In late August, traffic jams at the Atlantic and Pacific entrances to the Panama Canal impeded a healthy chunk of the world's maritime commerce. Each day, on average, more than 40 massive ships, many of them three times as long as a football field and piled high with cargo, rode at anchor in impromptu fleets that stretched across the horizon. On the Atlantic side, most of the ships carried grain from the American heartland, bound for markets in Asia; the vessels on the Pacific side from the Far East were jammed with cars and electronics destined for the U.S. East Coast. Some ships with daily operational costs of $40,000 waited as long as a week for passage.
Ninety-three years after it first opened for business, the Panama Canal is finally maxed out. Designed before the Titanic was even on drawing boards and while the Wright brothers were still learning to fly, the canal today handles more traffic than its builders could have ever imagined. About 14,000 vessels carrying 5 percent of the world's ocean cargo -- 280 million tons -- pass through the waterway each year. Despite running the canal around the clock -- at close to 90 percent of its theoretical maximum capacity -- canal officials are struggling to keep up.
The December 1913 issue of PM.
But with global trade booming, major shipping companies are willing to pay dearly for the 50-mile transit across the Isthmus of Panama. During periods when traffic backs up, canal officials sometimes institute an auction to determine which ships get through first. On Aug. 26, BP Shipping bid $220,300, a record for oil tankers, to jump to the head of the line. When combined with the regular transit fee, the passage cost BP $400,000. The auction price was not an anomaly: It was the fourth oil-tanker record that week.
The August traffic jam highlighted both how integral the canal remains to global shipping, and how vulnerable that shipping is to delays. The backup began when crews had to shut down one of two lanes in the Gatun Locks for routine maintenance. A massive breakdown could be devastating. Much like an aging bridge or highway, the Panama Canal has become a transportation paradox -- at once a vital artery and a worrisome bottleneck.
For years, major shipping companies built vessels designed to fit the canal's 110-ft.-wide lock chambers the way an ice cube fits in a tray. These so-called Panamax ships carry the bulk of the cargo that transits the canal. Increasingly, however, global shippers are building even bigger vessels, known as post-Panamax ships, that cannot fit through the current canal. (In North America, goods that bypass the canal typically cross the States or Canada by rail.) By 2011 those vessels will represent 37 percent of the world's container ships. To Panama Canal officials, the phrase post-Panamax has a grim ring: It suggests a time in the near future when the canal may become obsolete.
Egypt's Suez Canal already handles 20 percent more traffic than the Pan-ama Canal and generates more than twice as much revenue. And the lockless, sea-level shortcut between Europe and Asia can accommodate supertankers that dwarf the largest vessels transiting the Central American isthmus.
Panama can't afford to let the canal become a backwater. So in October 2006, the country's voters overwhelmingly approved a $5.25 billion plan to expand and modernize the canal. The project will include two new sets of single-lane, three-step locks -- one set at the Atlantic entrance and one at the Pacific; two new navigational channels to connect the new locks to existing channels; and deeper, wider versions of existing shipping lanes. In all, canal crews will dredge 130 million cubic meters of rock and soil, enough to fill the Empire State Building nearly 130 times. The new traffic lane will be large enough to accommodate post-Panamax ships and will double the canal's capacity.
VITAL CROSSROADS
Rush Hour: Transiting ships crowd Miraflores Locks and Miraflores Lake.
The grandest public building in Panama is not the president's residence or the National Assembly. It is the Panama Canal Administration Building, a stately, tile-roofed structure that sits atop a pyramid-shaped hill near the Pacific end of the canal. It was inaugurated in 1914 as the headquarters for America's canal officials. Since 1999, when control of the canal was transferred to Panama, the building has housed the Panama Canal Authority (in Spanish, ACP), a branch of the Panamanian government.
The edifice reflects the outsize importance of the canal to Panama. The waterway accounts for 14 percent of the tiny tropical nation's gross domestic product, and its full import is even greater. "I can't think of a country where you can point at one thing that has the significance that the canal has to Panama," says Richard Wainio, director of the Port of Tampa. Wainio grew up in Panama and worked at the canal, just as his father and grandfather did. "It is more than economics. It is more than just business. It dominates the hearts and minds of Panamanians."
