Why Does My Camper Smell Like Sewage? (5 CAUSES & Remedy)

Why Does Camper Smells Like Sewage

Published Date: March 5, 2021

Last Updated on June 22, 2023 by Camper Front

When RVing with your friends and family, the last thing you want is a smelly RV that will spoil the fun. But why does the camper smells like sewage?

Basically, there are many things that can lead to a stinky RV, such as a dirty toilet, a clogged black tank, etc. and we’re going to discuss all that today.

Whether you’re a weekend warrior or you camp full-time, you’ve probably dealt with holding tank odors at some point.

So, if your camper trailer smells like sewage, you’re not alone. Lots of RVers have faced similar problems at some point, and the good thing is that there’s a solution to it.

In this article, we will look at the common causes of sewage smells in RVs and some of the most effective ways to get rid of stinky odor in your camper.

But before we start, you need to understand how RV toilets work!

How RV Toilet Systems Work

There are basically three holding tanks in RVs. One is for the freshwater tank that is used for showering and drinking, the second one is for the gray water tank (water that comes from washing dishes or showering), and the third is the black water tank for waste.

Also, the gray water tank helps in keeping the waste thoroughly mixed with liquid, preventing it from drying out. The liquid stays in the tank when the sewer line is closed, keeping the waste wet and decomposing.

But if the sewer line is left open, the fluids will pass out and the waste will get dried. This will make it tougher to clean the holding tank and keep it running properly.

RV toilets need water from the gray water tank because they do not use lots of water in their flush.

Camper trailer toilets are similar to airplane toilets, unlike the toilets in a home. All that needs to be flushed is gravity and a small amount of water.

Interestingly, there will be a spray nozzle nearby in some campers to rinse down any remaining waste. You can also fill the tank with more water if it’s required to flush out the black water properly.

Because of this, it is important not to flush certain things down an RV toilet. Flushing these things could create a clog or a lack of decomposition in the black water tank, leading to sewer smells.

Caution: Avoid flushing feminine products, paper towels, or toilet paper that is not specified for septic tanks.

Why Does My Camper Smell Like Sewage?

How RV Toilet Systems Work

Several reasons can make a camper smell like sewage. Good enough, you can easily fix most of these yourself. Although some problems will definitely require the help of a professional.

So, exactly why does the camper smell like sewage?

Below are some of the known reasons:

1. Clogged Black Tank

One of the most common problems is a clogged black tank, and this one is usually somewhat tricky to deal with.

Basically, a clogged tank won’t dump completely (or at all sometimes), which means that you’re unknowingly left with old sewage stuck in your holding tank for a long time which can lead to your camper smelling like sewage.

Of cause, this smell won’t stop anytime soon if you do nothing about it. So, you’ll have to address the clog as soon as possible.

A clog is usually caused by flushing too much toilet paper with insufficient water. This can, sometimes, also mean that you’re not flushing the toilet long enough.

And other times, it happens because you left the dump valve open, allowing every liquid to pass through the tank while leaving only the solid waste behind.

This issue can also be caused by a leaky black tank as well as by flushing something that should not have been flushed.

2. Dirty Toilet

This is basically the easiest problem to fix in a smelly camper. RV toilets, especially the plastic types, will sometimes hold onto smells.

And if you wait longer to get the toilet cleaned, it will hold unto more stink until the sewage smell eventually fills the entire camper.

The good thing, however, is that this issue is incredibly easy to tackle. You can simply use your favorite household bathroom cleaner to clean and get rid of the smell.

Just ensure you clean every nook and cranny of the toilet and the sewage smell will be gone.

3. Tank Buildup

An RV toilet can also smell due to buildup in the black holding tank. This might be just a buildup along the walls of the tank that comes from constant use or a huge buildup of solid wastes on the bottom of the tank.

Just like clogs, solid waste buildups usually come as a result of too many solids and insufficient water in the tank. You can avoid this by simply ensuring your dump valve is closed, preventing your tank from leaking, and using enough water when flushing the toilet.

Sadly, you cannot entirely avoid buildup on the walls and bottom of the tank. Instead, you must regularly clean the walls in order to avoid a sewage smell.

4. Bowl Seal or Bad Toilet Flange

It’s also possible that your camper toilet needs a bowl seal or a new flange. These seals can both get worn out over time and can result in bad RV toilet smells.

You will know that you probably have a bad seal if your toilet bowl won’t hold water. This will also let the stinky black tank smells into the camper.

Aside from that, a leak around the bottom of the travel trailer toilet would point to a worn gasket that could be allowing smells in.

5. Clogged Vent Pipe

Apart from a clogged tank, a clog in the vent pipe can also cause a sewage RV smell.

