The reduction, the fourth one of 2019, was based on the projected levels of Gatun Lake in the coming weeks, according to a Panama Canal Authority shipping advisory. Ships arriving after the effective date with draughts larger than the maximum size may still be allowed to transit depending on the actual level of Gatun Lake at the time, but otherwise the vessels will be required to trim or offload cargo.
Draught adjustments will be announced in 12-inch decrements generally with at least four weeks of advance notice.
In January, the authority announced the first reduction, which was effective mid-February, because rainfall registered in the Panama Canal watershed in December was about 90 percent below the historical average, which caused the water levels of Gatun and Madden lakes to fall below the expected level.
The most recent reduction is set to become effective 16 days after the draught is reduced to 47 feet.