Inside, ACP officials still work at the huge square desks that were built to allow chief engineer George W. Goethals and other early administrators to spread out enormous plans and blueprints. In a quiet office, ACP deputy administrator Manuel BenÃtez lays out the rationale for expansion. "The canal today is a clockwork operation," he says. "But the number of transiting ships is approaching the physical limit of the canal." BenÃtez notes that the idea of expanding the canal has been around almost since its inception. In 1939, the United States began excavations to enable the canal to accommodate a new generation of warships, but the start of World War II cut the project short.
The ACP reviewed dozens of options before deciding to complete the Depression-era U.S. work. "On the Atlantic side, all of the American excavations are usable," BenÃtez says. "On the Pacific side, we can use part of the excavations." The agency believes it can finish the project in seven or eight years with fewer than 7000 workers -- less than 10 percent of the number who toiled on the original American construction from 1904 to 1914.
The key to the project is its scale. The new reinforced-concrete lock chambers will be 1400 ft. long, 180 ft. wide and 60 ft. deep, with each lock complex measuring more than a mile and a half in length. "This will be by far the longest lift complex in the world," says Agustin Arias, ACP's director of engineering. "But most of the technology that we are recommending is in practice elsewhere."
Even in a tropical country receiving more than 100 in. of rainfall annually, the biggest challenge facing engineers is the need to save water -- an increasingly scarce resource in Panama. "The problem isn't rainfall," BenÃtez notes, "but storage." Man-made Gatun Lake is a 166-square-mile reservoir that is replenished during the country's seven-month rainy season. But the canal watershed supplies drinking water to 95 percent of the population around the waterway, and deforestation has affected the quality and quantity of the runoff.
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Transits Times Two
By 2015 new locks and channels will double capacity.
Map by Superfuture
More than half the $5.25 billion budgeted for the expansion of the Panama Canal -- $3.35 billion -- will be spent on new single-lane, three-step locks at the Atlantic and Pacific entrances, as well as on new channels. The new locks will not replace but augment the existing locks, and allow the canal to handle larger post-Panamax ships and tankers. To connect those locks to existing shipping lanes, nearly 5 miles of channels will be excavated. The current route through Gatun Lake will also be deepened by 5 ft. and widened, from today's 500 ft. minimum, to 920 ft. on straightaways and 1200 ft. in the turns. Gatun Lake will then be raised 1.5 ft., providing an extra 550 million gal. of water each day for the locks and alleviating concerns that canal expansion will tax water supplies. About 130 million tons will be excavated over the next seven or eight years, more than half the amount removed during 34 years of French and U.S. digging. Dry excavation could begin this year; work on the new locks could start in 2008 and on Gatun Lake in 2011. |
Tight fit: Panamax ships have a clearance of about 2 ft. on either side in the current canal locks. Electric-powered "mules" are used to position vessels. (Photo by Danny Lehman/Corbis)
The biggest tax on the water supply, though, is the canal itself. It requires, on average, more than 2 billion gal. per day to fill the locks for passing ships. An expansion plan that included bigger locks with a traditional design would have doubled water consumption. One way to address the problem -- build dams to create new reservoirs -- was a nonstarter. It would have meant relocating residents, even entire communities, which was politically unpalatable.
Then, in 1999, canal officials visited the Hohenwarthe Locks on the Elbe River in Germany and saw a solution: locks that recycled some of the water used in transits. "It was one of those 'Aha!' moments," says Raúl Brostella, an ACP port captain. "In effect, you are able to reuse water that would otherwise be flushed out to sea."
