Spawn on a beach in Rust and the first thing to run out is usually water. The sea is right there, but drinking salt water makes you thirstier. The Water Purifier fixes that: it turns salt water into fresh water you can drink or pour on your crops.
There are two of them. The cheap Water Purifier sits on a campfire and is known from the start. The Powered Water Purifier runs on electricity, is twice as efficient and is the heart of every sea side farm. This water purifier Rust guide covers both: craft costs, how to use them, the salt water farm setup, which one to pick and how easy they are to break.
- What It Is
- Stats
- Craft a Purifier
- How to Use It
- Powered Purifier
- Farm Setup
- Which to Use
- Raid Cost
- Tips
- FAQ
What Is the Water Purifier in Rust?
In Rust you lose hydration all the time, faster when it is hot or when you run. Fresh water from a river, lake or a water catcher tops it back up. Salt water from the sea does the opposite and drains your hydration, so you cannot rely on the ocean without cleaning it first. Our Rust water guide explains hydration and every water source in detail.
The game’s own description of the Water Purifier is “Place overtop of a campfire. Will provide clean, drinkable water from salty, or stagnant water.” The Powered Water Purifier is described as “a device that converts salt water to fresh water while powered”. The first one is for drinking, the second is for running a farm.
Water Purifier Stats
| Stat | Water Purifier | Powered Water Purifier |
|---|---|---|
| Craft cost | 15 Metal Fragments, 10 Cloth, 1 Empty Propane Tank | 300 Metal Fragments, 100 Wood, 20 Cloth |
| Workbench | None | Workbench 2 |
| Blueprint | Default, known from the start | 30 scrap on the Workbench 2 tech tree or at a research table |
| Craft time | 30 s | 30 s, 15 s at a Workbench 3 |
| Runs on | A lit campfire under it | 5 rW of electricity |
| Salt to fresh ratio | 4 : 1 | 2 : 1 |
| Processing speed | About 1,000 ml of salt water a minute | About 4,000 ml of salt water a minute |
| Water storage | 5,000 ml | 5,000 ml |
| Health | 150 HP | 300 HP |
| Stack size | 1 | 3 |
| Recycles into | 9 Metal Fragments, 6 Cloth, 60% chance of the Propane Tank | 180 Metal Fragments, 60 Wood, 12 Cloth |
| Shortname / Item ID | water.purifier / 2114754781 | powered.water.purifier / -365097295 |
Both item IDs are also in our Rust item IDs list if you run a server and need them for admin commands.
How to Craft a Water Purifier in Rust
Every player knows the Water Purifier blueprint from the start, so there is nothing to research. Open your crafting menu and make it with:
- 15 Metal Fragments, from smelting a little metal ore in a furnace.
- 10 Cloth, from hemp plants or by recycling a tarp.
- 1 Empty Propane Tank, a component you find in roadside barrels and crates. Keep one in your stash early in the wipe.
It takes 30 seconds and needs no workbench, so you can make one on your first beach run.
How to Use the Water Purifier
- Place a campfire on flat ground, ideally inside your base near the shore.
- Place the Water Purifier on top of the campfire. It will not work anywhere else.
- Fill it with salt water. Carry sea water in a Water Bucket, Water Jug or Small Water Bottle and pour it in. It holds up to 5,000 ml.
- Add wood to the campfire and light it. As the fire burns, the purifier boils the salt water and fresh water collects inside.
- Collect the fresh water into a container to drink, or carry it to your planters.
Four parts salt water make one part fresh, so a full 5,000 ml load gives you about 1,250 ml of drinkable water. That is plenty for one player, but far too slow to keep a farm watered.
The Powered Water Purifier
The Powered Water Purifier skips the campfire and runs on electricity instead. Unlock it for 30 scrap on the Workbench 2 page of the tech tree, then craft it at a Workbench 2 from 300 metal fragments, 100 wood and 20 cloth.
