If you are looking for more details, kindly visit pop up camper fresh water tank.

Seriously, just spend a couple of weeks backpacking in the mountains or even in some foreign countries, and you’ll quickly develop a stronger appreciation for freshwater on-demand.

While camping, most people are going to interact with their RV’s plumbing system throughout the day, every day. Think about it. Between cooking, cleaning, and using the bathroom, the plumbing in an RV lies at the core of many daily chores.

Because of this, it is crucial to know the ins and outs of your own plumbing system and to be an informed buyer when looking to purchase an RV.

Read on to learn what to look for when inspecting an RV’s water tank situation and how to care for your own RV plumbing system so that you can avoid a really nasty mess.

RV Holding Tanks

Most RVs have three separate water holding tanks. These tanks are all part of your camper’s plumbing system and play very different roles in supporting that system. Each tank will need specific, specialized care in order to maintain proper functionality. I have already covered an article on the working of an RV holding tank sensors.

The three types of water holding tanks you’ll utilize in your RV are the fresh water tank, grey water tank, and black water tank.

Freshwater Tank

Your freshwater tank, as the name implies, holds your fresh, potable water. Potable is a term that refers to whether or not water is safe for human consumption. You’ll see that term as a label on spigots at RV campgrounds, gas stations, or anywhere that has a freshwater connection.

If a spigot is labeled non-potable, do not fill your freshwater tank with it. Non-potable water has not been filtered or processed and should not be considered safe for human consumption.

Grey Water Tank

The grey water tank holds water that has been used and is now considered spoiled. Appliances that drain into your grey water tank will be the faucets in your bathroom and galley, and if your camper has one, your shower.

Generally, grey water is a byproduct of cleaning dishes, washing food, or bathing. It is called grey water because it often will have a greyish hue to it when drained from the tank.

Black Water Tank

The black water tank is often referred to as the “septic tank” or “waste tank”. This tank holds liquid and solid waste that drains from the toilet in your RV. Only RVs with toilets have a black water tank.

Occasionally you may come across a camper that has a combination of grey and black water tank. These tanks hold all the dirty water that drains from your RV.

These tanks are called “black water” because when drained, the water is significantly darker than the grey water tank.

Holding Tank Capacity

Arguably the most important detail to know about your RV’s holding tanks is their capacity. Some regions even require the capacity of water holding tanks to be documented when registering the vehicle.

An RV often comes with a three-number label that refers to the capacity of the holding tanks. This number can be written in X-X-X format. So, for example, if you see a label saying 50-35-30, that means the fresh water tank capacity is 50 gallons, the grey water tank holds 35 gallons, and the black water tank holds 30.

You won’t always find the tank capacities labeled this way, but you’ll always be able to locate capacities somewhere on the RV or in the user manual.

Typical Capacities

Average holding tank sizes are tricky to pin down, as they can vary significantly from each manufacturer.

Typically though, you can expect an RV’s fresh water tank to hold anywhere from 20-100 gallons of water. A large Class-A RV rarely comes with a freshwater tank smaller than 60 gallons. Class-C RVs hold anywhere from 35-60 gallons while a class-B RV and campers like this adventure camper range from 20-40 gallons.

Note: Don’t be confused by the letters associated with RV sizes. From largest to smallest, it goes class-A, class-C, class-B+, class-B. Weird, I know.

What Size Tanks Do You Need?

So, how big are RV water tanks? A common size of RV freshwater tank is 40 gallons, and so people often inquire as to how long a 40-gallon tank will last them. This will vary wildly from person to person, as will require holding tank capacities. Here are some factors that will play into the size of tanks needed:

• How much water is used for cleaning and bathing
• Amount of people camping/living out of the RV
• How many days were spent boondocking vs days spent in a campground with a water hookup
• How much water is consumed for hydration
• Amount of water used for cooking

Spend some time thinking critically about these factors. It is crucial to have the proper RV holding tank size so you don’t have to make cumbersome trips into town to dump stations, and so that you never run out of fresh water for drinking. Running out of fresh water is scary and can be life-threatening. Please never drive into the remote wilderness without ensuring you have an abundance of fresh water.

