How was the Panama Canal built and completed and why was it constructed?

A torrent of mud swept down one side of the cut and up the other. Charles Gaillard, the engineer in charge of the Panama Canal, stood stock still, in a state of shock. The mudslide had wiped out several weeks' progress on the great project to link the Pacific Ocean and the Caribbean through the narrow isthmus of land that joins North and South America - so cutting sea routes from Europe to the Pacific by as much as 7,000 miles (11,300 kms). Gaillard called the chief of operations, George Goethals, over to inspect the damage. What are we going to do now?" he asked. Goethals shrugged, and lit a cigarette. 'Hell, dig it out again', he said.

It was January 1913. Gaillard and Goethals were standing beside part of the Culebra Cut, an 8-mile (13 kms) stretch of the canal that was being driven through the mountains of the continental divide between Bas Obispo and Pedro Miguel. The plan had been to blast a narrow defile through the rock, but the floor of the cut was soft and could not resist the mountain's weight pressing down on either side. As the cut was dug out, its walls collapsed and its floor swelled. Huge avalanches of mud swept away the workings - and the deeper the workmen got, the worse the falls became. In the end it would take around 28,000 tons of explosive to force the cut through the mountain.

A breeding ground for disease

Before the Americans began work, the Panama project had already defeated one great engineer: the Frenchman Ferdinand de Lesseps, who had been in charge of construction of the Suez Canal, in Egypt, between 1859 and 1869. His attempt to create a waterway across the Panamanian isthmus took eight years, cost $287 million and ended disastrously in 1889. Around 20,000 workers died, killed by yellow fever and malaria spread by mosquitoes. Panama was one of the least healthy places in the world.

In 1904, the leaders of the United States, long conscious of how a canal through Central America would reduce distances between east and west coast ports in the USA, decided to intervene. Their first step was to eradicate the political problems that had bedeviled the project. Panama was a province of Colombia, and the Colombian government would not agree to the canal's construction. President Theodore Roosevelt, who strongly supported the canal, encouraged a group of Panamanians to rise against Colombia and proclaim an independent republic; the price the new country had to pay was giving the US control of the area through which the canal was to pass. Next, Colonel William Gorgas, a US army doctor, set about wiping out the mosquitoes that had sealed the fate of de Lesseps' project. Gorgas repeatedly fumigated houses with insecticide, and prevented the females from laying eggs by clearing marshland and draining pools to deny the insects access to open water.

After three years preparation, construction of the canal began in 1907. It was a vast undertaking. At the Culebra Cut, work started at 7 AM every day except Sunday, after dawn trains had transported workmen to the site. All morning, gangs drilled holes for the dynamite that was used to blast through the rock, using more than 300 drills. At lunchtime, the drillers paused and the dynamite crews took over. In the afternoon crowds of workers, assisted by steam shovels, shifted the spoil into trains for removal. At 5 PM, the main force stopped work and the drilling and blasting continued. Every night, while the laborers slept in temporary townships, maintenance men checked the trains and shovels.

Lifting and lowering the ships

The Americans opted for two sets of locks, one to raise the ships to the level of Lake Gatun - lying about 85 ft (26 m) above sea level at the canal's Caribbean end - and the other to lower them again at the opposite end of the canal. These vast locks, cast on site, used 13.2 million cubic feet of concrete. Their floors were 13-20 feet thick and their walls, honeycombed with conduits through which water flowed to fill or empty the locks, were as much as 50 feet thick at the base.

The Panama Canal cost the American government $352 million - four times the price of the world's other great artificial waterway, the Suez Canal - and had claimed 5,609 lives from accidents and disease. Even so, it finished $23 million under budget, and opened six months ahead of schedule in August 1914. It was the first great construction project of the 20th century.