Friday, July 1, 2022


Easy tip for draining fresh water tank: Add a hose end!

Here’s an easy tip for draining the fresh water tank: Add a hose end!

As full-time RVers staying in different RV parks across the country, we have wondered where to dump fresh water when it is not so fresh and the system needs sanitizing.

Where to drain all that water?

The RV park does not want us to drain 90 gallons (or even 20 gallons!) of water at the campsite. Although I will admit that I have resorted to stealth-opening the fresh water drain in the middle of a torrential downpour before we figured out this system…

Add a hose end

A couple of years ago, we added a hose end to the drainpipe to attach a hose to the drain and move the water off to a well-deserving tree or to the sewer. It worked okay, although after we installed it we realized that pipe threads are definitely different than hose threads and it was tough to get the hose on.

Too low

When a technician was replacing our water drain valve, he mentioned that the drain pipe was now too long with our extension and was in danger of hitting something in the road. That could rip out the whole drain pipe and put a hole in the fresh water tank. Not good…  very not good.

Easy fix

Did we want him to fix it? YES! He cut the drain pipe down a bit and added an elbow with a garden hose end. A real hose end at an angle—easy to attach a garden hose.

Easy drain

Now we can easily attach a hose (our flush hose—not the white drinking water hose) and drain the water off to a better place or put the end of the flush hose in the sewer pipe outlet. Hint: If you’re using the sewer pipe method, rinse and sanitize the hose well. It is not just fresh water that goes down the sewer pipe…

Fresh water drain with hose end
New water hose adapter under wet bay.



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1 month ago

We have a 20 gallon fresh tank on our small travel trailer, and the suggestions to just pump it into the gray tank by turning on the tap, etc. does not work, Due to the location of the intake hose for the pump, we can really only remove about 16 gallons.
We added an extension to the drain, so it reaches the side of the trailer. We can hook a garden hose to it. We also have used a pump that goes on the cordless drill, so can empty it quickly if we want, when we’re sanitizing or rinsing the system.

Rebecca Whitney
1 month ago

I have been mulling over what to do to make draining tank easier. Mine is behind the tandem axles. So I might extend the drain to a handy &safe spot near the edge of trailer where I can reach it without crawling under the trailer.
Thank you for sharing your alteration !

Phil & Peggy
1 month ago

I don’t understand the need to dump the FW tank at all. The only water in mine was put there through my RO system and filters so, no matter the original source, it’s always clean, pure, and never needs dumping. Like the commenter below said, pumping from your always clean FW tank, you always have the same good pressure and flow. Of course, if you’re not a full-timer, different story.

Jon Meyer
1 month ago

I have waited until I leave the park and open the drain valve. It empties going down the road – FRESH water only. the little bit spread per mile is negligible.

1 month ago

Good idea! Might be better than using a “Water Thief” as I have been using when draining my fresh water tank.

1 month ago

Instead of messing with another hose, I would just have both of us take some long, luxurious showers. Fresh tank will be empty fast!

1 month ago

I agree with watering trees & area plants. But RV parks don’t really want you to do it, however doing that at home is a better way for me. Not sure your new 90 degree fitting is any better than before, as you didn’t show pics of before & after, it still looks dangerously TOO close to close to the ground.

1 month ago

Put a blind cap on that hose fitting under your coach to keep it clean.

1 month ago

I did the same but for a different reason. Took forever to fill the fresh water through the Nautilus panel so now I can bottom fill the tank as fast as the water will flow.

1 month ago

Why wouldn’t you move the fresh water into the gray tank? It seems that disconnecting the external water source, turning on the fresh water pump and then opening the spigots would do the trick. Is this possible?

1 month ago
Reply to  volnavy007

Sounds like a plan, leaves only a few gallons left in the tank to drain below. If they use city water all the time, they likely have the sewer hose already connected.

And I’ll put in my 2 cents as another full-timer. To me, it’s better to just use the fresh tank all the time. The water is always fresh. The water pressure for showers is always good. I’m always ready for a boondock night, or a campground with a shared spigot 200′ away. It’s quicker to roll on if I’m not rigged up with hoses.

And, in my system, by the time I have drawn down my fresh tank twice, it’s time to dump waste tanks. No guesswork.

1 month ago
Reply to  volnavy007

You don’t hook up fresh water systems to sewage tanks as that will contaminate your fresh water tank. And no, backflow fittings won’t work to prevent contamination that can lead to sickness or death.

1 month ago
Reply to  Crowman

Your fresh water tank IS already connected to the grey and the black tank. Just turn on the pump, open the faucets and flush the toilet.

Tom H
1 month ago

I’ve wondered about this for some time. I don’t like just flooding the ground under the rig when I dump the FW tank. Thanks for the tip!!

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