Importance of Fresh Water While Camping

When I was around 20 years old, I took my first solo road trip around the west half of the United States. While gearing up for this epic adventure (it was seriously so epic), I picked myself up two 5-gallon water jugs. These jugs were super tough, BPA-free, and most importantly, held more than enough water for my daily needs and an emergency reserve.

With that said, 10 gallons is not a ton of water. I wanted bigger containers, but I was limited by space in my truck and ended up having to refill every week which was a hassle. Even so, when those puppies were full, I knew I could confidently drive into the desert by myself and have plenty of water to thrive.

When adventuring in your camper, you’ll need enough fresh water to perform all daily chores and keep yourself hydrated while also having an emergency reserve. Because of this, you’ll want to pay particular attention to the size of your freshwater holding tank and determine if it will meet all your demands.

Tips on Filling Your Freshwater Tank

Use these tips to make filling your fresh water tank a seamless, safe, and hassle-free task.

Potable Water Hose

Buy and utilize a potable water hose. A potable water hose is a hose you will use solely for the purpose of filling your fresh water tank. They are typically white in color and are made of a material that doesn’t leave a synthetic taste in the water.

Use Safe Spigots

Only fill using spigots that are labeled “potable” or “drinkable”. Even if it takes a long time to find a spigot offering drinkable water, never compromise and fill with unknown water. This is especially pertinent if you are traveling in a country that has questionable city tap water.

Use Separate Hoses

Never use the black water drain hose for filling your fresh water tank. Doing this could be exceptionally harmful to your health and would quite frankly be really gross.

While I think this would be difficult to do in the first place because the hoses are very different sizes, I think it is still worth saying. Be safe with drinking water.

Water Treatment Tablets

Similar to what backpackers use to purify water in the backcountry, some companies offer water treatment tablets that you can put into your freshwater tank to help purify the water and prevent the growth of bacteria in your tank. The best tablets for this process are made with chlorine dioxide, a chemical that is safe for human consumption in small concentrations.

If you choose to use treatment tablets in your tanks, please do extensive research on the tablet you choose, and be careful with how much you use.

How to Measure Water Holding Tank Capacity

Sometimes, for whatever reason, it is difficult to pin down the exact capacity of your camper’s holding tanks by inspecting the RV. If you find yourself in this position, there are ways to measure how many gallons each of your tanks hold.

Internet Research

The first route you should take is to simply hop on the internet and look up your RV’s make and model. You should be able to find the dimensions and capacity of your holding tanks on the manufacturer’s website.

Calculating Yourself

If internet research yields no results, you’ll have to try a slightly more engaged process. Find where each tank lives in your camper and using a tape measure, measure the height, width, and length of each tank. Use those values to find the total volume in cubic feet or inches (or centimeters if you roll like that).

Then hop back online and use a converting software to convert the cubic volume into total gallons. Boom, there’s your holding capacity.

If you don’t have physical access to your RV holding tanks and absolutely need to know the dimensions, you can pay an RV technician to do this process for you. A technician will have the tools and know how to safely access the tanks and grab dimensions for you.

Draining Waste Tanks

The not-so-glamorous side of owning and traveling in a camper. This chore is not even remotely fun, but with practice can be a quick, simple process.

Black Tank

After finding a dumping station, position your RV’s drain valve near the dumping port. Connect your wastewater hose to your RV and to the dumping port and open your black tank’s valve. You should hear or potentially even see your black tank draining into the dump station’s tank.

Grey Tank

You should try to always drain your grey water tank after draining the septic tank. This is for the simple purpose of allowing the flow of grey water to clean out human waste from inside your hose after draining the black water tank. The process follows essentially the same steps as draining the black tank.

Free Flowing Grey Water

While boondocking, some people choose to leave their grey water tank open and let it drain onto the ground as they produce it. This can be done safely without hurting the environment by using biodegradable soaps for every single cleaning process.

This means you need to use a biodegradable soap for washing hands, dishes, body, hair, and everything. If you choose not to use biodegradable soap, you will be releasing synthetic chemicals into the environment and hurting the natural habitat for flora and fauna. Please don’t do this.

I suggest playing it safe and waiting to dump at a real dump station.

Conserving Water

Practice conserving water to reduce the frequency at which you have to refill your fresh water, and dump your wastewater.

