The aft shower sump is located beneath the sole hatch board at the bottom of the companion way ladder. It has a sump pump with float switch, but no seacock, that discharges above the water line port side through hull. A shower sump switch on the power panel must be activated for it to operate properly.

Our sit tub drain stopper will pop up to allow water to flow to the sump. We use the shower almost every day during the cruising season. The drain will become clogged with gunk (soap, hair, etc.) after a period of time. Draino seems to work pretty well on ours. After the Draino has set in the drain line for the designated period of time I will normally use a plunger to agitate the line to break loose any stubborn material. Flows freely after that.

It helps with the agitation if the drain port on the sump side is covered with water. You have to shut the sump switch off to get this level of water in the sump. One other consideration. The sump pump will not get all the water out. After a cruise I first use a plastic cup to remove the majority of sump water, then a kitchen baster or sponge to remove any remaining waste water, otherwise the soapy residue will rot and stink up the boat after a week of warm weather.