The boat is heavier for its size (usually an issue only when trailering)

同样尺寸的船只，若使用固定龙骨，重量会更大（只在用拖车拖船时才算是个问题）

This water can then be emptied when the boat is put on a trailer, to make it lighter for easier trailering.

当船被放在拖车上时，这些水可以被放掉，让船更轻，便于拖载。