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September 5, 2026

Building a Camper Van Water System: Fresh Water, Filters and Waste Water

Wassersystem im Camper selber bauen: Frischwasser, Filter und Abwasser

Written by Evelynevanlife

Humbär's water system

Advertisement. This post contains advertising links (affiliate links) to Alb Filter. If you order through them you get a discount and we get a commission. The price stays the same for you, so nothing extra to pay. It does not change what we think of the system either: everything here has been fitted in our own van for years.

water running from the tap in our camper
Water running from the tap

Our van has a high-quality, modern water setup. Thanks to our filter system we get very good water quality wherever we are, and thanks to a generous fresh water tank we can stay off-grid for several days. The system is comparatively simple, and we were able to put it together ourselves with no previous experience in this field. Here you can read what our water system consists of, how it is built, and what we have learned from living with it.

We built ours into a VW LT35, but nothing about the setup is tied to that van. It is made of parts anyone can buy, and it carries over just as well to any other campervan, panel van or motorhome. What changes from vehicle to vehicle is mainly the size of the tanks and where they can sit.

The short version, if you are only here for the filters

We filter with the Alb Filter Pro Camper set, plus the Protect pre-filter while filling up and the Nano germ barrier before the tap. Through our link you currently get 10% off.

To the Pro Camper set with 10% off (ad link)

10% instead of 5%: Alb Filter has raised the discount for our readers for a limited time. The 10% runs until 8 October 2026, after which it goes back to a permanent 5%. The discount code is weltenhummler.

Our setup, simple and dependable

sketch of the water system built into our campervan

A sketch of the water system we built in

a public water point with two taps, hoses and a cat sitting on the ledge
Filling up at a public water point, under supervision

The fresh water runs through a tap adapter and our water meter into the water hose. Before it reaches the fresh water tank it passes through a Protect pre-filter. This holds back larger particles such as sand or sediment, and in doing so it also protects the filter stages that follow.

The water then runs through an Active cartridge with activated carbon. Among other things, this reduces chlorine, substances affecting taste and smell, various organic pollutants and other unwanted substances. The filtered water then reaches our fresh water tank, where it is stored.

As soon as we need water, we switch on our water pump. It moves the water out of the fresh water tank into our pipework and builds up the pressure needed for the water to flow evenly from the tap. After the pump, the water passes through the Nano germ barrier - a hollow fiber membrane that mechanically holds back germs and bacteria. From there it flows through our mixer tap and out of the faucet.

The used water then drains through the siphon. The siphon forms an odor barrier, because there is always water standing in it. From there the waste water runs into our underfloor waste water tank.

the drain into the waste water tank under the vehicle

The drain into the waste water tank under the vehicle

demonstrating how the tank empties, using fresh water
Demonstrating how the tank empties, using fresh water

Tank electrodes and an LED display let us check the level in both tanks. Once the waste water tank is full, we can empty it through a valve at a suitable gray water disposal station.

For now we decided against a hot water installation. A boiler or an instantaneous water heater could in principle still be retrofitted later. For that, our pipework would have to be extended and the water routed to the heater or to a mixer tap. As things stand, we therefore do not use the hot water side of our mixer tap either.

Clean, drinkable water, any time

a drinking water spring in greece
A drinking water spring in Greece

Being as independent and flexible as possible with our drinking water matters a lot to us on the road. We make a point of taking water only from designated drinking water sources. Our filter system then gives us one more stage of filtration before we drink it.

With water from sources like these, we drink it straight from our tap after filtering and do not need to boil it as well.

clean drinking water thanks to alb filter

Clean drinking water thanks to Alb Filter

We filter our water with high-quality water filters from Alb Filter. Depending on the cartridge used, chlorine, microplastics, pharmaceutical residues, pesticides and PFAS can be reduced or held back. At the same time substances affecting taste and smell can be reduced, which can also improve the taste of tap water.

Another advantage for us: the filter cartridges we use are designed so that valuable minerals stay in the water.

And as a nice side effect, we save a great many single-use bottles on the road and can simply prepare our own water.

