How the Panama Canal Works

A Lock System That Defies Gravity

Unlike a sea-level canal such as Suez, the Panama Canal operates through an ingenious lock system that lifts ships 26 meters (85 feet) above sea level to Gatún Lake, an artificial lake of 425 km² created by damming the Chagres River. Ships ascend at one end, navigate across the lake, and descend at the other.

The Original Locks (Panamax)

The original system, completed in 1914, consists of three sets of locks. Gatún Locks on the Atlantic side have three chambers lifting ships from Caribbean sea level to Gatún Lake in a single 26-meter ascent. Pedro Miguel Locks on the Pacific side consist of a single chamber lowering ships 9.4 meters to Miraflores Lake. Miraflores Locks complete the descent with two chambers lowering ships 16.5 meters to Pacific Ocean level.

Each lock chamber measures 33.5 meters (110 feet) wide by 305 meters (1,000 feet) long — dimensions that defined the Panamax shipbuilding standard for a century. The gates, made of steel 2 meters thick and up to 25 meters tall, weigh between 350 and 730 tons each.

The Transit Process

A complete transit takes between 8 and 10 hours. The process relies exclusively on gravity: no pumps are used to move water between chambers. When a ship enters a chamber, the gates close behind it and valves at the bottom of the side walls are opened, allowing water to flow by gravity from the upper chamber into the lower one. The ship rises or falls gently with the water level. Each transit uses approximately 197 million liters (52 million gallons) of fresh water from Gatún Lake.

The New Neopanamax Locks (2016)

Inaugurated on June 26, 2016, the new Agua Clara (Atlantic) and Cocolí (Pacific) locks represent a masterpiece of modern engineering. Measuring 427 meters long by 55 meters wide, they can handle vessels up to 366 meters in length and 49 meters in beam — triple the cargo of a traditional Panamax vessel. Each chamber features three lateral water-saving basins that recycle 60% of the water used in each transit, making the new locks more efficient than the originals despite their larger size.

Gatún Lake and the Culebra Cut

Gatún Lake, created between 1907 and 1913 by building the Gatún Dam across the Chagres River, provides the water to operate the locks and constitutes 33 kilometers (20.5 miles) of the Canal's total length. The Culebra Cut, a 13.7-kilometer (8.5-mile) channel excavated through the Continental Divide, was the greatest engineering challenge of the entire construction due to constant landslides.