My new boat has a deep sink.where used water goes?in to belch??

Question

'new boater'

Answer 1

There are two places neither is the bilge. Either overboard or to a holding tank that should be pumped out after every trip. Overboard is not legal for grey or black water on small pleasure craft. It's called water pollution.

Answer 2

The "bilge" is the lowest place in the hull and water that enters the boat collects there, and is pumped out by the bilge pump(s) into the sea (or lake).

Used water from a head (lavatory, toilet) or galley (kitchen) should be stored on board and disposed of properly.

Answer 3

It goes over board. You should find a thru hull fitting on the outside of the boat close to where the sink is on the inside.

Answer 4

Just to follow up on a few of the above answers.

Usually it goes overboard.  This can be below the water line or above.   Sometimes it goes into a holding tank.   One also never knows what a previous owner has done.

Go below your sink and trace the line from the drain.   It probalby goes fairly straight down to a through hull with a valve on it called a seacock.  As others have said, it's a good idea to close this when you are off the boat.    Also, check this to make sure it indeed does close and is solid.    A faulty through-hull can sink a boat quickly.   I recommend you check all your boats through hulls which may include the head intake, maybe a head out.  If you have an inboard, there will be a raw water in there as well.  Its also a good idea to have some wood plugs that you can plug your thru-hulls with if you ever have a failure.  I tied one to each through-hull with a short string so it's always there.

If your sink is well above water line, it's possible there is a drain above the water that does not require a seacock.  This is more common with trimarans and catamarans than with monohulls.