Dry cargo is stored close to the wharf. It may have been delivered by train, truck or another ship. It may be stored outside, in large sheds or silos. Conveyor belts, grabs on the ends of cranes or pumps can be used to fill the holds.
While filling the holds, dust from the cargo is not allowed to escape into the air. It is important that the cargo is spread evenly in the hold and can't move if the ship is hit by large waves. If the cargo moves to one side of the ship, the ship may no longer be balanced and may start to lean over. This is described as a list.
Oil and chemical cargoes are stored in tanks on the shore. Pipes run from the tanks to the pier or wharf. These pipes are connected to the ship using large hoses. Valves in the hoses and on the ship prevent any liquid escaping and causing pollution. When the hoses are connected to the ship's pipes, the valves are released and the fluid is pumped into the ship's tanks.
As ships are loaded they become heavier. Ballast water is pumped out of the ship to compensate for the extra weight of the cargo.