The Panama Canal expansion project (), also called the Third Set of Locks Project, doubled the capacity of the Panama Canal by adding a new lane of traffic allowing for a larger number of ships, and increasing the width and depth of the lanes and locks allowing larger ships to pass. The new ships, called New Panamax, are about one and a half times the previous Panamax size and can carry over twice as much cargo. The expanded canal began commercial operation on 26 June 2016.
The project has: Built two new sets of locks, one each on the Atlantic and Pacific sides, and excavated new channels to the new locks Widened and deepened existing channels Raised the maximum operating water level of Gatun Lake
Then-Panamanian President Martín Torrijos formally proposed the project on 24 April 2006, saying it would transform Panama into a First World country. A national referendum approved the proposal by a 76.8 percent majority on 22 October, and the Cabinet and National Assembly followed suit. The project formally began in 2007.
It was initially announced that the Canal expansion would be completed by August 2014 to coincide with the 100th anniversary of the opening of the Panama Canal, but various setbacks, including strikes and disputes with the construction consortium over cost overruns, pushed the completion date back several times. Following additional difficulties including seepage from the new locks, the expansion was opened on 26 June 2016. The expansion doubled the Canal’s capacity. On March 2, 2018, the Panama Canal Authority announced that 3,000 New Panamax ships had crossed the canal expansion during its first 20 months of operation.
Background
The original Panama Canal has a limited capacity determined by operational times and cycles of the existing locks and was further constrained by the current trend towards larger (close to Panamax-sized) vessels transiting the canal, requiring more transit time in the locks and channels. Also, periodic maintenance on the aging canal requires shutdowns of the waterway. Demand is growing due to the growth of international trade, and many users require a guaranteed level of service. Despite the gains which have been made in efficiency, the Panama Canal Authority (ACP) estimated that the canal would reach its maximum sustainable capacity between 2009 and 2012. The long-term solution for the congestion was the expansion of the canal with a third set of locks.
The size of ships that could transit the canal, called Panamax, was constrained by the size of the locks, which are wide and long, and deep. The third set of locks allow transit of larger, Post-Panamax ships, which have a greater cargo capacity than the current locks can handle. The new lock chambers are wide, long, and deep. These dimensions allow for an estimated 79% of all cargo-carrying vessels to transit the canal, up from 45%.
All of the canal-widening studies since the 1930s determined that the best way to increase canal capacity is by building a third set of locks larger than the 1914 locks. The US began excavations for new locks in 1939, but abandoned them in 1942 because of the outbreak of World War II. This conclusion was again reached in the 1980s by the tripartite commission formed by Panama, Japan, and the US. More recently, the studies developed by the Panama Canal Authority () for its 2025 master plan confirm that a third, larger set of locks is the most suitable, profitable, and environmentally responsible option.
President Martín Torrijos, in a 24 April 2006 speech announcing the project, said that the canal "is like our 'petroleum'. Just like the petroleum that has not been extracted is worthless and that in order to extract it you have to invest in infrastructure, the canal requires to expand its capacity to absorb the growing demand of cargo and generate more wealth for Panamanians".