Installing a clean out at home

Smoothio wrote:
I’m having a slab and hookups put in my side yard for RV parking. The clean out will tap into the sewer system from my property in CA. I want to make sure the Contractor is doing it right, so asking for guidelines from the group around:
1). How far away should the clean out be from the rig (away from the rig and/or downstream)? This is my most important question
2). Is there a pipe thickness/material I should be requiring?
3). For the hose hookup, is there a kind/brand I need to mandate?
4). Tips to make sure it doesn’t stink (like threaded cap, any shapes/slope I need to look for, etc.)

I am in California and built a home a few years back and added a clean out for my RV and anyone coming for an extended visit.

1. I put mine just off the house because I wasn't sure just yet where the RV would end up being parked. However, now that I do know, I'd place it where ever would be the most convenient for connection to my RV. I have one of those powered macerators and the hose is 10' long I think. I'd place it where it would be out of the way when the RV is either home or away and is easy for a 10' hose to connect to.

2. When I spoke to my contractor plumber, I told him what I wanted to do; install an RV clean out connected to my existing sewer line. He said it's exactly what a simple clean-out is for any sewer line in any home. I have my master bath on that side of the house, so he just extended the line from the toilet out past the patio by about a foot and put a 90 elbow on to point it straight up and pitched it right for drain. NO TRAP. A cap is added but that's for another question. Same size and material for a home toilet. I think it's 4" ABS for code in my area. But PVC and cast iron are also legal. In any case, the inspector from the county didn't have any problem with it. I told him it's simply a clean out that may someday be used for RV black and gray tank flushes and he just nodded.

3. I assume you mean water hook up when you say 'hose' hookup. Any simple water bib will work fine. I installed one with a ballcock valve because it's a half turn full on/off instead of multi turn like your regular garden hose type. Be sure it's tied into your cold water line, not hot, and that the line has a vacuum break on it. Those are usually right where the main water line comes into the house and prevent water from back washing into your home's water lines. Sorta a one way valve. Every outside bib should have it's own, including sprinkler lines. If water is somehow shut off, residual water can't back flow into your home's drinking water supply. It is installed about 20' away from the clean out in exact opposite end of the RV so that the fresh water hose and the sewer hook ups do not come near each other and their hoses do not cross.

4. I installed a simple rubber cap that had been used by the contractor to leak test the drain. (A building code test that the inspector checks for) It uses a stainless steel hose clamp with a wide screw head on it like wings so I can turn it by hand to tighten and loosen. Threaded ABS or any plastic pipe are not meant for more than a few uses and will cause trouble later on down the road. I also placed a flush mount water meter box over the whole thing. You may have seen these used for hiding irrigation sprinkler manifolds as well. Mine looks sorta like this;

Note; I first dug out and poured concrete about twice the size as a base so nothing can burrow up into this space. Get two; one for your water hose and one for your sewer. Buy them big enough to stow the hose and the drain pipes used to connect to the RV. This is very convenient.
The finished height of these boxes are flush with the finished RV parking spot. It's better to dig too deep and pour a floor of concrete than to go too shallow and have the box stick above final grade. You can always add bricks or something to space it up or even pour more concrete for final effect. Add a drain if you get lots of rain. I don't but if I fill it with water while washing the RV, it only takes minutes for it to self-drain anyways.
Another nice feature of this is; if you happen to slop some black water around the clean out while disconnecting or it leaks because you didn't attach it right, the recessed box area will capture it and it won't go running all over your parking pad. Just hose it down and let it drain a few times to clean it up.