Cross-section of the Panama Canal

Why Build a Canal in Panama?

How the Panama Canal Works

U.S. Army Engineer Involvement

Canal Map
Map of the Panama Canal

Isthmian Canal Routes Explored
Miraflores Locks

Ship going through Gatun Locks
Passing through Gatun Locks

How the Panama Canal Works

The overall design of the Panama Canal was a controversial and contentious issue. In the early 20th century, many of the world’s foremost engineers believed the most efficient canals were those at sea level, which allowed vessels to transit unimpeded by locks. Most European canals, as well as the famous Suez Canal, were built at sea level. American civil and military engineers, on the other hand, had extensive experience designing and building lock and dam systems along America’s vast river network. These systems used locks to raise and lower ships into placid water controlled by dams and spillways. Not only were these canals more regulated than open straits between two large bodies of water, they also reduced the amount of excavation required. Instead of carving unnecessarily through the land, locks lifted vessels up and over the inland terrain. For Panama, the Army engineers, an influential group, supported a lock canal that would raise ships 85 feet above sea level into an enormous man-made lake that was impounded by dams on either end. By lifting ships into a lake, excavating down to sea level was not necessary, saving millions of dollars and years of work. Ultimately, President Roosevelt, Secretary of War Taft, and Congress agreed that a lock canal would be safer, more affordable, and faster to build than one at sea level.

To transit the Panama Canal, a ship entering from the Atlantic side at Colon would first navigate through roughly seven miles of dredged canal at sea level through marshy lowlands. At Gatun, the vessel would approach the enormous, sloping earthen dam that holds back the water in Gatun Lake. The vessel would then ascend a three-step lock and enter the man-made lake. From there, the next 32 miles of the journey to the Pacific Ocean would be upon the placid waters of Lake Gatun. After passing through the Culebra Cut, the lake would terminate at Pedro Miguel, where the ship would descend down a one-step lock into a small intermediary lake before descending the final two steps back to sea level at Miraflores. From there, the vessel would again navigate through another seven miles of dredged lowlands before entering the Pacific Ocean near Panama City.