Macerating/dumping into septic system vent stack.

I'd ask a plumber to put a proper clean-out by the RV. Most will understand the purpose of the "clean-out" and even put the proper screw threads in place so it can be used to empty out the RV's tanks.

We have a clean out right by the road that I put in when installing our sewer line. If I cant dump at the camp ground I can pull in the drive way and dump there, most septic tanks are way over sized so don't worry about over filling it.

In 100% agreement with "don't ask, don't tell". :)

magictom wrote:
We are brand new 5th wheel owners. We have a massive septic system with no easy access clean out, but there is a vent stack right next to our 5th wheel. Providing we are adding the recommended chemicals into our toilet is macerating waste & dumping into a vent stack safe for the septic system? Thanks for your help!

If it's situated right next to where you're parking your fifth wheel, I think it's more likely a cleanout than a "vent stack". A vent for the tank or drainfied would have to be directly above it/them, and presumably you're not parking atop either.

FYI:
Most legally installed septic systems require plans to be filed with the local Health Department or other permitting authority- a quick trip there to look at your file would answer any questions you may have as to exactly what that pipe is for. You needn't tell them of course why you're asking, though I doubt they'd care.

Word to the wise:
If it is listed as some sort of "vent", do look very thoroughly into how/where it enters the system. If it's only meant to move air/gases, it may be just above some sort of barrier that would preclude passage of some materials. There also may be screens present to exclude varmint entry.

A vent often connects to a commode or lavatory drain to vent their flow and pouring sewer down such a vent may actually cause the commode or lavatory to overflow.

PastorCharlie wrote:
A vent often connects to a commode or lavatory drain to vent their flow and pouring sewer down such a vent may actually cause the commode or lavatory to overflow.

all of that type of vent in my house vent out to the roof. can't really climb up there to use my stinky slinky.
bumpy

ChooChooMan74 wrote:
We have a brand new system. The vent on our system is in the leaching field. You don't want to start pumping solids into the leaching field.

Now I know the reason for the vent stack... And putting it in the leaching field would.. Well,,, it can not do it's job there... That is unless it is one of at least TWO vent stacks.. then it might work,,, But I doubt it.

The vent is there for two reasons.. One I'm sure you can figure out

The other is vacuum breaker,,, IN another time and place we are arguing if the Sewer Solution is a jet pump (It is). Imagine you flush your toilet... The swift rush of water will suck all the water out of the drain traps in the house... SO, they put in a vent, to admit air, and let the traps remain ... trapped.

korbe wrote:
As far as I know,a normal septic tank isn't vented. ...

Yes, a septic tank is vented, it vents up through the house stack and out the roof just like municipal connected systems. At least that's how they are supposed to be plumbed.

I would find it hard to believe the OP has true septic vent stack at ground level as this would be venting methane gas low to the ground. The chances of fire or explosion would be high as well as the constant smell of septic fumes.

The direct venting of septic tanks is very rare, but sometimes done.

If you are venting the inlet baffle side, you might be able to use this line. (I wouldn't, but you could be able to.)

If the vent is on the outlet baffle side, you are really risking sending solids into the drain field.

The thing you don't want to do is stir up floating scum and send it over to the outlet side. If you introduce sewage down into a vent line, you risk doing this. Sewage is supposed to enter the tank through the inlet pipe. This inlet is baffled to direct the flow down below the scum layer. If you look into a septic tank, it will have a thick layer of nasty floating scum. This is made up of grease and other floating stuff. You don't want that in your leach field. Clog that up and you are in for costly repairs.

The inlet baffle also directs flow down to help settle solids out. Scum floats and is trapped behind baffles. Solids sink and are trapped behind baffles. Mostly clear effluent passes through to leach field and is absorbed into soils. A good system will have an effluent filter prior to the leach field that gets cleaned out regularly.

You should instal a clean out between house and tanks and dump the RV there. A modest amount of RV sewage won't hurt a decent sized septic system if introduced properly.

Try to track down a set of plans for your system. Or, hire a pumper truck and try to see how your tank is baffled while he is pumping it down. You may be able to see how that vent line enters. A really good-been in business a long time septic hauler might even know your system, who installed it and how they preferred to set up baffles and vents. It the house isn't that old, you may be able to track down the company that installed it.

The best solution would be for a plumber to install a "clean-out" that connects to the baffled inlet pipe. That way, you know that you are dumping in the right place. While you are at it, maybe consider having the plumber add an anti-backflow device between the pipe and the house, so a septic tank backup backs up at the tank, and not into your house. Caveat: The backflow device will need maintained periodically or else it won't work when you need it the most.

Actually, the absolute best solution I have seen was a separate septic tank and two leach fields (with a large valve to swap between them yearly) just for the RV. However, that might be a bit of overkill.