Typically, there is a pipe from the black tank to the roof of every camper trailer, letting methane gases pass through.

If for any reason, this vent gets clogged, those gases won’t be able to pass through the roof, and will rather come up out of the toilet when it’s flushed – and certainly, this does not smell nice at all.

The easiest way to check a vent pipe for clogs and remove anything that could be blocking the airflow, connect a garden hose to the top of the pipe from the black tank and run some water through it.

How To Get Rid of Sewage Smell In a Camper

How To Get Rid of Sewage Smell In a Camper

Having discussed some of the possible reasons why a camper might smell like sewage, let’s now look at the various ways to get rid of this smell and get your RV smelling awesome once again.

1. Clean Your RV Toilet

Giving your RV toilet a good clean is one of the best and easiest ways to get rid of sewage smell or any other type of smell coming out from the toilet.

The first step towards diagnosing the odor is to check for clogs, damages, and leaks. And if it’s not any of those issues, the next thing should be to clean your camper toilet and black water tank.

You should actually make it a regular habit to clean the toilet to prevent the black water tank from getting clogged and to ensure things are running smoothly.

This should include cleaning the toilet, black water tank, sewer line, and toilet flapper, and ensuring you’re maintaining them properly.

2. Unclog Your RV Toilet

Below are the 3 ways you can unclog your RV toilet:

The first option is to open your RV toilet valve and pour some pots of hot water into the toilet. Leave the water in the tank and soak it overnight.

You can be driving around as that can help mix it all in, letting the clog loosen and easily flush through.

The second method of unclogging an RV toilet is to put ice into a full toilet of water. You want to fill the water part way only before adding the ice after which you should then add the rest of the water.

Now, flush the toilet and drive around for some time. That will allow the ice to effortlessly push the clog through. The clog will be cleared after a few flushes.

The third method is to use de-clogging chemicals. These chemicals come in different types and anyone that is specifically meant for RV toilets will undoubtedly work.

3. Check For Leaks or Damages

Check if there is damage to the tank, toilet, or sewage line. And if you found one, that part of the system may need replacement or you can call a professional to examine it and see if they can fix it.

If you notice a break or leak anywhere in the tank, especially in the black water tank, we recommend taking it to a dealer to get a quote.

Most RV users often think that the tank should be replaced whenever something small such as a leak occurs, but that is not always required.

It’s also worth noting that replacing the whole tank can cost anywhere from $300 to $800 and you’ll have to be without your camper for a while.

While checking for leaks, you should also investigate and see whether the toilet flap is secure. If it’s not snug and fits very well when closed. If the flap is loose, methane gas can leak out and let a foul smell pass through.

Therefore, if there is a leak or damage in the black water tank, toilet, or sewer line, the best first step is to consult with a professional that can fix it.

4. Unclog RV Sink

If any of the steps above didn’t solve the issue, check your gray water tank, starting from the kitchen downpipe. To do this, place a catch pan under the p-trap and under the sink, and then remove the p-trap.

Check if the water drains – and if so, it means there is no clog in this section. But if it doesn’t drain, use a sturdy wire or tweezers to clear out the drain properly.

You also want to check the p-trap for standing water. And if you notice any, clear out the clog using chemicals.

Again, check the drain for standing water starting from the end of the p-trap to the gray water tank. If you notice any, you can also use chemicals to clear out the clog or snake the drain.

Caution: Avoid using CO2 capsules, high-pressure water, or high-pressure air through the system as this could rupture the joints or pipes.

5. Unclog RV Shower Drain

The first thing you should do here is to check if the gray water tank is full. If it is full, empty it as it’s possible that the clog was just as a result of water that has nowhere to go.

Use a sink plunger to plunge the shower with sitting water in it. If after several attempts, water refuses to drain, try any of the methods below.

Get an enzyme-based drain opener specified for RV and pour it down the drain. Allow it to sit overnight in the drain so it’ll have enough time to dissolve the clog. The next morning, run hot water down the drain and plunge the shower drain if there are still clogs left.

You don’t have to buy a chemical drain opener. You can make your own with 1 cup of white vinegar and 1 cup of baking soda. Then, follow the directions above.

Use a flashlight to look down the drain and see if you can notice the offending clog. And if you can see any object or hairball causing the clog, use a coat hanger wire to remove it.

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The last thing you want to experience is a smelly camper, regardless of what’s causing the smell. Therefore, if your camper smells like sewage, the first thing is to try and identify the reason for the smell.

If you go through this guide religiously, you should be able to spot what’s causing the problem. Then, follow the steps above to tackle it and get your RV smelling nice again.

Do not hesitate to get the help of a professional if the need arises.

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