Military Style Shower

The average American shower is 8 minutes long and uses just over 17 gallons of water. If you use this much water every time you use your RV shower, you’ll have to constantly be refilling your fresh tank, a tedious and time-consuming task.

Follow these steps to take a water-conserving style shower often referred to as a military-style shower:

1. Remove clothes and step into the shower before turning on the water
2. Turn on the water and quickly wet your entire body and hair, turning it off once fully wet
3. Lather your body with soap and your hair with shampoo
4. Turn the water back on and rinse quickly and effectively
5. Turn off the water as soon as all soap is rinsed

This may not be the warmest or most pleasant shower you’ll ever take, but it will save you a heck of a lot of water.

Efficient Dishwashing

Washing dishes is another task that typically consumes a lot of fresh water. Try adopting the military style shower technique for washing dishes in order to preserve your fresh water.

Pro-tip: Dr. Bronner’s is a great, all-natural castile soap that smells great and is biodegradable. They are not affiliated with this blog in any way; I just seriously love their soap. Check ’em out.

Hydration

Please don’t conserve water by not hydrating properly. Hydrating is so important to health, and you can end up in dangerous situations if you are not drinking enough water every day.

This is particularly true in deserts; a popular boondocking environment amongst RVers.

Winterizing

Winterizing refers to the process of preparing your RV for less or no use over the winter months. This is a vital process to do every autumn if you wish to protect the investment in your camper. Without proper winterization, you run the risk of damaging most, if not all of your plumbing system as water expands while freezing.

This expansion can cause pipes to burst which then can result in mold or rot damage if an unnoticed, burst-pipe leaks into your walls, floors, and cabinets. Freezing water can also crack components in your water pump, water heater, and faucets, leading to costly repairs.

The people over at Fraserway RV wrote a great article detailing how to fully winterize your RV. Give it a read to learn what steps to take to winterize your own plumbing system.

Conclusion

If you are looking to buy an RV, use your newly learned information to make an informed decision before you purchase. If you already own a camper, I hope this article has helped you to learn a bit more about your holding tank system and how to care for it.

Happy camping!

Guide To RV Holding Tank Sizes

By Kelly Beasley

Is the size of your RV holding tanks essential to know? It most definitely is if you ever decide to camp without hookups.

The odds you will camp without campground hookups sometimes are pretty high. So yes, you should be aware of your RV waste tank sizes. This is the MOST important to know BEFORE you buy an RV.

Why? Because if you are a camper who wants to dry camp a lot, you might regret buying a camper trailer with, say, a 10-gallon freshwater tank.

That RV is also not likely to have a large grey water tank or black water tank.

Therefore, your stay length is, for the most part, limited by your RV tank size. Sure, you can dump your waste tanks using a portable RV tank, but it's another chore to do while camping.

Best to have tank capacity that can accommodate your camping duration needs.

What Is The Average Size RV Waste Tank?

There is no one-size-fits-all when it comes to a typical RV holding tank size. They all vary.

You can probably figure out on your own that, on average, smaller trailers and motorhomes typically have smaller capacities.

Likewise, larger RVs tend to have larger RV waste tank and freshwater tank capacities.

Are there average sizes? Not really. Their capacities can vary wildly.

What Are RV Holding Tanks?

All RVs commonly come with these three RV sewer holding tanks:

• Fresh water tank

• Black water tank

• Gray water tank

Here's a quick rundown of the purpose of each of these three tanks:

Fresh Water Tank

The fresh water tank holds the fresh/clean water you use for showering, washing dishes, and for when you flush the toilet. RV fresh water pumps push the freshwater through your pipes.

Contact us to discuss your requirements of caravan camper trailer. Our experienced sales team can help you identify the options that best suit your needs.

Black Water Tank

Camper black water tanks hold everything (liquid and solid waste) that goes down the toilet. It's the keeper of sewage/human waste.

How many gallons is a black tank? As many as the RV tells you it holds. RV black water tank size varies from RV to RV. The average RV black water tank size can vary from as little as 15 gallons to 60+ gallons. The larger the RV, typically the larger the RV black tank size.

Gray Water Tank

A gray water storage tank holds the waste water that goes down your sink and shower drains.

The RV black water tanks and gray tanks are made to hold all of your wastewater until you can get your RV to a dump station to dump your black and grey tanks. Emptying them is relatively easy.

