What Is a Watermaker?
A machine that turns seawater into fresh water by forcing it through a membrane at high pressure - the freedom of longer passages, for the kit that sulks when left idle.
A watermaker is a system that turns seawater into fresh water by pushing it through a reverse-osmosis membrane with a high-pressure pump. It solves the tank headache: instead of planning marina water stops from bay to bay, it gives you the freedom of a shower at anchor. But it has a clear temperament - it wants to be used regularly.
The key to the decision is how often you use the boat. The table below shows whether it makes sense for different user profiles.
Who a watermaker suits
Usage profile | Watermaker |
|---|---|
Lives aboard, mostly at anchor | A game-changer, freedom |
Weekend user once a month | Usually an expensive regret |
Long passages, remote anchorages | Very worthwhile |
If a membrane sits idle, biological growth starts; if it will be out of use for more than a few days, it is laid up with preservative fluid (pickle). The classic fate of a system left standing is membrane failure, and the membrane is the watermaker's most expensive consumable part.
Space matters too: the pump, membrane and filters need serious locker volume; mounting the vibrating pump on the cabin wall beside the berth is a recipe for regret the first night. Water is made in clean anchorages, not in dirty marina water.