Water under cabin stairs - 3100 Offshore

[BigGame]

I have a 2005 3100 Offshore (inboards). Under the cabin stairs is a basin that contains a sump pump, and the sump has inlet hoses for both the shower drain and the forward bilge. My problem is that water is accumulating in the basin itself, not just in the sump pump. Not a lot of water, maybe 3 gallons, but enough to make it smell pretty nasty in the cabin. Any ideas where this may be coming from?

In the basin itself is a hole that was cutout where the hose from the shower drain and forward bilge come through...and the water is coming in from that cutout. Any suggestions on how to take care of this?

Thanks in advance!

[Walkingtuna]

I know exactly what you are talking about. I don't know where water is coming from, but I add some bleach and drain it often to keep it smelling fresh.

[BigGame]

Thanks Walkingtuna. Someone mentioned removing the sump pump all together (I'm never going to take a shower in that head anyway) and replace it with a bilge pump to keep the water level in that basin down. I hate the smell of bleach, but it's probably better than the funk that's there now....

[jcamp4]

I pulled the shower pump out and found some of the water was coming up from the screws that held the pump in place and also fro the drain hole in the rear of the compartment I sealed all of these and drilled a two inch hole in the bottom of the compartment till I hit the solid fiberglass hull beneath
. I vacuumed out all the water that was down there several times throughout the season and sealed with a two inch expanding rubber plug. Now I can get water out as I need to. Compartment has been dry ever since. Also had to replace badly leaking scuppers a rear of boat. I think water was getting in there whenever boat rocked and scuppers took on water. Water came in thorough scuppers into boat but a lot of it went right into the rear bilge and would set off rear bilge pump,often in rougher conditions. Since this fix I have had very little water in hull beneath liner.

[MarkT]

I had the same problem with my 1999 30 Express. It came from two areas. The head sink and shower drained into the sump pump. The top was not on tight and allowed water to slosh over. And after sitting for some time it grew moldy and smelled. The second and biggest factor was the limber hole allowing water to flow forward from the engine room, especially when the fuel tanks were not full allowing a stern high / bow down attitude at rest. Water ran forward.Washing the boat, rudder seal leaks and any other way water got into the bilge it would run forward. I was able to put a bilge plug there and that stopped all water from running forward. I also check the sump pump regularly to make sure it does not contain water, I even sponge it out.

[BigGame]

Thank you all. I did find that my scuppers are leaking into the aft bilge, and that water does drain forward when the boat is at rest. I'll fix that first and see if that's the issue, or if there are more areas tof look at.

[Estimator]

check the anchor locker as well. known to leak into the cabin

[BigGame]

Thanks. I'm going to check the anchor locker tomorrow. I've been able to keep the sump basin dry by blocking the tube that connects it to the engine room bilge (that water was running forward into the sump pump basin), but I also have water under the cabin floor. You can see it if you remove the access plate in the sump pump basin. It appears to be fresh water, so it would make sense that it might be coming from the anchor locker.