How to Dump RV Waste Tanks: Easy (No Mess) Guide

how to dump rv waste tanks

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Dumping your RV waste tanks is not as bad as it sounds. In fact, it’s actually easy to do.

How do RV holding tanks work?

Let’s start with a quick overview of RV tanks. Most RVs have three separate holding tanks. Fresh, gray and black. In a nutshell, they hold all the liquid you use on a daily basis so that you can run water and use the toilet even when you are not connected to campground hookups.

Fresh Tank: The RV fresh tank holds clean “fresh” water. It uses a water pump to supply water to your RV faucets and shower when you are off grid. When your RV is connected to a campground water connection (aka city water) the fresh water tank is bypassed and the water runs directly from the campground spigot, through your RV water pipes to your faucets.

Grey Tank: The RV grey tank holds the water that drains from your RV sinks and shower.

Black Tank: The RV black tank holds everything that is flushed down your RV toilet.

So, you fill your fresh tank with clean water to use in your RV. And the black and grey tanks hold the liquid waste until you empty (aka dump) it. The waste tanks (black and grey) have a 3 inch outlet at the bottom that can be opened with a gate valve. When the outlet gate valve is opened, the contents flow downward, through the sewer hose and into the sewer. That’s it, a simple gravity based system.

Of course, your RV black and grey tanks need to be emptied once they are full. So, let’s get this show on the road and learn how to dump RV waste.

How To Dump Your RV waste Tanks


Your black and grey tanks need to be at least 2/3 full before you dump your RV waste.

Always wear disposable gloves when hooking up your sewer connection and emptying your RV waste tanks.

rv sewer hookup

Time Required :



What You Need:

Disposable gloves
RV sewer hose and adapter (See RV Sewer Kit and upgrade recommendations.)
Dump station or campground sewer hookup

Steps to empty your RV black and grey tanks:

1. Connect your sewer hose.

Verify that your RV sewer outlet valves are closed and remove the cover. Attach one end of your sewer hose to the outlet on your RV. Connect the other end to the dump station or campsite sewer hookup. Take care to ensure that your sewer hose is securely connected.

2. Test connections with grey water.

If you want to play it safe, test your connections by releasing a little bit of grey water. Open your grey water outlet, just for a second or two and close it again. Did the water flow through the hose and into the sewer?

3. Empty your black tank.

Open your black water outlet valve. It should be clearly labeled. The contents will flow out through your sewer hose and into the campground or dump station sewer. Once you can no longer hear the liquid draining, it should be empty. If you are using a clear sewer extender you will be able to see when the flow of waste has stopped. Always empty your black tank first and grey tank second – the grey water will rinse away any black water in your sewer hose.

4. Flush your black tank.

Now is the time to flush your black tank. We flush ours every time we empty it and recommend you do too.
Do not close the black water outlet yet.
Connect one end of your black tank flush hose to the campground or dump station water and connect the other to your black tank flush inlet. If your RV does not have a built in flushing system you can use a Rhino Blaster Sewer Rinser adapter.
Turn on the water and let it run for a while. If you have a clear sewer extender, now is when it really comes in handy. You’ll be able to see when the water runs clear.
When the tank is clean, turn off the water and disconnect your black tank flush hose.
Close your black water outlet valve using the lever.

5. Empty your grey tank.

Pull the lever that opens your grey water outlet. As the grey waste water flows out, it will wash away any leftover black tank bits that may be lurking in your sewer hose. Once the grey water has stopped flowing, close your grey tank outlet.

6. Disconnect your sewer hose.

Detach the RV side first. As you move towards the sewer connection, keep the end of the sewer hose raised so that any liquid remaining in the hose drains into the sewer. Make sure to double check that your waste outlet valves are closed and put the cap back on your RV sewer outlet. If you’re at a campground, of course you can just leave your hose hooked up until it’s time to break camp.

That’s it! Now you know how to dump your RV waste tanks! Now wash your hands:)

RV Sewer Hose Kit

This sewer hose kit will work well for dump stations and most campgrounds. It includes:

  • A 20 foot sewer hose (in two 10 foot sections) with a clear elbow, a 4 in 1 adapter and 4 storage caps.
  • Black tank flush hose. Do not use your fresh water hose.
  • Sewer supports to ensure your sewer run is angled downhill at a campground.
  • Gloves.

Check out the 5 Best RV Sewer Hoses – 2024 Buying Guide for our top sewer hose and accessory picks.

Tips and tricks to make emptying your RV waste tanks easier (and avoid a mess!)

  • Nervous about dumping your tanks? Try a practice run with grey water. Once your sewer hose is connected, empty some grey water to make sure that everything is working.
  • Never leave your black tank open at a campground. It will become hopelessly clogged. Only open it when you empty your black tank.
  • At a dump station, keep your sewer run short – it makes it easier to empty your RV tanks. Position your sewer outlet valve close to the dump station hookup.
  • Use RV toilet paper – it’s designed to break down quickly and prevent clogs in your black tank. Our top choice (and what we use) is Scott Rapid-Dissolving Toilet Paper for RVs. It’s available in the RV section at Walmart stores too.
  • clear sewer extender attachment lets you see exactly what is going on when you empty and flush your tanks.
  • Black tank treatment pods like Walex Porta-Pak Drop-Ins help eliminate odors, dissolve solids and prevent clogs. After you empty your tanks, simply drop one into your black tank and add a little bit of water.
  • When you use your RV toilet, always add a little extra water. (Unless you’re boondocking and conserving water.)
  • Use a dedicated water hose for flushing your black tank. Not your fresh water hose!
  • If a sewer run is long, empty any standing water from the hose before disconnecting it. Start at the RV end of the sewer hose and lift it so that any liquid flows towards the sewer hookup. Move towards the campground or dump station hookup while raising a section of the hose at a time until all of the liquid has flowed into the sewer.

While the idea of dumping your RV waste with a hose at a campground or dump station can sound intimidating and gross, it’s easier (and cleaner) than it sounds. Take your time and make sure to double check all of your connections. And, if in doubt, test your sewer run with grey water first.

That’s a wrap! Thanks for stopping by. We hope you enjoyed this article. See you somewhere down the road!

how to dump rv waste tanks

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