Can you hook an RV holding tank to a septic system at our house?

[synergycoach]

We are new to RVing.  We are considering purchasing an RV as a second home.  We are wondering if the holding tank can be hooked up to a septic system at home? 

[LindaH]

The answer is "yes," if you have a cleanout near where your RV is parked.  If the cleanout is far from the RV, you could use a macerator.

[synergycoach]

Thanks for the information.   What is a macerator and what does it do?  The learning curve is steep for now. 

[junglejim0745]

Hooking an RV septic into a home septic system is very easy. Remember sewer lines do not need any quick drops because the water will leave the solids if there are any. All elevation changes should be 90 degree drops to keep the two in the same area. One inch of drop in a one hundred foot line is almost overkill, we always tried for no more than a half inch drop per hundred foot, but that is hard to do using plastic line. Ideally the solids are kept with the liquid and casually float to the tank entrance.

Hook your RV dump line into the septic system between the house and septic tank, never into the drain field. Another option is to drop the septic discharge from you RV directly into the top of the septic tank, preferably before the baffle, but it will work if that is not possible. A macerator or other grinder will help but is not a requirement. I have installed RV dump lines into several septic systems, used both methods and never had a problem with them. First one I installed was in about the early 1970's and it is still being used to dump RV septic waste.

The reason I mentioned to install the dump line between the house and septic tank is that I had a dear friend that decided to put in his own septic dump for their RV and hooked it in AFTER the tank and before the leach lines. Needless to say it took us a while digging up the lines and replacing them to get his system working properly again. If the dump is being used daily or very frequently one needs to make sure to hook in between the house and tank, but for personal occasional use dumping into the tank after the baffle will work. The baffle in septic tanks is an insurance policy to ensure that the solids go down, not across the top of the liquid in the tank and out into the drain lines.

I installed septic systems for quite a few years and have seen some weird things people have done with their systems. Many times it was job security to have those people around.

Happy RVing. 

[Steven]

for personal occasional use dumping into the tank after the baffle will work. The baffle in septic tanks is an insurance policy to ensure that the solids go down, not across the top of the liquid in the tank and out into the drain lines.

Great info Jim.  Just to make sure I understand what you're saying:

It is always best to dump AHEAD of the baffle but for occasional use it is okay to dump AFTER  the baffle. Is that right?

What is the effect on the septic tank when dumping a 45 gallon black tank all at once?

Also, logic would suggest that using a macerator would be smart but practically speaking, how necessary is it?   

[junglejim0745]

for personal occasional use dumping into the tank after the baffle will work. The baffle in septic tanks is an insurance policy to ensure that the solids go down, not across the top of the liquid in the tank and out into the drain lines.

Great info Jim.  Just to make sure I understand what you're saying:

It is always best to dump AHEAD of the baffle but for occasional use it is okay to dump AFTER  the baffle. Is that right?

What is the effect on the septic tank when dumping a 45 gallon black tank all at once?


Also, logic would suggest that using a macerator would be smart but practically speaking, how necessary is it?  

You got it Steven, actually I have never seen a dump coming in after the baffle that had problems, because most solids will settle to the bottom anyway. If dumping in after the baffle it is a good idea to make sure the waste enters perpendicular, and even to drop the end of the dump down into the water a few inches. This helps direct the solids to the bottom. I always put the dump about six inches down into the water. NEVER bring waste in AFTER the baffle in a horizontal configuration as the agitation could send the solids across the top of the liquid right into the drain field outlet.

Dumping a forty five gallon tank all at once won't affect anything at all unless the pipe configuration is as mentioned above, horizontal to the liquid, then it might depend on how far the inlet pipe is from the drain field outlet. I have seen some really weird configurations in septic tanks, and amazingly most of them worked great.

When installing new systems where the lots were big enough for RV's to be parked on them I always offered to install an RV dump free of charge and connected it between the house and tank whenever possible. I figured it would save digging up the yard later to install one, and the additional cost of the pipe was minimal.

Happy RVing.  

[Sleepy Hollow]

We are new to RVing.  We are considering purchasing an RV as a second home.  We are wondering if the holding tank can be hooked up to a septic system at home?

I hope I'm not too late, do not use harsh chemicals in your RV and then dump into a septic system. The chemicals will destroy the bacteria inside the septic tank and basically render the septic system useless. It will clog and back-up and become VERY expensive to fix.

In addition, if you have a water-well on your property (as I do on both of my farms that I move our RV to and from) the chemicals will leach down into your aquafier and you'll be drinking formaldhyde. 

Make sure you use one of the several "green" holding tank treatments available. I use something called "Mean Green". Although it does nothing to make the toilet area smell better, it helps to break down solids in your holding tank and won't harm a septic system.   

[AChase]

Not sure if this reply is a bit too late...

Aside from making sure that you're not using any harsh chemicals in your RV's holding tank, make sure that you check the size of your septic system before you dump here. The sudden surge of sewage material may cause your septic system to get overworked and will cause you problems in the future.

[Stan Schultz]

... What is the effect on the septic tank when dumping a 45 gallon black tank all at once? ...

I will relate a story about an RVing friend of mine from several decades ago.

"Jim" and his family (wife + 2 teenagers) lived on a "hobby farm" with a septic tank/drain field. And, Jim had installed a clean-out handy to the spot where he parked his 5er. (Jim held a 9 to 5 job in the city.) They had been gone a week fishing. I'm not sure if they dumped while they were away, but I know that they hadn't dumped for several days before they returned home. I have a pretty strong feeling that the holding tanks were pretty full.

They pulled in late that Sunday night. The wife immediately carried several arm loads of dirty dishes into the kitchen and cranked up the automatic dishwasher. Then, she apparently started a laundry. In the meantime both teenagers took showers. And, while all this was going on Jim emptied his tanks into their septic system. And, as they went to bed, apparently both Jim and wife also took showers.

Do you see where I'm going with this?

When they got up the next morning they were greeted with a small lake of raw sewage in their yard. And, that's when they called one of junglejim0745's compadres to clean up the mess. They NEVER did that again!

Just food for thought.