The fresh water tank is the one that supplies the water that will end up in the two waste tanks.

What Is The Typical RV Holding Tank Size?

What size are RV holding tanks? Is there a typical RV holding tank size?

Though there may be an 'average' size for holding tanks on certain RV classes, you should not assume the tank capacity of any of your tanks or ANY RV you are looking to purchase.

There are no 'average' sizes of the three tanks. Remember, there are usually three different tanks!

And they rarely are the same size. Every RV has its own configuration, some requiring X gallons of water for drinking and washing, and others having a black water capacity that can suit a family of four.

Typically, the larger the RV, the larger the tanks will be. A smaller travel trailer will have, USUALLY, less tank capacities than a 40' Class A RV.

The smallest of RV classes, the Class B RV (van), typically has the smallest tanks. The 'Class A' motorhome tends to have the largest sized tanks.

Sometimes RVs even have two black water tanks or grey water tanks.

Suppose you are ever camping without connections to water and a sewer. In that case, it's best to have a general idea of your RV water tank size and its waste tank sizes and know how long you can go without having to dump (draining your waste using a camper septic hose) or refill.

Also, take into consideration how many people will be staying in the RV. The more users, the shorter your RV water tanks and waste tanks will last.

Where Do I Look For RV Tank Sizes?

You might find the size of your black water holding tank and grey water tanks inside the RV. It might be on a piece of paper attached to the inside of a cabinet somewhere.

This paper also might tell you other details about the appliances in the RV, such as your refrigerator, stove, and furnace.

If not there, check your owner's manual.

If your RV came without an owner's manual, go online and look it up there.

Simply Google search your RV brand, make, model, and year and 'tank sizes.'

You may be able to find the brochure for your year and model RV which should indicate the RV tank capacities.

How Do I Read The Three Tank Size Numbers?

The gallon capacities of the three tanks might be written something like this in your RV:

40-35-28 => Fresh-Grey-Black

So you have a 40-gallon fresh tank, 35-gallon capacity grey tank, and a 28-gallon capacity black tank.

The order of these is always the same. So try to remember from left to right, the same way you write. Starts clean and ends up dirty!

Clean on left, dirty on the right, beginning to end.

What Size RV Holding Tank Do I Need?

Keep in mind that almost every RV has THREE holding tanks - One to hold fresh water, one that holds toilet sewage, and one that catches drain water.

How much cooking you do, how much water you use, how many people are using the RV... these are all factors to consider when figuring out how large your tanks should be.

It's entirely possible for a family of four to make it a week on all three tanks IF THEY ARE CONSERVATIVE, minimize their water usage, and don't have small tanks to start with.

Also, there are ways to dump the waste and refill the fresh water without moving the RV.

But if you have to do so every three days or so, this is a great way to make a relaxing vacation not so relaxing.

The larger your tanks, the better. Especially if you are RVing with more than two people.

How Large Is An RV Water Tank?

RV fresh water tank size range anywhere from 20 gallons to 100 gallons. A smaller RV will (typically) have a smaller freshwater tank.

Larger RVs tend to have a larger tank size for fresh water, but this isn't always the case. If you are purchasing an RV, DO NOT assume tank size based on size of the actual RV. You might be shocked to find that the relatively large recreational vehicle you are looking at has a relatively small tank capacity.

Find out if it has larger holding tanks or smaller holding tanks. If you NEVER dry camp, the average size of your tanks doesn't matter.

How Big Of A Grey Water Tank Do I Need?

Again, how large of a grey water tank you need depends on how often you want to dry camp. It also depends on how long you want to stay at that spot.

Most boondocking and dry camping spots have a stay limit, usually on average, of two weeks. Therefore, you don't need any tanks that can go longer than that.

But honestly, if you want to dry camp a lot then RV grey water tank size becomes important - the larger the tank, the better. SOME RVs come with two gray water tanks. Much more capacity there.

How Long Does It Take To Fill Up A Black Water Tank?

First of all, know that you should never leave the black tank valve open if you are connected to a sewer. This will undoubtedly cause an eventual clog via the infamous poop pyramid.

Leave it closed until almost full (might take a week or more), then open the valve to dump (when at an appropriate dump facility). Immediately close the valve again until full.

