A calm day at sea: it’s half past one in the afternoon. Only a few people are on deck, the other watches are taking a rest. A whale casually swims by, giving joy to those lucky few on deck. And the watch continues.

‘This looks strange, doesn’t it?’, the deckhand sais to the officer, showing him the jug of water just coming from the tap. The jug was, supposedly, filled with water. However, it looks more like lemonade. The engineer just walks by the aftdeck. ‘What do you think of this water?’ The officer shows the jug to the engineer, who looks doubtful. ‘I think I’ll have a look at the water maker.’ And he walks off to the pump room.

The water maker can make brilliantly clear water. Sea water comes into the system, is put under high pressure and forced through a membrane with tiny holes. Water molecules are small enough to pass through, but salt cannot. And with that, clear and fresh water is made. However, something is not working properly at the moment.

In the pump room the engineer quickly notices that the pressure in front of the membrane is too low. When the seawater comes in, it passes through several filters, one of them being a 5 µm filter. This could be clogged and causing the problem. The engineer, unaware of what was to come, opens it. The stench coming from the filter is beyond anything the engineer had smelled in his life (and that says a lot, considering the shitty jobs he sometimes has to do). The problem had been located, but what had happened?

According to a fair number of blog posts (with names such as ‘a whale ruined my water maker’), the droppings of whales are a serious cause for water maker failures. The excrements clog up the system, ending up in poorly filtered water.

The engineer replaces the old filter and solves the problem. The sailing continues, the old watch goes off, the new watch takes over. A deckhand looks across the water. ‘Look a whale! O no, wait, it’s just a dolphin.’ Do you also want to experience sailing with these animals? View our voyages here >