Why was the Panama Canal expanded with the Third Set of Locks Project?

The Third Set of Locks Project was initiated primarily because many supertankers and large naval vessels were too large to pass through the original canal locks.1

By adding two new sets of three-step locks, the project effectively doubled the canal's capacity and enabled the passage of a new generation of supersized ships, known as "neo-Panamax" vessels, which can carry up to 13,000 TEUs. Beyond accommodating these larger ships, the expansion included widening and deepening navigational channels and increasing the usable water reserves of Gatún Lake to support the increased traffic. The project was chosen over the alternative of building a new sea-level canal at a different location due to lower costs and fewer environmental concerns.1