Another newbie question

[Ranchhand]

When staying at a full hookup site with sewer is it ok to use the same water hydrant that everyone uses for there freshwater to flush your black tank. I understand that I should use a different hose than my freshwater hose. I’m assuming any tank rinse tool will have a check valve/back flow preventer. Tried searching for the answers but couldn’t find what I was looking for.

[jsmith948]

Yes.
Even though there is a vacuum breaker/check valve in the trailer's rinse system, for added insurance against contaminating the fresh water spigot, I put a plastic anti-siphon fitting on the spigot before attaching my rinse hose. Probably don't need to...but I do. It's just me:)

[whcarr]

Great question. I have never worried about the water running back when using the flush system. Always assumed that the water tank flush line was long enough so any back wash stayed there. I always have some water run back out when I remove my hose from the trailer fitting( a cup full). Can't believe it's a problem. But you got me thinking, gonna get me a one way or a shut off for the hose, that way I'll know!

[CWtheMan]

There is another reason to have two garden hoses. First there is the white one just about everyone uses for their fresh water. The other one should be anther color - ours is normally blue - for easy recognition and it's also used for to connect to the black tank flushing valve. The other reason for the 2nd hose is gray water. Sooner or later you're going to be in a CG that only allows gray water dumping on site. Gray water dumping is allowed in a lot of state parks. However, many CGs & RV Parks around the country have gray water only dumping and provide a dump/flush station for black water.

One of the largest CGs we have stayed at that had gray water sites was the Odetha Camping Resort, at Bazrah, CT

http://odetah.com/WEG.aspx

If you've seen a gray water connection cap and wondered about it, here is a picture. If you do a lot of traveling you should have one in your spare parts box.

http://www.keystoneforums.com/forums/picture.php?albumid=40&pictureid=6153

[German Shepherd Guy]

Hello. :cool: There have been some good threads on this lately, I think this season I will have a separate hose of a different color and put a back flow preventer



https://smile.amazon.com/gp/product/B000DZHA7S/ref=ox_sc_act_title_3?smid=A1YIGBIEGZK525&psc=1


on my flush inlet valve. If you have an older model that does not have a black flush fitting built in it could go on the end of the hose you use.



Looks like cheap insurance. Some Canadian members told a horror story of what can go wrong if e-coli is sucked back into the flesh water supply.

[Knights300ml]

Please pardon my ignorance as my trailer is first I've owned with black tank flush and i was under the impression that it was a completely separate inlet line than fresh water fill/city connection and only runs to black water tank so I do agree with separate hose I'm not grasping how it would back flow to fresh water tank?

[JRTJH]

Please pardon my ignorance as my trailer is first I've owned with black tank flush and i was under the impression that it was a completely separate inlet line than fresh water fill/city connection and only runs to black water tank so I do agree with separate hose I'm not grasping how it would back flow to fresh water tank?

The black tank flush system is not connected to the fresh water tank and that's not the question that's being discussed. The discussion centers around connecting to the faucet in the campground and whether, if the black tank flush system might backflow, whether it would get "poo water" as far up the hose as to contaminate the campground faucet. If you've ever been around some of the "older parks" with less than perfect plumbing, you've probably walked in mud to get to the dripping campground faucet to connect your hose so you can use the "city water feature"... Invariably, that faucet isn't in one of the white, lighthouse looking things, but is stuck up, out of the ground on the end of a half inch or 3/4 inch iron pipe, surrounded by a few rocks and lots of mud. Most of them, in that condition, won't turn off and I question whether connecting my hose to it might get mud into my trailer plumbing system.

Given that kind of "full hookup site" in an older campground, without an anti-siphon valve and/or a backflow device, the question is, "could" (not would) the "poo water" flow down the hose far enough to get "poo" on the threads of the muddy campground faucet..... The answer, if things failed to function, then yes, it could possibly backflow that far.... The next question, "if I'm using the same hose, then connect it to my city water inlet, (either here or at the next campground) am I going to have "poo water" that was left in my hose being pushed into my camper water supply? The answer to that, is, "If there's crap in your hose and you connect it to your city water inlet and turn on the campground faucet, you'll push "crap" into your trailer plumbing and the coffee likely will have a distinct aroma, probably not that of "freshly roasted beans".....

[66joej]

I always use one of these at the campsite faucet. One hose for fresh water and one for black tank rinse. Only turn on black tank rinse hose when flushing.