Where does water go?

[Apec]

Guys I know the subject sounds silly, but I have a 20’ Speedster 2012. I understand the bilge pump, drain plug, and scupper valve are the 3 ways water is designed to exit the boat.
But which is deigned for what exactly? Engine takes on water, bilge pump removes. Engine compartment takes on water, drain plug assists bilge to remove water. But what about the scupper? This looks like the ski locker, and deck drain behind cockpit are direct piped to the scupper, is that right?

That’s what I thought but some evidence showed me today the deck and ski locker drains may drain into the engine bay.
Drain plug was clogged and found a piece of broken up paper clogged. This wouldn’t happen if only engine compartment water was used for drain plug. Is this correct?
I’ve heard many have problems with scupper valve not working correct and letting water in the deck drain, but with 6 people I have not seen this yet.
First boat of this size so still learning.
thanks

 

[Sno-Xr]

On my 04 Sppedster, the Ski locker drains into the engine bay, which means the bilge and drain plug take care of that. The passenger area drains through the scuppper tube and out the scupper valve, which happens automatically.

 

[MacSeaDoo]

I have a Speedster 150 and I would expect them all to be the same.

There are only 2 places for water to go with my boat.

All drains less the cockpit drain go to the hull, in which will be pumped by the bilge or drained when out of the water through the drain plugs. That for mine is each bin, and even the hole in the back where the hatch rotates into.

The cockpit has a drain that goes to the scupper valve next to the drive plumbing. This only works when underway because the valve is under water when the boat is stationary. As with any scupper valve, there is a floating ball that prevents the water from coming in.

When the boat is up on plane, the scupper is out of the water and gravity will drain it out.

On mine the Ski locker has a rubber gasket but I find it is not perfect and if you take one over the bow, you will get water in the locker, which means it is in the hull.