How do the Panama Canal locks raise and lower ships?

The Panama Canal uses a system of locks to raise and lower ships between the Atlantic Ocean, the Pacific Ocean, and the elevated Gatun Lake.1

The process relies on the gravity flow of water from lakes fed by the Chagres River and other waterways. When a ship enters a lock chamber, the gates are closed, and the chamber is either flooded or emptied to match the water level of the next section of the canal. This mechanism allows vessels to traverse the mountainous terrain of Panama and navigate the differences in tidal levels between the two oceans.21

To ensure safety during transit, larger vessels are guided by electric towing locomotives that keep them centered within the lock chambers. The system also incorporates protective measures, such as fender chains and secondary gates, to prevent damage to the lock structures. Recent expansions have introduced water-saving basins that allow for significant reuse of water while minimizing turbulence for transiting ships.2