The Panama Canal Authority will reduce the number of ships permitted through the strategic waterway from next month after El Niño-related drought lowered water levels. From September 3, daily transits will fall from a maximum of 36 to 34 vessels, before declining further to 32 on September 15. The canal links the Atlantic and Pacific oceans, and the restriction follows lower water levels in two artificial lakes that supply it.

Rainfall in the Panama Canal area was 34 percent below its historical average between May and August. Authorities fear El Niño could reduce rainfall further across Central America. They said lower-than-expected rainfall in the canal’s water-collection area made conservation measures necessary to protect the waterway’s long-term operation and sustainability. Authorities have already reduced the maximum permitted draft for large vessels.

About 5 percent of global maritime trade and nearly 40 percent of US container transport use the canal. Authorities said unbooked ships will face longer waiting times, while nine out of every 10 vessels using the canal are booked in advance. Further restrictions may be imposed depending on rainfall in the coming weeks. The lakes supplying the canal also meet water needs for nearly half of Panama’s 4.2 million people.