How To Build An Rv Septic System

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There are many ways to build an RV septic system, but this article will focus on a few of the most common and effective methods. Whether you’re building a new system from scratch or retrofitting your old system for use with an RV, following these tips can help ensure that your excrement gets flushed down the drain without clogging up pipes or backing up into tanks.

Basic Components of the RV Septic System

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Greywater tank –  The grey water tank holds kitchen sink and shower wastes (sinks that drain into a pipe instead of sitting in a dishpan).

Blackwater tank – The black water tank holds waste from toilets. 

Dumping system – is how the two tanks are emptied.

Grease trap – The grease trap is how larger pieces of food are caught to prevent them from entering the sewage system.

How To Build an RV Septic System

You need a few tools to build your septic system:

Ames 25332100 tempered steel round point shovel with fiberglass handle, 61-inch


Perforated corrugated expandable flexible landscape drain pipe, 4-in. By 25-ft.

Perforated PVC pipes

Zantle ratchet-type tube and pipe cutter for cutting o. D. Pex, pvc, and ppr plastic hoses and plumbing pipes up to 1-5/8" inches, ideal for home working and plumbers (orange)

PVC Pipe Cutters

Koehler enterprises ke28bx 10 piece hose clamp box (size sae 28), silver

Hose Clamps

Plasticover pcbr360200 rosin paper, 36" x 200' (600 sq. Ft. ), brown

Paper Rosin

Craftsman tape measure, self-lock, 25-foot (cmht37225s)

Tape Measure

Rectorseal 31631 1/4 pint brush top tru-blu pipe thread sealant , blue

Pipe Glue

Peipu nitrile and vinyl blend material disposable gloves (medium, 100-count), powder free, cleaning service gloves, latex free

Rubber Gloves

2 in x 1000 ft 5 mil detectable safety tape caution buried sewer line below green/black print

Sewer Tapes

8pack 4-way pvc fittings, 1" furniture grade elbow fitting for building heavy duty pvc furniture, sch 40 4-way side outlet tees, pvc conner fittings for greenhouse shed pipe fittings tent connection


Step by step guide on how to build an RV septic system

  1. Locate the RV’s main sewer line, which is typically a 2″ PVC or 3″ ABS pipe.
  2. Mark the point where you will tie into this line before connecting your new system to it.
  3. You can cut it open with a power saw and a metal blade, or a hacksaw for a more personalized touch.
  4. Once you have cut into the line, insert a 90-degree elbow fitting, followed by an end cap. Make sure all of your fittings are glued securely so no gas leaks occur from the line, as this is how septic systems catch fire. A rubber gasket between each joint helps assure that there are no gaps for air to escape through. It also helps prevent leaks down the road if anyone joint should fail due to poor construction or age.
  5. Make sure the elbow is pointing away from your system so that any gas can flow out of it. If it was facing inward, pressure could build up and cause a rupture in your new septic tank or leach field pipes.
  6. Once you have installed all of the fittings needed to hook into the RV’s mainline, turn on a nearby water faucet to test them for leaks. Fix any that occur before continuing with the construction of the septic system itself.
  7. Since you are probably building an electric pump septic system, lay down some ground cloth as thick as you would like your final grade to be over the top of where you will be installing the new tank and leach lines. You may need to purchase this at a hardware store or use something you have on hand, such as an old shower curtain.
  8. Even if your system uses a small gas-powered pump that doesn’t require electricity, putting down the ground cloth will keep fine particles out of the tank and lines to make cleaning easier in the future.
  9. Once you are finished installing all of your piping between the mainline and tank, dump some water into the container to test how fast it can flush through. This is how you will determine how large your leach field line must be. If it drains too quickly, increases its size by adding more length with 1″ irrigation tubing coiled around rocks or bricks every six feet or so.
  10. Add another 90-degree elbow fitting inside of your first one pointing downward, then direct your leach line into either a prepared gravel trench or a flexible corrugated pipe.
  11. Make sure this section of the leach line is six feet away from the septic tank’s exit point before going back to how it will attach to your final tank seal and how the pump connects through the lid of the main box.
  12. Place a check valve on all of your fittings leading directly from where they attach to PVC piping to keep sewage from backing up into them if they should clog. The type that looks like a small white triangle with an arrow inside of it is what you need for this purpose.
  13. Once everything has been hooked up, pour one gallon of water directly over each joint in turn and recheck for any leaks. Fix them before filling the tank with water to test how well your system works in general.
  14. If you have a sand-based leach field, make sure it is five feet away from any plants or other items that might be ruined by too much exposure to sewage. You may also need to purchase special sand if it isn’t included), and do not install the tank itself directly over the leach line at least 12 inches below ground level. The sand should remain clear of trees, shrubs, and other growth that could potentially suck up the liquid beneath it.
  15. Finally, add mulch around all of these areas to prevent weeds from growing into or choking them out when rain washes trash onto them from lawns above.

Additional Tips for RV Septic Management

  • As the seasons change, how often you use your RV can have a big effect on how quickly its septic system becomes overwhelmed. If you only visit for a few weeks out of the year, empty and clean your tanks as soon as possible to limit how much debris builds up inside them.
  • During the warmer months, don’t forget that mosquitoes lay eggs in standing water. Removing all of it from your tank helps keep insect populations from growing too large around your home or campsite.
  • When switching from one location to another, make sure to completely pump out any wastewater before leaving your site for extended periods of time. Shorter trips should be fine if you let the water run through the system until there is nothing left to drain out onto the open ground once it is charged back up with fresh water.
  • This will help eliminate any odors in the tank or in your RV after you turn on the system again before moving to a different location, too.
  • If possible, try to use biodegradable soaps and laundry detergent that does not contain phosphates or other additives that can build up inside of the tank over time. These are especially harmful because they kill off naturally occurring bacteria that decompose trash into useful soil nutrients. Without them, how well your septic system works may decrease over time until you have to replace the entire unit.  

Can A Camper Be Connected To A Septic Tank?

Many people who live in camper trailers want to know how this is possible.

First of all, a camper trailer does not come with a septic system. This means that there needs to be one installed before you can connect it to the sewer line. The good news is that installing an RV waste pump and the septic tank is relatively simple and straightforward. You might even decide to do it yourself!

First of all, you will need to have a hole cut into the side of your camper for a sewage connection. Make sure this is as far from the water source as possible so you don’t contaminate freshwater with sewage. Once you’ve done that, you can install an RV sewer pump. This pumps sewage from the camper right through the sewage line using electricity or battery power. You can go ahead and run a line from it directly to your septic tank.

Of course, if the camper is significantly away from your house’s sewer line, then there are other solutions to how to build an RV septic system that are available. Installing a holding tank is one way that people have recently started doing things. This is where the sewage is stored until you can get to a dump station. You can buy or rent one of these tanks to keep connected to your camper while you are at home. When it’s time to go camping, disconnect this tank and connect your sewer pump instead.

We hope this guide has been helpful in clearing up some of the confusion around how to build a septic system. If you have any other questions, don’t hesitate to reach out. And if you’re ready for us to help with your construction from start to finish, we can do that too! Let’s get started on designing and building your new RV septic system today!

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