How to clean the waste tank

Every year, there are questions about how to deal with a clogged waste tank. That`s why Jirka Zindulka wrote an article about how to clean it.

Our flotilla sailing holiday with the children ended on Saturday morning and when we returned to the boats, the charter company technician announced that the waste tank on the Sun Odyssey 43 DS boat was blocked and, that unblocking the tank would cost EUR 150. It annoyed me a little that the boat’s skipper didn’t tell me about this earlier as unblocking a blocked waste tank takes five minutes, but it is advisable to not do this job in the marina or at least, not during the day. I told the technician that I would unblock the tank myself and that it was a simple task. He told me to go ahead.

Unblocking a waste tank really is a simple task. Waste tanks get blocked regularly on older boats. You must not throw any toilet paper into the toilet. But though you may tell that to the crew several times a day, somebody will still throw some paper in there. The best solution is to go to the toilet in the sea. Swim far out into the sea using slow strokes, relax properly during your swim and then, empty your bowels into the sea in a nice relaxed manner. There is a bidet all around and you don’t need any toilet paper. And then swim back to the boat in the same relaxed manner.

But back to the unblocking of the blocked waste tank. So just how do we go about it? You will need to take a water hose, get in a dinghy and sail around to the side of the boat to the flange through which the contents of the waste tank are flushed into the sea, and fit the water hose to this flange (this flange is usually about 30cm below the surface, so you can insert the hose into it from the dinghy). The hose must be inserted as far as possible, and marked to show how far it can be inserted and then pulled out and bound with silver tape or electrician’s tape to seal the hose in the flange.

Then all you have to do is stand one person on the breakwater by the water tap which the hose is attached to, and another person in the bathroom by the shut-off valve from the waste tank. In the dinghy, I inserted the hose into the flange under the water and firmly pressed it to the flange (where I had wrapped it with tape) to ensure a perfect seal. I then called to the breakwater for the person standing there to turn on the water. I felt the water bubbling in the hose, I heard the air bubbling in the water tank and then, I felt how some of the contents of the waste tank, pushed by water from the hose like a piston, shot out of the bleeder valve located about a metre above me and part of the stinky content hit my back in a very elegant arc, ran down my white t-shirt onto my clean shorts and immediately admitted me to the ranks of the stinky faeces collectors.

Disgusted, I yanked the water hose from the flange and faeces started to flow abruptly into the clean harbour water. The sea turned brown and I shouted out “close the waste tank”. Pavel, in the bathroom, closed off the valve at lightning speed and the brown spillage stopped increasing in size. I inconspicuously sprayed water from the hose over the brown spillage to push it away from the boat. It soon disappeared. The waste tank was unblocked (mission accomplished) but I smelled of faeces. Climbing back onboard, I met Jana. When I passed by her, she took a step back in disgust and asked why I smelled so disgusting. I muttered something about my new special deodorant and went for a shower.

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