How the filters work

the pro camper set from alb filter, as delivered
The Pro Camper set from Alb Filter, as delivered, with its two stainless steel housings

You order the set you need for your project once. In our case that was the Pro Camper set from Alb Filter, for a permanently installed filter system in our vehicle. Alb Filter also offers systems for the home as well as travel filters that do not have to be installed permanently and are easy to take along.

The set contains everything we need for the installation, including a first set of filter cartridges. That also includes the high-quality stainless steel housings the cartridges are fitted into. The Protect pre-filter, which we hang on the hose while filling up, comes in two versions: the aluminium one in a blue housing, which is what we have, and a stainless steel one.

After that, all that is needed is to replace the cartridges regularly, depending on use and water quality.

How long the filters last

How long a cartridge can be used depends among other things on how much water flows through it and on the quality of the water going in. The more particles or other substances the water carries, the harder the filter has to work.

With every new cartridge, Alb Filter includes a small card where we can note the date we put it into service. That way we keep track of when a cartridge went in.

The flow rate can be another sign that a filter should be changed. If the water flow becomes noticeably slower, that can point to a clogged filter.

We also look at the filters themselves regularly. If our pre-filter is heavily soiled, for instance, we swap it out.

As a rough guide we go by the replacement intervals given by the manufacturer. Actual service life can vary with use and water quality.

With the pre-filter in particular we notice how much difference water quality makes. Those three months are therefore our own experience, not a generally valid figure.

If you are working out how often you will need to reorder: replacement cartridges come with 10% off using the code weltenhummler (until 8 October 2026, 5% after that).

Replacement cartridges with 10% off (ad link)

Tank cleaning and hygiene

A good filter system alone does not make a hygienically sound water system. The fresh water tank, the pipes, the fittings and the tap all have to be kept clean and washed out regularly.

Precisely because our water stays in the tank for several days, cleaning the system is as much a part of water hygiene for us as changing the filters. We get our cleaning agent from Alb Filter too, the Alb Clean tank cleaner, and can warmly recommend it.

If you are planning your own water system, we would not only invest in good filters but also build the whole system to be as hygienic and as easy to reach as possible.

If there is one place in your van conversion not to save money, it is here. Especially when you travel a lot, water quality can differ from source to source and from country to country. We would rather not simply trust that water coming out of a tap somewhere automatically has the quality we want for our drinking water.

Where to find the water filters

To the Alb Filter water filters with 10% off (ad link)

10% off with the code weltenhummler, until 8 October 2026. A permanent 5% after that. Ordering through our link saves you money and at the same time helps us keep traveling with Humbär for a long time to come. That really would make us very happy!

Straight to the individual products: Pro Camper set · Protect pre-filter · Active cartridge · Nano germ barrier · Alb Clean tank cleaner

The full parts list

From fresh water to waste water: everything built into Humbär's water setup, sorted by function.

Fresh water: tank and supply

  • Fresh water tank: 84 l, rear right in the vehicle
  • Water filler neck: Lilie, white
  • Hose clamps: Lilie, seawater resistant, 12-22 mm, pack of 2
  • Universal water connector: HEOSwater Connector (5251)
  • Water hose: Gardena complete set, suitable for drinking water
  • Tap connector: Gardena, 21 mm (G 1/2 inch)
  • Tap adapter for indoor taps: Gardena
  • Water meter: Gardena AquaCount
  • Pre-filter: Alb Filter Protect pre-filter and Alb Filter Active activated carbon cartridge
  • Tank electrode: Votronic 15-50 K
  • Fresh water tank gauge: Votronic LED bar display, 12/24 V
  • Tank connection fitting: angled, 40 mm

Fresh water: outlet

  • Pressure pump: Lilie Soft series LP4142, 11.3 l/min, 2.1 bar

  • Alb Filter Nano germ barrier: Nano germ barrier from the Alb Filter Pro Camper set

  • Drinking water hose: Lilie Native, 10/16 mm, blue, cold water, 5 m

  • Y-piece: 10 mm, with 2 shut-off valves

  • Hose tails: 2 x 3/8 inch, household tap to 10 mm hose

  • Tank cleaner: Alb Clean, for the fresh water tank and the pipework

Sink and kitchen

  • Sink: IKEA HAVSEN
  • Siphon: IKEA Lillviken
  • Cover cap: IKEA Lillviken
  • Tap: IKEA Glittran