Otherwise, if you are NOT connected to a sewer via a sewer hose, how long it will take to fill is dependent on a few variables, such as:

• RV black water tank capacity.

• How many people are using the toilet?

• If you are flushing 

  TP

  down into the toilet (this takes up more space in the black tank).

• If the males are peeing into the toilet or outside.

• How much water you put into the bowl before flushing.

• How long you flush the toilet.

  
  

You could do very long flushes and fill up the toilet in a few days. Or you could be very conservative; guys pee outside, no TP down into the tank, and go for a few weeks (if your RV black tank capacity is large enough).

It all depends. It's best to experiment with this while parked at a campground with a sewer connection.

To experiment, use the toilet as you would while dry camping, and figure out how many days until your sensors read full. Then you can dump, do it a few more times, and take the average. And there's your answer.

I can go just over two weeks with how conservative I am with my toilet usage. My tank is about 27 gallons. My fresh water tank size is 20 gallons. I can also go two weeks with extreme conservative usage.

Marshall has a 45 gallon black tank (all his tanks are 45 gallons) and can go close to a month if he pees a lot outside.

How Long Can A Gray Water Tank Last?

Well, say you have and want to use a washing machine while dry camping, and have a big family that uses a ton of water.

Don't expect to go more than a few days, no matter how big your gray tank is.

My gray water tank storage capacity is pretty tiny - about 27 gallons, and I can easily go for two weeks without having to dump.

It's all about your decision of how much to conserve or not to conserve.

If you can't go as long as you want to stay, if there's a dump station nearby, OR you have the capability to lift an extremely heavy portable waste tank into the back of your pickup truck, you could empty at least part of the tank using a waste hose and rubber gloves.

Then you can go dump it without having to move the RV.

How Do You Know How Full Your Tanks Are?

Sensors make it very easy to see how full your RV tanks are. Most RVs come with built-in sensors that gauge your levels for you. Simply press a button, and the RV tank level indicator tells you how close to full or empty the tank is.

Some people can visually see their freshwater tank and see how full it is, most often in travel trailers.

Others can look right down into their black tank when they flush and see how full the tank is becoming.

Your RV toilet tells you when the black tank is about to be full to the brim. It will 'burp'... something you will quickly learn by ear.

When it does the burp, you only have a few flushes left before the black water tank backs up into the toilet bowl.

The gray tank, once full, will start to back up into the lowest outlet of the plumbing systems, usually the shower drain.

You don't have to let them go this long before you know you're full. Your sensors, if working correctly, will monitor and let you know your waste tanks are about to be full or empty (fresh water)!

Once they are, it's time to look for dump stations in the area.

Conclusion

Your RV comes with three tanks. A gray water tank, a black water tank, and a fresh water tank for drinking water and for cleaning dishes and bodies.

They rarely all have the same size capacity. Some have larger tanks, while others have smaller tanks.

Usually, the fresh water tank is larger than the other two tanks. Smaller campers have smaller tanks, while the RV holding tank capacity of a larger RV will typically be higher.

To find out the size of yours, check the owner's manual, or look it up online. Sometimes the sizes are displayed on an information sheet attached to the inside the RV somewhere.

How large of these tanks you need depends on many things - how well do you conserve water? Are you willing to take navy showers? And will you be connected to a sewer system most of the time? Will you have a water hookup?

If you want to dry camp at all, be aware of the sizes of your black and gray water tanks. If you are buying an RV, DO NOT OVERLOOK the holding tank size of any RV you are interested in.

The more tank capacity you have, the better! It can't hurt, right?

How many gallons does an RV hold? As mentioned above, it depends on the size of the tank, which can vary considerably between makes, models, and floor plans.

Author: Kelly Beasley

I dedicated myself to living the full-time RV life for over 6.5 years, immersing myself in the unique quirks and joys of the boondocking lifestyle and gaining a wealth of knowledge and experience along the way. In December 2020, my business partner and I made the transition to part-time RVing, but in January 2023, we hit the road once again, this time in our trusty vans. My mission is to help others embrace the RVing lifestyle with confidence and excitement, armed with the knowledge and resources needed to make the most of their adventures. I believe that the more you know, the more you can truly appreciate and enjoy the freedom and flexibility of the open road.

Are you interested in learning more about base camp for sale? Contact us today to secure an expert consultation!