How does RV plumbing work? The specific plumbing fitting in your RV or Camper varies depending on your model’s setup and size. Still, many have similar plumbing parts you’d find in a house plumbing system.
Here we will, very simply, break down how the shower, toilet, and sink work and what water holding tanks are connected to them.
Is RV Plumbing The Same As House Plumbing?
No, RV plumbing and house plumbing are not the same. Although some external parts, like the faucet, are the same they may connect to the plumbing system differently.
So, you may need adapters to make sure everything works correctly.
RV Holding Tank Plumbing Diagram

How Does RV Plumbing Work?
Depending on your RV’s make, model, and size, it may have a self-contained plumbing system that includes a toilet, sink, and shower.
We focus on self-contained RV plumbing with a comprehensive water system that includes a black water tank, grey water tank, and a freshwater tank (often located on the side of the Rig).
- Black Water Tanks: Flush the toilet and this is where the poop goes.
- Gray Water Tanks: Contains soap, food particles, and other contaminants
- Freshwater Tanks: Holds the clean, potable water that comes out of the RV sink, toilet, and shower.
These water tanks are under the chassis, so they aren’t connected to a city system. RV water tanks are what enable you to go off-grid for dry camping or boondocking adventures.
Related: Best RV Toilet Reviews
RV Plumbing Explained In Depth
How Do RV Bathrooms Work?
Here we quickly break down how RV bathroom plumbing works (sink, shower, and toilet)
How Do RV Showers Work?
Water is brought to your RV shower through a hose that is hooked up to a freshwater tank. The shower water is then drained into the gray water tank mentioned above.
Related: Best RV Shower Head Reviews
How Do RV Sinks Work?
RV sinks are made to work with the RV and camper plumbing systems, which utilize PVC or flexible pipelines rather than rigid metal pipes you’d find in most apartments or single 2-story homes.
As for the shower and toilet, the water used to clean your dishes or wash your hands come from a freshwater holding tank located on the exterior of your recreational vechile.
Then, the dirty water is filtered into a gray water holding tank.
How Do RV Toilets Work?
An RV toilet works primarily on gravity. To be more specific let’s break down where your toilet waste goes and how much water the toilet flushes.
Related: Cassette Toilet vs Composting Toilet
Where Does The Poop Go in an RV?
First, the poop in your RV goes into a poop tank aka the black water tank. Finally, your poop is dumped in a dump station.
A dump station is a place that was created for the safe and sanitary disposal of your RV waste or poop. That waste is disposed of in a communal septic tank through a hose (See The Best Sewer Hose For RVs and The Best RV Sewer Hose Support ).
How Much Water Does an RV Toilet Use per Flush?
Around two quarts or half a gallon of water is used per flush in an RV toilet.
Can You Drink Water From Your RV?
Yes, you can drink water from your RV. As long as the tank system is treated and clean properly, you are all set to drink from the tap water in your RV.
On that note, if you’re renting an RV, you should ask the owner the sanitary status of their clean water tanks.
If you don’t know and can’t get to the owner or previous renter, I’d buy a few gallons in the meanwhile. Your next option is to clean the tanks yourself (see the related post below). Better safe than sorry.
Related: How To Sanitize RV Water Tank
That’s How RV Plumbing Works!
This was a simple breakdown of how RV plumbing works from washing dishes to taking poops.
Safe Travels!