Waste water

  • Waste water tank: 53 l, underfloor (sold as a water tank for the VW T4, 1990-2003)
  • Mounting kit: for water tanks
  • Waste water valve: 3", SB
  • Tank electrode: Votronic 12-24 K (waste water)
  • Waste water tank gauge: Votronic S, 12/24 V, LED bar display

Shared between fresh and waste water

  • Tank connection fitting: straight, 40 mm
  • Spiral hose: 2 x ultra-flexible, 40 mm
  • Elbow fittings: 4 x for water outlets
  • Hose clamps: 4 x worm drive, 30-45 mm

Deliberately left out

  • Hot water: no boiler and no instantaneous heater, though both could be retrofitted
  • Shower: a solar shower on the outside of the van instead of a wet room inside

All components are matched to one another for a self-sufficient fresh and waste water system. Ours sit in a VW LT35, but the same setup carries over to any other camper or motorhome conversion.

Questions and answers

How big should the water tanks in a camper be?

That depends entirely on how much water you use, what you have planned and how big your camper is.

We built in an 84 l fresh water tank and a 53 l waste water tank. We are very happy with the amount of fresh water. It lets us stay off-grid for up to a week if we use it sparingly.

That said, we like washing dishes with a bit more water, we occasionally use it for showering too, and so we prefer to change our fresh water about every five days.

Our waste water tank sits underfloor. We would have liked it a little bigger - around 70 l would have been ideal for us - but the way our vehicle is built, that unfortunately was not possible.

So it is usually not the fresh water but the waste water that forces us to find a disposal station. With the way we use it, though, our waste water tank also lasts a good four to five days.

How do you fill a fresh water tank?

our gardena water hose
Our Gardena water hose

For filling up we use our Gardena water hose, which is suitable for drinking water.

At the water source we fit a matching adapter, to which we then connect our water meter and the hose. It pays to carry adapters in several diameters, because connections differ from country to country and from source to source.

We also carry a tap adapter for indoor taps. With it we can fill up even when our adapter will not connect directly to the tap.

At the other end of the hose we fit our Protect pre-filter and the Active cartridge from Alb Filter. That way the water is already pre-filtered while the tank is filling, with various unwanted substances reduced and particles held back before it ever reaches our fresh water tank.

How does the water get from the tank to the tap?

our water pumps: the old one on the left, the new one on the right
Our water pumps: the old one on the left, the new one on the right

We built in a pressure water pump, which we switch on with an on/off switch.

The pump moves the water out of the fresh water tank into our pipework and builds up the pressure needed. That is what lets the water flow evenly from our tap.

After the pump, the water passes through the Nano germ barrier. The hollow fiber membrane inside it mechanically holds back germs and bacteria.

From there the water goes through our mixer tap and out of the faucet.

How do we shower in vanlife?

Because our vehicle only offers limited space, we decided against a shower inside.

Instead we carry a simple solar shower that we can hang on the outside of the van. When it is colder, we heat the water in our kettle and then pour it into the solar shower.

When showering outdoors we make sure to use biodegradable products and to keep a good distance from any body of water.

We also quite like visiting a public shower now and then, going to an indoor pool, or using our emergency shower - for which we simply turn our big kitchen sink into a small "shower".

wellness in the sea

Wellness in the sea

How did we manage to fit an ordinary household tap in the camper?

The installation is fairly simple in principle. Hardware stores sell adapter pieces that let you connect an ordinary household tap to a camper's pipework.

With the pump, though, you do have to make sure it suits the pressure required and the tap you are using. Which connectors and adapters you need depends on the tap itself and on the pipework you have.

Do you have more questions about our water system?

Then please do write to us!


With 🐿️ by Evelyne

Written by

Evelyne Buttet

Illustrator, writer & barista

Evelyne Buttet likes African wildlife and everything that can fly or lives above the tree line.