Marine bilge pumps are a type of marine water pump found on both large and small leisure boat or yachts. They are responsible for removing water accumulating bilge wells and throwing it overboard.
Most of the time,water that collects in the bilge is incidental:
*It could be rain water or water from spray collection in the boat
*Wash-down water that collects in the bilge while the boat is being cleaned.
*Or water from built-in coolers,the lips around large hatches.
The bilge is an area that is usually below the deck and allowed to have a little bit of water collect in it. When the water level gets too high in the bilge, the pump kicks on to pump that water out of the boat.

1.Bilge pumps prevent Flooding.
Leakage,drainage and washing down fluids all find their way to the bilge wells of ships. If the oily water rises, it may get to machinery and damage them. Also ,if one compartment floods, this will affect the balance of the boat.

For recreational boats, without deep bilge wells, all it takes is a little excess water to get to boat’s electronics. Heavy rain or big waves maybe all it takes to destroy your boat’s system.
Most boat bilge pumps come with an automatic float switch. This switch turns the pump on whenever water rises above a certain level. This way,don’t always have to check the bilge.

2.Bilge pumps can save the ship from Sinking.

3.Bilge pumps are required by law.