It has three connections: Water In, Water Out and Power In. Hose salt water into it, give it 5 rW, and fresh water comes out the other side at 2 salt : 1 fresh. That is twice as efficient as the campfire purifier and much faster, because it can process about 4,000 ml of salt water a minute. A small solar panel setup with a battery, or a Water Wheel in a river, powers it easily.
Salt Water Farm Setup
If your base is by the sea, this is the standard way to water your planters automatically:
- Two Water Pumps in the ocean, 5 rW each. Two are used because the purifier throws away half of what goes in.
- One Powered Water Purifier takes both pump lines through its Water In and outputs fresh water.
- An optional Water Barrel after the purifier stores a buffer, so a short power cut does not dry out your crops.
- Up to 4 sprinklers on the fresh water side keep your planters watered.
Connect everything with the Hose Tool from Water Out to Water In. The whole line draws 15 rW, five for each pump and five for the purifier. If your base is on a river or lake you can skip the purifier completely, because a pump in fresh water feeds sprinklers directly.
Which Water Purifier Should You Use?
| You want | Use | Why |
|---|---|---|
| Drinking water on a beach spawn | Water Purifier | Cheap, default blueprint, no power needed |
| Water for planters by the sea | Powered Water Purifier | Twice the output per litre, hoses straight to sprinklers |
| Water near a river or lake | Neither | That water is already fresh, pump it directly |
| Water with no source nearby | Water catchers | They fill from rain and fog with no purifier |
How to Break a Water Purifier
| Method | Water Purifier (150 HP) | Powered Purifier (300 HP) |
|---|---|---|
| Satchel Charge | 1 | 1 |
| Rocket | 1 | 1 |
| Molotov | 1 | 1 |
| Beancan Grenade | 3 | 5 |
| Explosive 5.56 Ammo | 17 | 34 |
| Hatchet | About 11 seconds | About 22 seconds |
| Jackhammer | About 3 seconds | About 6 seconds |
Both are cheap to lose, so keep them inside your walls. For the cost of the walls and doors in front of them, use our Rust raid calculator.
Water Purifier Tips
- Use fresh water first. A river, lake or water catcher gives fresh water with no purifier at all. Purifiers are for bases on the coast.
- Never drink straight from the sea. Salt water lowers hydration, and on a fresh spawn that can kill you.
- Save a propane tank. Empty propane tanks come from barrels and crates. Grab one early so you can craft a purifier the moment you need it.
- Buffer the farm line. A Water Barrel after the Powered Water Purifier keeps sprinklers running if your power dips at night.
- Watch your power budget. A salt water line uses 15 rW. Plan your solar panels, batteries or wind turbine around it.
- Loot fresh water at monuments. The Water Treatment Plant and Fishing Villages are good stops on a coastal loot run.
Rust Water Purifier FAQ
How do you make a water purifier in Rust?
Craft it from 15 metal fragments, 10 cloth and 1 empty propane tank. It is a default blueprint, needs no workbench and takes 30 seconds.
How does the water purifier work in Rust?
Place the Water Purifier on top of a campfire, fill it with salt water, then light the fire with wood inside. It turns 4 parts salt water into 1 part fresh water and holds up to 5,000 ml.
How much power does a powered water purifier use?
The Powered Water Purifier uses 5 rW. A full salt water line with two Water Pumps and one purifier needs 15 rW.
What is the ratio of the powered water purifier?
The Powered Water Purifier converts 2 salt water into 1 fresh water. The campfire Water Purifier converts at 4 to 1, so the powered one is twice as efficient.
Where do you get an empty propane tank in Rust?
Empty propane tanks are a component found in roadside barrels and crates. You need one for each Water Purifier you craft.
Do you need a water purifier for river water?
No. River and lake water is already fresh, so you can drink it and pump it straight to sprinklers. Purifiers are only needed for salt water from the sea.
How many explosives does it take to destroy a water purifier?
One satchel charge, one rocket or one molotov destroys either purifier. The campfire Water Purifier has 150 HP and the Powered Water Purifier has 300 HP.