Three shallow basins adjacent to each chamber in the new locks will collectively capture 60 percent of the water from the locks as they are emptied. This water will be used to partially refill the locks when another ship comes through. As a result, although the new lock chambers will hold 65 percent more water than the originals, they will use 7 percent less water per transit. The canal authority also will raise the level of Gatun Lake, making an additional 550 million gal. of water available each day. BenÃtez sketches the plan on a notepad, explaining that, by doubling up smaller ships in the new lock chambers, officials can limit the use of the older, more wasteful, locks. But even if both sets of locks run full tilt, he says, "we will run out of capacity before we run out of water."
PUTTING MULES OUT TO PASTURE
The canal's current miter gates are based on a design found in the 15th century notebooks of Leonardo da Vinci: double-leaf doors hinged on chamber walls and sealed by water pressure. Each leaf is 65 ft. long, 7 ft. thick, and 47 to 82 ft. high; the most massive weighs 730 tons. For repairs and maintenance, they need to be removed and taken to a dry dock, shutting down a traffic lane and causing delays like those that occurred last August.
Once again, ACP officials found a European solution, where new locks on several canals accommodate post-Panamax ships. These locks, most notably the Berendrecht Lock in Antwerp, Belgium, employ two rolling gates, which are stored in recesses in the lock wall. The gate works like a wheelbarrow, with sets of wheels on the front and rear. When tilted forward in the recess, the gate slides across the chamber; when tilted backward, it returns to its recess. Most significantly, the twin-gate design allows canal crews to seal one of the recesses with a bulkhead and pump it dry, creating an on-site dry dock for maintenance and repairs. Meanwhile, the other gate is used to keep traffic moving.
For generations, seamen and cruise ship passengers have watched electric locomotives known as "mules" glide along lock-side tracks, pulling on hawsers to maneuver ships in the lock chambers. The new locks would have required 12 to 16 mules to position post-Panamax vessels. Instead, tugboats that already service canal traffic will align ships in the chambers -- one at the bow and one at the stern.
In conversation, canal officials make it clear that they see themselves as carrying on a grand engineering tradition. Speaking of the original builders, Alberto Alemán Zubieta, CEO of the ACP, says, "If you look at this canal through the eyes of an engineer, it is still so impressive what they did, how imaginative they were." He and other officials stress that, in contrast to the original construction, the challenges facing the expansion mostly involve well-known technologies. "If the Americans could build this whole canal in 10 years," Zubieta says, "we can finish this project in seven."
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Third Lane
The new locks' design conserves water -- vital even in tropical Panama.
Diagram by Dogo
Expansion plans for the Panama Canal call for two new sets of triple locks--one at the Atlantic entrance to the waterway and one at the Pacific. Although the new locks will be 65 percent larger than the current locks, the new design incorporates recycling basins that will reduce the amount of water for each transit by 7 percent. Currently, each transit flushes about 52 million gal. of fresh water -- enough to supply a city of 250,000 people -- into the Atlantic and Pacific oceans. |
The new locks will accommodate 1200-ft.-long post-Panamax ships displacing 170,000 tons and hauling up to 12,000 Twenty-foot Equivalent Units. One TEU is the cargo capacity of a standard shipping container. The current maximum capacity is 5000 TEUs. More cargo means more money: The Panama Canal Authority estimates a 35 percent increase in cargo volume through 2025 -- and additional toll revenues of $10 billion.
The recycling basins adjacent to each lock chamber are 1400 ft. long, 230 ft. wide and 18 ft. deep. The highest in each set is positioned slightly below the top of the lock chamber; the lowest is just above the chamber's minimum water level. Gravity funnels water from the basins and Gatun Lake through culverts in the lock walls, filling each chamber with 15 million cu. ft. of water and raising ships about 30 ft. in approx-imately 10 minutes. When vessels are lowered, valves reopen and gravity feeds 60 percent of the water back into the basins.
Instead of hinged miter gates, the new locks will use paired rolling gates, which have proved reliable at Pittsburgh's Davis Island Lock and Dam since 1885. The gates will roll out of wall recesses on tracks to seal the chambers. For repairs and maintenance, one gate will continue to operate while the other is returned to its recess, which is then sealed and pumped dry. Crews will work on site; traffic will still flow.
