Black and Grey holding tank layout - best practice

[Seaboldarch]

Where do I start...I've started the remodel of my 73 Sovereign 31' rear bath. The previous owner had started a remodel on it, but I've torn it all out. I didn't understand the direction they were going with it, and I wasn't super happy with the quality of the workmanship. They also didn't appear to have a decent plan on the plumbing. This also means I don't understand how things were done originally or with what is there.

I am new to RV planning and design work which is causing some analysis paralysis finalizing a plan to get the tank(s) ordered. Black water tank is decent shape. There is no grey water tank. I am trying to figure out the best layout for adding a grey tank, and where to put the connections in the new tank. I've gone back and forth on having a blackwater tank or not. Today, I think I am going to keep it in the mix. Here is a pic of what I am working with.

Any advice, tips, pictures, link, etc on the best way to get this into a functional plumbing system. They also have torn up the endcap, which I assume means I should just take it all out. Is it repairable? I have seen so many posts on any of this, but all that I have found don't take too big of a deep dive into this stage of things. Thanks for any help or direction on where to look!

[dbj216]

Greetings Seaboldarch: Welcome to these Forums and the vintage Airstream hobby. You jumped right in the deep end with your 73 Sovereign 31. I enjoy the vintage Airstream hobby and spend last winter under a friend's 76 Sovereign. Maybe I can offer some of my experience with waste water tanks.

Airstream was big on rear baths way back when. They offered a big, luxury bath with tub and hanging closets that I'm sure sold a lot of trailers. But there is not a lot of room for two waste water tanks at the rear of the trailer. And Airstream drained the tanks out the rear of the trailer next to the bumper.

By the mid eighties the rear bath was waning and a mid bath layout was becoming more popular. Our 86 Limited 34' has a mid bath, with the bedroom at the rear of the trailer. I think it is a better floor layout as you don't have to walk through the bedroom to get to the bathroom. Sovereign trailers in the seventies had a mid bath option, see link below.

I installed a 30 gallon black tank, and a 27 gallon grey water tank under my 75 Overlander 27'. I kept the rear bath layout. I threw away the original tanks as they were shot, and too small. I drained the bath sink into the black tank to more evenly distribute the waste water. The shower drains forward into the new grey tank that I mounted behind the black tank. Two photos below show the tanks.

RV waste water tanks are readily available. But it is totally dependent on where your toilet is going, and how you will plumb the waste water drains. Modern convention is to drain the tanks out the street side of the trailer as that is the campground convention in most places.

David

https://www.airstream.com/wp-content...rplans-276.pdf