The tops of trees and hills jut above the water. They were almost completely covered by water when engineers flooded the valley to create Gatun Lake. A special hyacinth patrol destroys more than 42,000,000 of these plants each year to keep the channel clear. The Gaillard Cut runs between Gold Hill on the east and Contractor's Hill on the west. The Gaillard Cut was originally called the Culebra Cut .
Dredges work constantly to keep the channel clear of earthslides.
In some years, the dredgers in the Gaillard Cut remove as much as 1,000,000 cubic yards of earth. After the ship steams out of the Gaillard Cut , electric locomotives pull it into the Pedro Miguel Locks . These locks lower the vessel 31 feet in one step to man-made Miraflores lake. Here, two chambers lower the vessel to the level of the Pacific Ocean. The distances these chambers must lower the ship depends on the height of the tide in the Pacific.