For the purposes of loadline marks, freshwater is considered to have a density of and typical seawater . Freshwater marks make allowance for the fact that the ship will float deeper in freshwater than saltwater. A ship loaded to her fresh water mark in fresh water will float at her summer mark once she has passed into seawater at the same displacement. Similarly, if loaded to her tropical freshwater mark she will float at her tropical seawater mark once she passes into seawater.