Christensen (RMC) and others. In addition to improving the navigation channels, work has also been done to improve the canal’s water supply. The maximum operating level of the lake has been raised from 26.7 to 27.1 metres, which means increasing the water storage capacity by nearly 200 million cubic metres. To fill this larger capacity, all 14 existing spillway gates were opened, along with two new ones.
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The Third Set of Locks
The biggest component of the Expansion Project is the design and construction of the Third Set of Locks. The consortium Grupo Unidos por El Canal – made up of Spain’s Sacyr Vallehermoso, Italy’s Imprgilo SpA, Panama’s Constructora Urbana, and Jan de Nul n.v – won the $3.2-billion contract in 2009. Two sets of locks will be built on both sides of the canal. Work on design and construction was done around the world, including Cimoloi S.p.A making the 16 gates and Hyundai Samho Heavy Industries manufacturing the bulkheads, valves and trash racks in South Korea. By the time the project is completed, the pair of new locks will each have three chambers, nine water-saving basins, a lateral filling and emptying system and eight rolling gates per lock as a redundant system.
The new locks will be more efficient and easier to service than the current ones. Their water-saving basins will require seven per cent less water than the current system, and will reuse 60 per cent of the water needed for each transit. Whereas the current filling and emptying system of the locks works through a series of ports on the chamber floor, the Third Set of Locks will use a lateral system with ports on the chamber walls. This means that filling each chamber will take only 10 minutes when the water-saving basins aren’t being used, and 17 when they are.
Gates
The first four rolling gates arrived on the Atlantic side in August 2013. Fabricated by Cimoli SpA, the gates are 57.6 metres long, 30.18 metres tall and weigh over 3,000 tons (once installed, they will be able to move at just 15 per cent of their actual weight thanks to their buoyancy chambers). They are going to be unloaded and installed (in the dry) by specialized self-propelled modular transports. The construction, transportation and installation of the new gate system will cost over half a billion dollars in total.
All told, six different types of gate are being made, each varying in size and functionality, depending on its location. To make up for the significant tidal variance at the Pacific entrance, the largest and strongest gate will be installed there. After looking at gate designs from all over the world, the rolling gates were chosen after designers liked the size and ease of use of the ones installed at the Berendrecht and Zandvliet locks in Antwerp. The gates will be installed in concrete recesses on one side of the chamber, and move along a track to the other side, perpendicularly to the central axis of the lock. This is a change from the current miter gates, which consist of two leafs, one on each side, and turn on an axis to open and close.
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Project challenges
The expansion project has needed a massive amount of concrete. So far, 3.5 million cubic metres out of an expected 4.3 million have been produced. This has required contractors to install industrial parks onsite to produce aggregates and prepare the concrete mixes.
Making the best use of the area’s natural resources, basalt extracted from the Pacific side has been crushed for use as aggregate and sand for concrete. But despite this, concrete has been the source of the biggest problems for the project. According to a July Newsweek article, cost overruns of up to 50 per cent on cement have led to problems between canal officials and the contractors. At the end of 2013, the consortium threatened to suspend the work on the locks if its existing claims for $1.6 billion were not met. After three months of tense negotiation, a deal was reached between the various parties to resolve the issue and continue work to complete the project.
The project has encountered other problems along the way. Because of the scale of the expansion, environmental concerns have been an issue. Since construction started in 2007, the project has had to follow strict environmental standards, including reforestation projects and the rescue and relocation of animals in the areas of construction. Long-dead animals have also been a concern; according to a story by AFP, thousands of fossils have been found on the site, including dinosaurs and teeth from a giant shark. Many valuable cultural artifacts have also been discovered, which have been recovered and catalogued through a partnership with the Smithsonian Tropical Research Institute. This includes artifacts from the early Spanish conquistadors, as well as items that predate the discovery of the continent by Europeans. More dangerous than shark’s teeth and arrowheads, crews have stumped on unexploded ammunition left behind by the United States military from its long presence in the Canal Zone. In the area where the Pacific Access Channel is being built, over 400 hectares had to be cleared of unexploded ammunition left over from firing and bombardment practice.
In addition to concrete, the project has required massive amounts of other materials: 279,000 tons of reinforcing steel; 47,200 tons of structural steel (for lock gates); and 20,000 tons of steel for the lock valves have been needed so far. For explosives, 1,500 tons of gelignite and 3,600 of ammonium nitrate was used. Blast furnaces have produced 436,000 tons of volcanic ash and slag.
Moving forward
Once completed, what will all this work mean for the future of the canal? Its capacity will be significantly improved. The expansion will cut down the wait time on using the canal, which at the moment can sometimes be as long as a week. According to Mercatrade, the width and length of the locks will increase by 160 per cent. The total annual tonnage traveling through the canal is expected to increase from 275 million tons now to 600 million tons once the project is completed.
The main purpose of the expansion project has been to accommodate today’s larger vessels. The canal will now allow ships up to 1,200 feet long and 160 feet wide to pass through, up from its current allowance of 965 feet and 106 feet, respectively. In terms of container load, the old limit was 4,800 containers per ship (or 4,400 TEU), but in the future this will be increased to 12,500 (or 14,000 TEU). Despite this massive increase in capacity, the Panama Canal still won’t be able to handle ships the size of Maersk’s Triple E Class, or even the new “smaller” megaships. But for now, the expansion project has greatly added to what a century ago was the largest engineering project in history.
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