Camper Van Water Tanks (A Beginner’s Guide)

Storing water in a camper van is a critical ability that allows you to hydrate, prepare meals, clean up afterward, shower, and more. This is accomplished by installing water tanks in the camper van. However, there is a diverse range of water tanks that you can choose from, and each type has its pros and cons.

Some water tanks are permanently installed, while others can be easily removed and filled at a local tap. In our camper van, we use removable water containers, making filling our fresh water tank and dumping our grey tank a simple procedure.

In this post, we review the different types of camper van water tanks and provide intuitive diagrams with detailed component recommendations that illustrate how to install these tanks into your van’s water system.

If you’re ready, let’s dive into it.

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Removable Water Tanks

Portable water containers are the most popular freshwater storage option for budget camper van builds. The biggest reasons for their popularity are:

• Cost Effective: Cheaper than standard RV water tanks.
• Space efficient: Rectangular design fits conveniently under the sink.
• Easy to remove: With the right accessories, tanks can be disconnected & removed.

Why use the Reliance-brand water tank? We specifically recommend the Reliance ‘Aqua-Tainer’ because the cap design has a threaded spigot hole (see below image). We use this threaded hole to connect the rest of the plumbing components.

Installation Diagram

In the two pictures below, you can see how we connected the water container cap to red PEX pipe. This pipe acts as a straw to draw water from the bottom of the tank.

Materials List

Below are the materials you would need to set up the portable water tank so that it can be integrated with the rest of your water system.

Read our sink installation post for complete installation guidance (with a materials list) for this specific container.

Fixed Water Tanks

Fixed water tanks are designed for camper vans and RVs and can store anywhere between 5-50 gallons of water. Depending on the model, these tanks can be installed either inside the vehicle or outside, under the chassis.

Fixed Water Tank Anatomy

Fixed water tanks are more complicated to install than simple water containers. Below are the four ports to know when installing a fixed water tank.

• Inlet port: Where fresh water enters.
• Air vent port: Where air enters & exits.
• Outlet port: Where fresh water exits.
• Drain port: To drain and empty the water tank.

Popular Fixed Tank Sizes

Below are several of the most popular sizes for fixed water tanks. All our recommendations below are ‘spouted’ water tanks, which we recommend to make installation easier.

How much water do you need? We list our water usage rates below to help you decide what size water tank you need.

• Food Prep and Cleanup: 1.5-2 gallons per day
• Shower: 3-4 gallons per person
• Drinking Water: 1/4 gallon per person per day

The larger the water tank, the longer you can go without needing to fill up again. But in general, we recommend getting a 20-gallon tank, which should allow you to travel 4-6 days in between refills.

Installation Diagram

Below is an intuitive diagram to help you install a fixed tank in a camper van. We detail two ways to fill the tank with fresh water (fill tube or water inlet dish). It is up to you to decide which method you prefer.

Materials List

Below are all the materials you need to complete the fixed tank set up. Each tank has four ports, so we divide the materials list into four parts.

1. Water Inlet
2. Air Vent
3. Water Outlet
4. Drain

1. Water Inlet

You can choose one of two methods to fill your fixed water tank, either with a fill tube and plug or with a fixed water inlet dish.

Option 1: Plug + Filler Tube

Option 2: Inlet Dish

2. Air Vent Port

3. Outlet Port

4. Drain Port

Read our shower installation post for more detailed installation guidance (with a materials list) for fixed water tanks.

Undermount vs. Interior Water Tanks

Another benefit of these fixed water tanks is that they can be installed inside or outside under the vehicle’s chassis.

Installing a water tank under the vehicle is more complicated but frees up valuable interior space for other purposes. But one of the downsides of an under-mount installation is that, depending on the outside temperature, you may not be able to use these tanks in sub-freezing temperatures.

Good to know: Under-body water tanks are also slightly different in shape, so make sure you’re buying the correct tank type for your desired location.

Specialty Water Tanks

For maximum space efficiency, NW Conversions sells fixed water tanks that are specially designed to fit over the wheel well of most commercial vehicles, including Sprinter, Transit, and Promaster vans.

Standard 5-Gallon Water Bottles

For the most convenient, headache-free fresh water storage solution, purchasing a 5-gallon water bottle is the way to go. This is for three reasons:

1. Exchangeable: If you buy your 5-gallon bottle at a grocery store, you can exchange the empty bottle for a full one. You won’t have to pay for the plastic bottle again, just for the water.
2. Easily Refillable: You can find water refill stations using Google Maps and the iOverlander app. Sometimes, there are refill kiosks outside grocery stores.
3. Minimal Plumbing: Attach a small pump to the mouth of the water tank for virtually no plumbing.

We recommend pairing this type of water tank with an electric water pump.

Jerry Cans

Jerry cans are a type of portable water container but are taller and more narrow in design. We use this Reliance-branded tank because it comes with a funnel, allowing for a simple connection with the Camco sink drain.

Installation Guide

Below is an installation diagram for how to integrate a greywater jerry can into the sink.

Materials List

For more detailed installation guidance (with a materials list) for this specific container, read our sink installation post.

Standard Black Water Tanks

These camper van tanks collect wastewater primarily from the toilet and shower. And unlike standard grey water tanks, black water must be disposed of in designated dump stations. Black water tanks are typically installed outside, under the chassis of the camper van.

Good To Know: Installing a black water tank is tricky. You will need to drill through the van’s floor to connect the toilet & tank. You will also need to drill your own black water inlet port and air vent.

Our recommendation is to skip the black tank since they require you dump at designated RV dump stations. We don’t have a toilet in our camper van and never needed one.

Gatorade Bottles (Urine Only)

No joke, plastic bottles are a popular camper van solution for storing pee. They’re space efficient, can be emptied in any public toilet, and easy to clean. We’ve been using empty bottles for the past 4 years and have been perfectly fine with it.

We recommend Gatorade (and Vitamin Water) bottles for their bigger spout openings. We’d prefer not to get into the specifics here, but trust us when we say that the larger opening is more helpful.

For women, a Gatorade bottle works best with a female urination device (aka ‘pee funnel’). It takes some time to get used to, but Yuko swears by it.

How To Clean a Camper Van Water Tank

Once every 3-4 months, we sanitize our fresh water tanks (fixed tank & jerry can) by flushing chlorine solution through our water tanks, pipes, and pump.

1. Prepare a chlorine solution by mixing ¼ cup of household, unscented bleach with one gallon of water.
2. You will need one gallon of this chlorine solution for each 15 gallons of tank capacity.
3. Never pour pure bleach directly into your water tanks.
4. Pour the diluted chlorine solution into your water tank and fill the remaining capacity with water.
5. Turn on the water pump and allow the chlorine solution to sit in the pipes.
6. Allow the solution to sit in the water tank and pipes for 3 hours.
7. After 3 hours, drain and flush with fresh water.

Conclusion: Get The Best Water Tank For Your Unique Needs

When building a camper van, selecting the right water tank that meets your camper van needs is critical.

But there is no ‘best’ water tank.

When planning what type of tank to purchase, we recommend thinking about how you plan to use your camper van.

• How long do you plan to travel for?
• Do you plan to boondock? For how many days?
• Will you have a built-in shower?
• How important is it to remove your water tanks to refill?
• What is your budget?

Once you build around your selected water tank, it can be difficult to go back later and change the configuration. So it’s a good idea to plan ahead and design your water storage solution in advance.

Happy building!